HARC TEK NET

 

Next HARC TEK NET will be…..

 

October 17, 2021

“Harc Repeater Network”

By WB6AMT

 

 

WELCOME all to the

Henderson Amateur Radio Club’s 

Sunday Night  TEK NET

 Subjects that have already been discussed will be displayed in GREEN text to show it has been discussed.

Sessions in ORANGE means that that session has been archived and you simply need to click on the ORANGE date/session to go directly to that Tek Net page.

The HARC Tek Net will be on all of the normally linked HARC repeaters and affiliates every Sunday evening at 8:00pm PST.

The photos, drawings and diagrams found here will assist with visually understanding the subject for that net discussion and can be downloaded by right click on any image and save it to your computer.

 

     Future subjects for discussion, which one will you do?

  • What do you think of the audio on most repeaters

  • What does it take to have a successful repeater

  • Ham swap meets, do you go

  • What does it take to have a successful repeater

  • Building your own antennas

  • Have you ever built or owned a repeater

  • Power supplies- operation and failures –  switching types

  • Homebrew projects “What project are you working on?”

  • Stealth or disquise antennas in an HOA

  • What does a swr meter really tell you

PAST TEK NETS

Click on any ORANGE archived Tek Net to go directly to that session’s page, I will get them all archived as soon as I can.

 Aug 11, 2019 – Power supplies- analog type- WB6AMT

 

October 17, 2021

“HARC Repeater Network”

By WB6AMT

Tonight’s topic was requested by one of our regular check-ins, his question was “why and how is our repeaters linked”?

The diagrams should clear some of the muddy waters and give a clear straigh forward understanding of what’s going on behind the scenes.

I will not be discussing anything other than ALLSTAR using Hamvoip, such as Echolink or IRLP…please no questions on those subjects we can cover tha at another time.

 

WHY LINK REPEATERS TOGETHER USING ALLSTAR?

          – To increase our coverage area

          – To add crossbanding to the network, exp. 10Mtrs, 6Mtrs, 2 Mtrs, UHF 440 & 900Mhz

          – To allow stations other than repeaters to connect to the network

          – To allow cross mode operation such as a DMR bridge

 

METHODS OF LINKING REPEATERS TOGETHER

            – Wireline or direct connection, can be at the same site or a different location

            – Using radios as the link connection

            – Internet Linking connection

 

#1 Direct or Wired connectionRptLink1

As you can see above there are only four signals needed to connect a repeater or radio to another repeater or radio.

These four signals are the only signals needed no matter what method you chose for your linking project.

An example would be a UHF repeater on a mountaintop site and later down the road you install a 6Mtr repeater in the same site, a four conductor wire with a ground or shield will do the job nicely.

You can also connect to a set of Telco wires provided by the local telephone company that may be available at the repeater site and also to a radio at your home QTH or another mountain radio site.

 

#2  Radio Linking

Rpt2

 

#3 Internet Linking using VoIP

RoIP or Radio over Internet Protocal is the process of sending and receiving radio transmissions the internat as the transmission medium.

We use Hamvoip software to communicate to the Allstarlink.org website.

Rpt3

 

#4  The HARC W7HEN HUB

rptHub

The purpose of the club using a separate HUb is so the the hub can focus on the connection handling demands without having the repeater controller aspects involved.

That is why it has been built to be robust for this reason.

The hub can manage the connections of many nodes (at times over 100+ connections) simulataneously with no difficulty.

At times during the Sunday night net  you may have heard 3 or more stations checking in and they could all be heard clearly…(on top of each other, lol)..

 

WHAT HAPPENS WHEN YOU TRY TO CONNECT TO A NODE.

 When a node gets a command to connect to another node, it doesn’t actually get routed thru Allstarlink.org even though communications has been established.

It queries Allstarlink.org to look up the destination node’s IP address and the port number that will allow inbound connections.

Allstarlink.org acts as a DNS or directory lookup service for all the currently registered nodes on Allstarlink.org. When you power up your node the IP address it reads back along with your call, the lookup just occurred.

Allstarlink.org returns the IP address and the port (usually 4569) of the remote node. Then the calling node will attempt to make a direct connection to the remote node using the IP address that Allstarlink.org just provided earlier.

Once the connection is made, Allstarlink.org is out of the picture and the communication goes direct between the two nodes via the internet until the connections is broken or disconnected.       

   

WHAT DO WE USE FOR EQUIPMENT?

         – The computer is a Raspberry Pi3 B+ in the repeater controllers at the repeater site.

         – Masters Communication USB Radio Interface board

         – The Raspberry Pi is loaded with the Hamvoip software that communicates with Allstarlink.org   

            for signal routing.

         – All the HARC repeater controllers are built in EMI die-cast aluminum RF shilelded enclosures.

 

WHY USE HAMVOIP SOFTWARE?

             – It’s free!  Hamvoip is the #1 Asterisk VoIP software that most Allstar repeaters use for

                linking.

             – Can be configured as a public or private connection system.

             – It’s been around since 1999.

             – It is currently being used in over 1,000,000 servers around the world in 180+ countries for 

                PBX business telephone systems.

             – Updating to a new current version is almost effortless.

 

WHAT ARE THE ADVANTAGES OF USING A RASPBERRY Pi ?

               – Raspberry Pi 3 family is a low cost investment, around $35.00

               – Pi has a small foorprint size in your chassis

              – Low power consumption

              – Runs off of battery backup easily

              – No moving parts!   The SD card contains the software and not a hard disk drive, prone to fail

                over time.

              – Remote configurable

              – Extremely reliable

              – Great customer support to the ham community

 

Just like the achilles heel has termendous strenth in your body there is a weakness that leads to failure…

That weakness affecting Allstar is… if the internet connection should go down or has any significant data paclet loss than Allstar audio can sound pretty bad and act kind of stupid.

Keep that in mind and realize that the system is optomized and when it has problems, normally its’s just temporary, so try to curve the griping about the system needing to be looked at, it really hasa been optimized.

When the internet problems ( usually Cox) clear, it normally comes back just like her old reliable self.

There are so many folks on this network that can answer any of your questions at any time, use them.

 

DE WB6AMT   

(Thank You Jim Dixon WB6NIL for all your hard work, the unofficial Father of Allstar, unxepectadly became a SK in December 2016)

 

 

 

 

______________________________________________________________________________________________________

October 10, 2021

” Desoldering tools”

By ALAN GIFFORD AI7HZ

Ohiogo, Mehow, Hola, Hello Tech net attendee’s.

AI7HZ ALAN here to talk about de-soldering tool and methods. In Casino Gaming I learned a few things along the way and wish to share my observations.

First, The way to tell the difference between a Casino Employee and a Customer when in the Restroom, The Casino employee washes His or her hands before using the facilities. Think about that.

Wash your hands frequently!

Second, Having the right tools for the task required, makes your work look professional. Not like a expert.

PICTURE #1 Soldering and de-soldering on Circuit boards require lots of tools to complete repairs. Not only in choosing the appropriate solder type but also the method of removing or stuffing the components on the Board. The CHEM Wik shown here is a copper braid flux wick which is used with a soldering iron to draw or pull the solder off components. This method sometimes heats the circuit board to hot and damages the board and or lifts pads. I used the chem-wik mostly to level the excess solder on pads of the circuit board. Also displayed is a Soldering tip cleaner, this consists of coiled brass wire in a container. I prefer not to use wet or dry sponges to clean by solder nozzles or Tips. 1 (1)

 

PICTURE #2 The bulb sucker, A cheap method of sucking up solder. Can be frustrating to use and I guess I should read the 12 page manual came with this product. Maybe I need to change the batteries on it. It definitely better at sucking up tiny gold flakes in a gold pan. pix2

 

PICTURE #3 In lite blue we have a manual plastic de-soldering sucker and a OK industries heated tip de-soldering sucker. The blue de-soldering plunger requires no power and works relative good but inconsistent.  The white plastic tips are normally deformed because of being held too close to a hot iron trying to lift the solder. Both units work in the same manner. The plunger must be compressed and on the side a push button is used to release and create the suction. 3 (1)

 

PICTURE #4 and 5  This shows the de-solder assemblies pulled apart and the spring loaded mechanism internals. Both units need to be cleaned after 10 to 15 times of use. You must remove and discard the trapped solder from inside and on the faceplate.  Silicon grease or Vaseline is used to seal the rubber ring inside the tube to create suction and lubrication. The OK industry  heated element de-soldering iron  was a step in the right direction. This does not require the use of a soldering iron because of the heated tip and can be operated with one hand. From what I can tell the suction draw was not as strong.  I really don’t know because I have never used it. It was a Nice tool at the time of purchase. pix45 (1)

 

PICTURE #6 Now we’re seeing The HAKKO 808 standalone de-soldering unit. This also came in a complete re-work ESD station which includes a Micro and Standard iron, A Hot air gun, A 808 de-soldering gun plus a hot plate.  This unit had a diaphragm plunger assemble pump in the rear of the gun.  It shows a rotary dial pot which adjusted the temperature starting at 600 degrees and incrementing by 50 degrees. The heating element and the temperature sensors are in the tip, rather than in the barrel as in other irons; this allows the system to accurately maintain the preset temperature. Pull the red trigger and suck the solder up. One drawback of 808 is once you plug to power it hot. There was no on and off switch to power up. 6 (1)

 

PICTURE #7  This 808 was purchased in 1994.  My personal used for home projects and repairs. We see here the Glass case removed, which traps the solder being sucked up the ceramic heated tube. The metal sleeve which also holds the nozzles tip in place to melt the solder. Again, like the previous units pictured unit, Silicon grease or Vaseline in used to seal the glass case to create vacuum to suck the solder in. A Small drill and or a metal pin is used to clean the inner tube of solder debris.  Hakko has different size Tips available for applications and can still be purchased for both the 808 and FR300. 7 (1)

 

PICTURE #8 This shows another angle of the 808 with the cotton paper filter showing. Most individuals replace this filter with fine steal wool inside the case tube for easier cleaning and a better draw of solder thru the shaft tube assembly. Amazingly , Hakko parts for repairs can still be purchased for this discontinued items since 2004.  pix8 QUESTIONS?

 

Video 

Hakko-808 desoldering tool unboxing, review, demo – YouTube

 

PICTURE #9 Now we see the Hakko 808 compared to the Hakko FR300. Obviously smaller, lighter, smaller pump assembly inside and lower on the gun. The FR300 has a on and off switch on the rear of the handle. It has a smaller easier to clean and remove glass tube. Did I mention it’s blue and yellow?   Has a red LED on the front of handle to indicate on or off status. The Hakko cost me $200 in 2011.  You can still get them on eBay but they were discontinued in 2017.  The new model is the FR301 series. 9 (1)

 

PICTURE #10  shows this Fr300 the Cotton paper filter and the metal case which hold the nozzle tip in place  off. The Metal case is removed by a black socket which is easier to remove then the 808 version. This shaft is slotted and rotates clockwise for 45 degree easy removal. Both the 808 and Fr300 use the same plunger and drill assembly to clean solder debris from the inner tube. The glass tube is shorter and has notches on the sides. The cotton and metal pre-filter are the same on these units.  Again, Fine steel wool is also used instead of cotton filters. Placing the bundle before the metal filter allows the unit to inhale better for a stronger draw of solder. The Nozzle tip and shafts are not interchangeable between these units. Hakko tips and parts can still be purchased for both units. 10 (1)

 

PICTURE #11  Showing the left side of the FR300. We see the yellow push button which is used to remove and to lock the glass case to be clean.  The markings also show temperature setting and on and off indicator. The temperature settings start at 600 and increase to 910 degrees F.   Both units can be used all day and depending on what being de-soldered. Simply dumping the contents of the Glass tube is all that required if needed. I cleaned my Hakko de-soldering station at the end of the day, always. I sure the FR300 is improvement over the 808 but I favor my 808. It’s can’t do the work of a hot air gun or a hot plate, but it’s the most useful tool I use for de-soldering.11 (1)

Yes, I’m sure that there are other manufactures making something similar to this type of device.

I worked for Sigma Games in the 80’s and they introduce me to Hakko products before they were sold in the US.  

Thank you for your time AI7HZ

_________________________________________________________________________________________________________________

October 3,2021

“A refresher on how to solder…and how not to solder a connection”

This will include thru-hole joints, SMD – Surface Mounted Devices, wire splices, repairing damaged traces or pads.

I have found that there are many opinions about soldering as there are folks soldering. The following has proven to work for my style of board assembly over the years.

While working at Southcom International in San Diego in the 1980’s, a company manufacturing military radio equipment under the parent company RF Harris, my job was the Manager of the Production Test Dept.

I oversaw the testing, alignment and repair of circuit boards being made on the assembly line including making ECN (Engineering Change Notices).

It was also my responsibility to teach an ISO 9000 (at the time)  Soldering training course to the assembly line workers doing the assemblying of circuit boards going into a military radio like SC-106 HF Vehicle Communications unit and the SC-130 HF manpack radio for the United States Marine Corps and United States Army.

There are many requirements in that type of production soldering, including the correct amount of solder (and NO MORE) due to accumulated weight restrictions, when producing a military radio several thousand solder joints within a single radio with just a little too much solder and there is a very real weight difference in the overall unit’s weight, which can lead to board or unit rejection by Quality Assurance dept or the customer strict specifications.

Imagine this condition on satellite’s circuit boards assembly and the weight  specifications needed. It’s not unheard of to have 8,000 solder connections on the electronics inside the space capsule, not wanting to use too much solder can become a real weight factor.

I’m going to touch on what is practical and how to solder for ham building or repairing a circuit board today and the tools needed.

-Soldering station with Temperature control (Preferred) and tip assortment

soldering stations

-Dampened sponge to wipe the tip for each connection (called wetting)

-Quality solder (not lead-free) fluxed SN60/40 or similar, applies to Electronic Silver solder also. (See photo #5 below)

-Tip cleaner (helps to protect the tips plating tip cleaner

-Desoldering vacuum device or Desoldering Wick braid.

desoldering2desolder1

solder wick

 

Probably the single most important part of soldering is PRACTICE, PRACTICE, PRACTICE.

Make use of the following tips and tricks. Practice pc boards (new) are available for cost of postage. (email me)

I personally recommend a low wattage iron 15-40 watt or a soldering station with a temperature control.

This temperature control and proper soldering iron tip becomes very important depending on what your joint will be comprised of.

 

#1  Correct means to transfer heat to pad and component leadSolder image

 

#1A Soldering plated thru-holesBoard_design2

                     Notice the amount of solder used here.

 

#1B Lead sizesSoldering A

 

#2 Soldering TipsTips

 

#3   Soldering larger gauge wire (16-10 ga) to a terminal post or lug

IMG_20201129_234941756

Using a large conical tip 700 degrees, .030″ solder allows the heat to transfer quickly to all the wires and to the post to accept solder quickly without damaging the insulation on the wire by holding the tip on the connection longer than needed.

It’s necessary to use the correct size solder for the joint your making because of the amount of rosin core flux that will be released as the solder liquifies for the particular joint.  ( Here I used  63/37 .030″ ).

Too little flux and you will end up holding the tip on the connection too long to get the solder to flow & fill the joint and will burn the insulation and possibly the connection point.

I normally use .015″ solder for most of my circuit boards I build. This provides the correct amount of solder on these 1/8th watt resistors leads, integrated circuit pins, 3mm led leads etc.

The reason for .015″ is that all my boards are thru-hole plated and I want the entire thru-hole filled but without too much solder being used.

I want very little solder above the pcb surface so that the component leads can be flush cut to the pc board when finished. This prevents “a solder glob” to form.

 

#4  Leads cut close & flush with boardIMG_20210326_122111378

Initial trim to get out of the way of other solder joints, then a final flush cut of all joints.

 

#5 .015″ SolderIMG_20210326_133947063

Most of the solder we use on electronic circuits is labeled 60/40, meaning that it has 60% Tin by weight and 40% Lead by weight. 60/40 Sn-Pb, melts at 188 °C (370 °F)

Soldered labeled as 63/37  has slightly different weights and has a lower melting point, typically 183 degree C (361F).

.015″ solder is ok to use by hand on SMD solder connections without leaving too much solder on the connection pad or island.

The preferred method to solder Surface Mounted Devices is to use soldering paste on a cut-out stencil to apply the paste to the pads and a adjustable temperature hot-air soldering tool depending on the components being soldered.

 

#5A Hand applied pasteCU_Hand_Pasted_PCB

 

#5B Hand placement (stencil used )maxresdefault

 

#6 Tips and Hot-air noozles

71T07hSSOoL._AC_SL1500_

 

#6A Surface Mount Device soldering by hand prepping

SMD3

 

#6B Surface Mount Device soldering by handsmd4

By applying a small amount of solder to one of the pads first, then hold the part in place and re-wet (re-flow ) the connection with your needle tip to reflow the solder.

If all the pins are aligned correctly, make the next solder connection at the opposite end of the part to hold it in place and straight, while you solder the rest of the pins/pads.

Note- I used about a 1/16″ of .015″ solder for each pin/pad of the SMD Relay.

 

#7 SMD Parts2N2222 SMD

 

#8 Placing part by hand2N2222 SMD

At this time I need to say that it is possible to solder SMD parts by hand on a board like the above.

Is it easy? Not really!   Is it for the faint of heart…probably not.

While trying to do this demo, once the solder was on the pad I tried to place the transistor on the board with my SMD tweezer.….

The first attempt.…the transistor completely disappeared by the the time I moved from the bench top to the location highlighted by the Red arrow above. I never felt it leave the tweezers! Have no idea where it went!

The second attempt….the transistor made it to the board surface….but I breathed a sigh of relief and whoosh, it disappeared!

My final attempt (third transistor) was done with the help of a piece of scotch tape….. to grab the transistor on the mat with the tape, placed it on the board and stuck the tape to the board and soldered it in place to the first pad making sure it was straight. Easey-Peasey!

 

#9 Finally!2n2222

After discovering the tape trick, it was no problem getting the rest of the 1206 sized parts installed and soldered by hand.

 

#10 In-line wire splicesIMG_20210326_162008233

 

#10B  Just enough solder to fill the wiresIMG_20210326_162055542

                                All ready for a small piece of shrink tubing.

 

Problem Joints

Correcting a bad solder joint or fixing a missing pad or trace is not that hard to do with a little patience and analyzing how to go about the repair.

 

#11 Burn’t trace on a pc boardTrace

 

#11A  Trace jumpertrace fix

This is an excellent use of those resistor and component leads that get trimmed from your circuit board building projects. Be sure to pre-tin the wire lead with fresh solder prior to attaching to the connection.

I keep a 35mm film canistor filled with cut-off leads over the years, they make good jumpers, the bigger wires like 1/2 watt & 1watt resistor leads can handle considerable more current.  Don’t forget to clean the board of all the burn’t flux as it is corrosive if left on the board.

 

Repairing a missing pad

#12 Missing Pads

IMG_20210328_145815104

Missing pads normally occur when de-soldering single sided circuit board traces that are not thru-hole plated.

The pads or “Donut holes” lift off the board when heat is applied too long on a joint trying to unsolder a connection, and the adhesive bonding between the copper and the circuit material  is compromised.

The repair of a missing donut hole is similar to the burn’t trace repair.

Cleaning a short distance on to clean copper where the pad or trace lifted from, tin the copper with a little solder, and apply/ solder the new jumper lead.

 

#13 Missing Donut hole fix

images1

Next take a component lead cut-off and form it around the lead coming up thru the hole that is missing the pad, solder in place.

Next bend the lead to match the original trace layout over to the fresh copper you have pre-tinned, trim and solder in place. Make sure that the size of the replacement conductor is adequately sized for the current that the original pad/trace was handling.

 

#13A Point to point trace replacementf4vew03jm0v7j4x-large-e1537929441900

 

Another Donut hole repair, is to place a piece of copper foil and solder to the component lead and to the fresh copper on the trace itself.

 

#14 Alternmate Donut hole fix (occupies a lot of space)

images

I’m not a big fan of this type of repair because it normally is too close to surrounding component connections.

This a good way to repair a high current trace that has been damaged in a power supply, where a higher current carrying foil trace was damaged by a short circuit.

If you have any questions about a particular type of soldering issue, please send me a message at wb6amt@cox.net.

I have a supply of new PC boards to be used as practice boards. Come by my QTH or send postage and I will mail them to you, at the cost of postage.

REMEMBER…the smaller the trace or solder connection the less time and temperature is needed to solder or desolder the joint.

73 DE WB6AMT

 

_____________________________________________________________________________________________________________________

September 26, 2021

“Assembling the PL-259 RF connector”

By Tony WB6MIE

http://www.facebook.com/HARC-Technical-net-chat-104477997564655/photos/pcb.577473560265094/577470816932035/

 

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September 19, 2021

“Ask the pros night or often called, Stump the Chumps time”

 

 Before we get into the nights questions, I would like to pass on a bit info I received this week that looks pretty promising to those into wireless charging of their mobile devices.

Motorola recently demonstrated their power beam technology recently which is different then the current Qi technology.

Attempting to do with device charging, that Wifi did to internet, getting rid of the (Cat5) cables.

Instead of setting your device into a cradle or on a pad to charge, Motorola’s recent entry into the long range wireless charging landscape, happens when you are within range of about 3 meters or 10 feet.

Here  is a 30 second demo video 

Why the interest in long range charging?

The idea of charging your cell as soon as you enter the room is definately intriquing.

There are other devices that could benefit from this technology, like hearing aids, heart monitors, Diabetes monitors, smart door bells, digital door locks, security IP cameras and just about anything using a battery.

Motorola’s Gen 1 system ( distance 1 meter) was shown at Consumer Electronics Show back in January of this year.

This month gave us Gen 2 capable of a distance of over 3 meters about 10 ft with the capabilities to charge up to four devices at the same time.

Phones can now be charged at up to 3 meters (10 ft) of clear air between them and the charger. It’s one hefty charger equipped with a phased array with with a whopping 1,600 antennas.

The charger covers an arc of over 100º, so it can beam power to phones even if they are off to the side.

The charger can even handle some obstructions between it and the phone.

This means that the phone can be charged while it’s in your hand or your pocket. The charger can detect your body and aim the beam away from it so that it hits just the phone.

All this sounds very cool, but the draw back at this time is that it will be a bit on the slow side timewise to charge but that will most likely be the next thing that Motorola will work on.

Your thoughts and questions.

 

___________________________________________________________________________________________________________________

September 12, 2021

“Building a UHF ground plane antenna on the cheap

“on the cheap” doesn’t have to mean it’s not going to be an effective antenna by any means.

A UHF GP antenna can be as tall as 6″ and about 14″ across at the radials, the important thing is to get the antenna outside of the house.

 

Building a simple ground plane antenna for ham radio use.

By Tony Dinkel WB6MIE

#1teknet9-12-21019

 

For HARC TEK NET 9-12-202

 

In speaking to a lot of new hams on the HARC repeater network I have noticed that a lot of you are using hand-held radios with either the supplied antennas or some larger after market antennas. In addition to that, most of you are trying to use your radios inside your homes or inside your cars.

As some of you have found out, this is a way less than optimal method to get your signal to the repeater.

Where you are sitting inside your home and how you hold your radio has a lot to do with the strength with which you reach the repeater receiver. The repeater experts in the club do all we can do to make the repeaters as sensitive and as selective as possible.

As a new ham, you should be aware of ways to make it easier to radiate as much signal as possible outside your home, whether you are in an area that prohibits antennas or not.

I think you should build your first antenna.

It’s easy, fun and instructive. I did this one in less than an hour, including rummaging around in my junk boxes in garage for the parts I needed.

I started by building a spreadsheet for calculating wavelength in free space.

 

#2wavelength

 

I picked a frequency of 445.0 mhz because it is exactly the center of the UHF band segment that we use, 440 to 450 mhz.

Dividing the frequency in megahertz into the speed of light, the approximate speed at which radio waves travel in a vacuum, gives us the wavelength in meters.

By adjusting the numbers a little bit, we can get an answer in centimeters, smaller units are much easier to work with at these frequencies. As you can see from the spreadsheet, I got a result of about 67.5 cm. Dividing that by 4 gives us a quarter wavelength of 16.8 cm or about 6.5 inches.

So I went out to my garage to find some wire to build this antenna. I quickly spotted my spool of #14 bare copper that I use for building HF dipoles and radials for my HF vertical.

You can use anything. The first ground plane that I built in the 1960s was made out of wire coat hangers from my mom’s closet. While I was in the garage, I also found a type N, flange mount connector to use as the focal point for the antenna.

 

#3

teknet9-12-21003

This connector is old, but as connectors go, older is better.

 

#4

teknet9-12-21004

#5teknet9-12-21005

At first glance it appears to be dirty and tarnished. Don’t worry, it’s silver plated and the dirt is silver oxide. Silver oxide is still a great conductor of electricity.

 

#6

teknet9-12-21006

A thing you want to check when you are using a connector of dubious origin is the condition and alignment of the center pin. There is a slight misalignment of the pins in this picture, but it will be just fine for our project today.

I rounded up the 6.5 inch measurement and cut 5, 7 inch pieces of #14 wire. Extra wire is good because you want to start out long for a lower resonant frequency, that way you can trim down to your desired point of resonance.

 

#7teknet9-12-21001

 

#8teknet9-12-21002

Now I am ready to start assembly of the ground plane portion of the antenna.

 

#9teknet9-12-21009

 

#9teknet9-12-21008 - Copy

I put a small bend in 4 of the wires to allow them to slip into the four mounting holes of the flange connector. I also tinned both the holes on the connector and the ends of the wire that will contact the connector. This makes assembly much easier with two hands

 

#10teknet9-12-21010

The radials should “radiate” out in the direction that the apex of the flange angles point. This makes a ground plane with a conductor every 90°.

 

#11teknet9-12-21011

The bent ends of the radial wires may protrude through the flange slightly. You may want to use a pair of dikes to trim these off flush. I have gouged my knuckles on these sharp edges a few times in the past. The voice of experience!

 

#12teknet9-12-21012

 

After you have the ground plane assembled to your satisfaction, bend the radials downward at a 45° angle. This will make the antenna sit on your desk to make it easy to add the radiator and trim it in to resonance.

 

#13teknet9-12-21013 (1)

Now drop the 5th wire into the center conductor of the type N connector and see where it lands on the antenna analyzer.

 

#14teknet9-12-21014 (1)

Not too bad for the first shot. Slightly over 2:1 on our target frequency of 445.000Mhz.

 

#15teknet9-12-21015 (1)

I widened out the trace on the analyzer to see where the resonance point was, turns out it was at about 390 mhz, way out of the ham band. So I started trimming off the excess in about 1/8 inch increments, until I got to this…

 

#16teknet9-12-21017

I overshot the center mark by just a little bit. For purposes of this demonstration it is just fine. I’m not going to complain about a 1.159:1 match.

 

#17teknet9-12-21018

If your prefer your results in tabular form, you can see that the antenna is very close to 50 ohms impedance with very little reactive component, almost perfectly resistive. It has a VSWR of 1.045:1 which corresponds to a return loss of -33db.

 

#18teknet9-12-21019

 

Not bad for a 20 minute build!

 

Questions?

 

 

Quarter_Wave_Drawing

 

Here is a 1/4 wave ground plane antenna calculator: m0ukd.com/calculators/quarter-wave-ground-plane-antenna-calculator/

Don’t forget to seal the coax and connector with a coax seal tape.

 

By attaching a short piece of pvc pipe to the edge of the roof, you can drop the feed line down the pvc and the antenna can sit on top or if you decide to seal the top with an RTV sealant that will keep water out of your connector/ coax.

Your results will be amazing by getting that RF energy out into free space, instead of trying to penetrate the walls of your house will help dramatically to get the signal headed to the repeater.

By WB6MIE Tony

_____________________________________________________________________________________________________________________

September 5, 2021

“KJ7OEN 3-Band Vertical Antenna build”

 

3-Band Vertical Antenna build and Hiding from the HOA

I decided to build an HF vertical, 3 bands, 20, 10 and 6. The idea behind the build was to utilize what the QTH had to offer and hide the antenna.

Additionally, I wanted to do it without special fabrication at the race shop.

Everything utilized in the build was lying around or available at Home Depot/ Lowes.

 

#1 Pictures around the QTH

1

 

#2 2

 

#3 More QTH

3

 

#4 The stealth vertical support

4

                                          What would be best?

Dipole, Loop, Vertical, End Fed Wire?

The Vertical build uses a 4″x4″ weather proof box as the enclosure.

The SO239 connector was place in the middle of the box.

The driven elements were connected via a 3/824 bolt. I did this in case I ever wanted to try a ham stick, whip, etc.

 

#5 Driven element mounts

5

 

#6 Ground ring connections

6

 

#7   3/8″ x 24 mounting bolts

7

From there, I built telescopic tubes and soldered in a 3/824 jam nut.

The wire elements will be ¼ wave wire attached to the top of the tube.

The top of the wires will be attached via paracord and shock cord.

Once hoisted up, the tubes can be adjusted for resonance.

 

#8   Driven element connectors

8

 

#9 Mounting nuts in adjustable connectors

9

 

#10

10

 

#11  Ground radials for each band

11

¼ wave ground radials were built and laid out. 8 radials were made for each band.

A cradle was built out of Lexan, folded at 90 degrees to get the wires away from the trees.
Tennis balls were anchored at the bottom to hold snug against the tree and prevent twisting.

 

#12 Stealth mode placement

12

 

#13  Radiating elements

13

 

#14  1.06 on 20 meters!

14

 

#15

15

20 meters came out 1:1.06 across the band. 10 and 6 meters were under 1.5 swr. The best part is the HOA can’t see it.

Maybe if a golfer looks hard he could see it from the Golf Course. (Last PIC)

 

#16

16

 

#17

17

 

#18

18

 

#19  Virtually invisible from the golf course.

19

 

#20  Comfortable operating post, ready for action.

20

 

Thank you John for an excellent job on getting on the air on HF with what you have available.

John is on the HARC repeaters, if you have any additional questions that weren’t answered here give him a call.

 

I want to invite anyone else that has built a project that we could share with our Tek Net family of participants.

Get me your photos and the text to go with it and I will get it posted to the webpage for you.

 

____________________________________________________________________________________________________________

August 29,2021

 Why should I turn my radio on other than for club nets?

  • (Open forum type discussion)

#1  Why did you get a ham license and when?

 

#2  What steps did you have to take to get your license?

 

#3  How many years have you had your license and have  you operated the entire time.

 

#4  What do you find enjoyable about your “ON THE AIR” time?

 

#5   Do you think getting your ham license has made you more receptive to learning new technologies?

Without a doubt, ham radio for some was a gateway to newer technologies and aspects of ham radio.

 

#6   Any suggestions on how “NETS” are run?

 

#7   Do you think having two or more nets a week, Mid-Daytime & Nighttime would serve more club members? What kind?

 

#8   How many Nets do you regularly participate in?

 

#9   What type of Net would you like to see formed?

 

#10   How about interest in an organized 10 mtr Net or Roundtable schedule (so Technicians can participate).

How about an HF net?

 

———————————————————–

August 22,2021

“Can an external antenna on my car make that much difference?”

 

#1 The DB…

The first thing to understand is how does this db thing come into play with antennas.

When we talk about a db rating, what is really being expressed?

The dB is an abbreviation for decibel. One decibel is one tenth of a Bel, named for Alexander Graham Bell. The measurement quoted in dB describes the ratio (10 log power difference, 20 log voltage difference, etc.) between the quantity of two levels, the level being measured and a reference.

From a loss standpoint, if a measurement is deemed to be -3db between two levels, then that indicates a measurement of 1/2 or 50% lower signal level.

Example …. you have 100 ft of RG8X feedline from your base station radio to the antenna outside. The loss is approximately 8.6 db loss. (From chart below)

Your base radio is producing 50watts out into the coax to the antenna.

The actual RF energy that will be reaching the antenna will be approximately 9-10 watts of RF energy.

You have lost almost 40 watts of your original signal to feedline loss.

*NOTE- All feedlines have a degree of loss, be aware of this when you plan your antenna installation.

 

               
               
               
               
               
               
               
               
               

(You will see this described when looking at antenna feedline losses at a certain frequency limit on lengths of 100 ft or more). The below chart is from wire manufacturer Belden.

  10 MHz 30 Mhz 50 Mhz 100 Mhz 150 MHz 220 MHz 450 MHz
RG-174 3.3 5.5 6.6 8.9 13 17.3 25
RG-58 1.4 2.5 3.1 4.9 6.2 7.4 10.6
RG-8X 1.0 2.0 2.5 3.6 4.7 6.0 8.6
RG-8U 0.6 1.2 1.6 2.2 2.8 3.5 5.2
Belden 9913 0.4 0.8 1.1 1.3 1.7 2.1 3.1
Belden 9914 0.4 0.8 1.1 1.4 1.7 2.1 3.1
LMR-400 0.4 0.8 0.9 1.2 1.5 1.8 2.7
1/2″ Superflex 0.3 .56 0.73 1.04 1.3 1.6 2.3

A measurement level of +6db would indicate a signal level approximately 4 times the originating signal level on the reference antenna.

 

NOTE to mobile HT users – It has stated that the energy level losses from an HT inside of a vehicle is at times -11.3db or greater than the same signal level radiating from a center mounted 1/4  wave whip in the center of the vehicle’s roof.

That means that a 5 watt HT will be radiating a signal inside of a vehicle will be approximately equal to  .3125 watts actually radiating out of the vehicle.

 

#2 Some RF db examples…Loss visualization.

 

#3 Where to put the antenna? (reprinted from Motorola installation document)

aNTENNA_pLACEMENT

Also please keep in mind that anything not in the center of the roof now has to to be considered a directional antenna.

 

#4 Propagation between a 1/4 wave (spike) and 5/8 wave gain antennaGain_plot_70cm_vehicle

The closer you are to the repeater ( in the Las Vegas Valley) the higher angle of radiation from a spike antenna is going to be and serve you better than a gain antenna.

However at a distance farther from the repeater, the gain from the lower angle of radiation of the above antenna will most likely produce more signal at the repeater’s receiver if you are a greater distance from the repeater site.

 

 

6 Feedline losses

240-abr

 

 

#7 Antenna Types

page63

 

 

#7A

oshinvoy-uv-dual-band-mobile-radio-brackets-whip-antenna-145-435m-dual-band-car-two-way-radio-whip-antenna

 

 

#8 Questionable Mag mount from China

UT108UV-dual-band-antenna-with-SMA-plug.jpg_350x350

 

 

#9 Drilling a hole in my car will reduce the value.

As the manager of a Motorola Mobile Telephone Service shop in San Diego, Ca. years ago, I was asked that question very often by customers having mobile telephone antennas installed on their new vehicles.

I have questioned car dealerships, if a vehicle had a mobile telephone antenna (it was easier for them to understand why there was antenna on the vehicle) installed, would that affect the vehicle’s resale value when it was removed and a proper rubber flat antenna plug used to cover the hole.

My answer from the Mercedes, Jaguar, Rolls Royce, BMW, Chevrolet and Ford dealerships in San Diego, Ca. at the time all responded with no if the hole was plugged properly.

So….is it worth the trouble to install an antenna properly…absolutely.

Will it cost me money down the road….absolutely not (if removed and plugged properly).

Will it make a difference in performance of my radio transmissions, again… absolutely!

Antenna mounting holes can be as small as 3/8″ to 3/4″, all have plugs available.

CONCLUSION – Put a charge on that cordless drill and get ready to make your mobile radio talk and receive better than it ever has.

Most new antennas that you buy, will come with complete step-by-step instructions, including a tools needed list.

There are many hams here in the valley that will be glad to assist with the installation of a mobile antenna on your vehicle.

Also commercial two-way shops can do this work for you quickly and economically.

________________________________________________________________________________________________________________

August 15, 2021

“Ask The Pros” night, Also a discussion on operating Allstar nodes

There has been more and more Allstar node activity on the networks lately, suggesting that we need to address some of the operating practices directly related to connecting to and using the HARC Allstar hub.

The basic components of a node.

#1

Allstar_Block

 

#2

20190817_181727_Film3[1]

 

#3

Some of the new Clear Nodes heard on the network are popular and sound great.

Clear node

 

Current price is shown as #295.00

As can be seen, the node has a SA818 radio module allowing you to program on any VHF or UHF amateur frequency.

Product Details

ClearNode is a Raspberry Pi based AllStar, EchoLink and Digital Modes (DMR, P25, YSF, FCS, NXDN) simplex node with an integrated low power FM radio transceiver.

You can use your analog FM HT to work AllStar, EchoLink and the Digital modes.

The capabilities that have been added to this Rasp Pi node is not going to be talked about tonight, and can be found at the ClearNode website.

What is going to be discussed is how you should as a responsible user of the node, be familiar with how to operate on the different modes properly before setting up a clear node with no knowledge of what needs to be done before hand.

#4

The HARC ALLSTAR HUBHub

You can see that earlier today there were 12 different Allstar and Echolink nodes. Some of these nodes aren’t in the Las Vegas area which gives us a relatively wide area network when talking on any of the network repeaters like H1, H2, H5, and C1 in California.

The above bubble chart is showing that we have several personal nodes connected to the network at this time. When you come up and transmit on your node these are the minimum of stations that will broadcast your signal out to a great many more stations monitoring the frequencies.

I recommend that you should set your new Clear node up using the “Parrot” nodes to check how you will sound before actually connecting to the hub or anyone else’s node.

Just as it is important to properly modulate your transmitter by talking directly in the hole on your microphopne or the front of the HT, this will fully deviate the FM transmit signal and keep your audio level consistant on your node too.

This needs to be done when talking into your node’s radio.

By not keeping the same distance from your mouth to the microphone ( no more than 1/2″) creates a condition of up & down transmit level. Folks who are use to not talking right into the microphone, either because of old CB habits with amplified microphones talking at arms length or a condition called “Arm Chair Conversations” makes your transmit audio sound not nearly as good as it could sound or because your moving around while talking to the microphone.

While operating mobile I’m sure you have herard the up-down audio and how much of a pain it was to have to raise the radio volume and then the next guy talks and blasts you at an extreme volume.

I notice this a lot, having hearing issues because it seems to make understanding the spoken word very difficult at times.

There are few things that is a MAJOR no-no on the HARC network and needs to be adhered to at all times.

  • Do not connected to the Harc hub while you are not the active control operator ( unattended ).

  • When connecting to the HARC Hub always connect to the hub #44045 and NOT to the repeaters directly.

  • Do not connect to other nodes while still connected to the Harc Hub and then leave them connected.

  • When using the Parrot node or mode make sure that you disconnect when done, don’t leave connected.

  • Do not connect to the WINSYS node while connected to the Harc Hub.

When controlling your node be sure of the keypad sequence that you want to send, don’t allow to long of a space between digits or your sequence will be broken up and it wont work.

There is a plethora of different nodes all around the world for you to connect to, do your experimenting off the Hub.

There is a bunch of different nets about many subjects…participate.

And please remember…..if you are having issues or questions ask any number of folks on the air ( text or call me )that can help you.

The main objective, like all the other aspects of ham radio is to have FUN.

 

 

____________________________________________________________________________________________________________________

August 8,2021

H2 trip

Participants:  Ryan K7JABK, Mike KS7URV, Lawrence N6YFN

Completed Items:

  • Reinstalled the Allstar node after Raspberry Pi and SD card were replaced by Earl WB6AMT
  • Installed TrippLite IS1000 power isolation transformer/surge suppressor.
  • Installed Furman rack mount power strip donated by Mike KS7URV.
  • Removed all of the individual plastic power strips.  Routed and wired all AC cords in our rack into the Furman.  The Furman was then plugged into the output of the TrippLite isolation transformer.
  • Tested shack wall outlet (OK).  Plugged Tripplite isolation transformer into wall.
  • Replaced Cisco VPN router with newer model RV160.  We how have access to Motorola Repeater Diagnostic and Control (RDAC) again.
  • Checked all components for power on and operation including other racks at the site
  • Checked Allstar and network connectivity, including the N1 node.
  • Installed property tags all W7HEN components
  • Installed batteries in WX station display unit to maintain date/time in case of power failure
  • Reinstalled deadbolt strike plate
  • Confirmed this morning (Sunday 8/8) via RDAC that no alarms are present on H2 and SWR is at 1.17:1

 

Pending items

  • Power hum is still present in H2 audio output.  This hum is not transmitted out to the Allstar network.  Tested unplugging individual devices one by one.  Tried running the 12V network power supply off of battery, but hum still existed.  Also tried running repeater off of battery but hum still existed.  Unplugging all other AC devices (PoE injectors, etc) reduced hum slightly but did not eliminate the hum.  The only way hum would completely go away is with the entire rack unplugged from the wall and completely and running off batteries.   As observed during Pi failure, when repeater is running standalone (internal controller) with nothing plugged into the accessory port (no audio routing through external controller), there is no hum present.
  • Recommend re-examining hum situation again when we have time.  Possibly using some strategic ground lifts. Possibly rewiring entire rack to use a common 12VDC power plant similar to Low Potosi.
  • The Ethernet network data switch has lost its VLAN configuration.  This is not impacting normal operations, but VLANs will need to be setup again to enable Allstar connectivity to the Hub via the mesh network if Cox has an outage.  Lawrence will investigate and try reloading configuration remotely, but only if it can be done safely.

 

H1 trip

Participants:  Mike KS7URV, Tony WB6MIE, Dave KF7JAF, Lawrence N6YFN

Completed items:

  • Using laptop confirmed with locally connected RDAC that repeater was operating at full power and not seeing significant SWR (1.2:1)
  • Tony noticed that the H1 isolator was warm to the touch.  Removed isolator and observed 1.7:1 SWR via RDAC
  • Temporarily swapped antennas with D-Star and made several test calls to members in NLV and 7 Hills area.  Observed good SWR and coverage with the DB411 when running on the H1 repeater.  Returned the DB411 antenna to the D-Star repeater.
  • Used Bird meter to further diagnose SWR and power output from H1 repeater.
  • Went on roof and inserted Bird meter at the jumper before it fed into the Stationmaster antenna.   Determined that with isolator installed, RF was not passing to antenna. 
  • Removed isolator and retested with Bird meter.  Observed full power output at antenna and acceptable SWR.
  • Reconnected and re-waterproofed rooftop jumper going into antenna.  Using RDAC observed an SWR of 1.4:1 without the isolator.
  • Conducted additional testing with NLV club members.  Reception was similar to previous (pre failure) levels but not quite as strong as when the DB411 was connected to H1.
  • VPN RDAC router was previously locked up and not passing traffic.  Rebooted and checked configuration in VPN RDAC router.  Now saw good connection back to the Hub.
  • Reconfigured IP site connect settings in the repeater to allow direct RDAC monitoring so as not reliant on H2 passthrough.  Confirmed via RDP into the RDAC software running at the Hub that RDAC was now working to H1.
  • Checked all equipment for power on and normal operation
  • Confirmed this morning (Sunday 8/8) via RDAC that no alarms are present on H1 and SWR is at 1.39:1

 

Pending Items:

  • Need to evaluate and price a replacement isolator for H1 to replace the “free” donated unit that failed.
  • Need to evaluate if a different antenna should be considered in the future for H1 with alternative mounting location and directional properties to possibly provide better coverage into the valley.

 

 

___________________________________________________________________________________________________________________

August 1, 2021

“How and why using commercial two-way radios on the ham bands”

The big question…

Heard on this subject is WHY and How do I do it?

I will be the first to admit that putting an old commercial radio on the air isn’t as easy as picking a radio up at Gigaparts or Ham Radio Outlet, that’s why it’s not for everyone.

 

PROS…

  • QUALITY (Construction, parts)

  • LIFE EXPECTANCY

  • ACCESSORIES AVAILABLE

  • USED PRICES

  • SERVICEABLE

  • PROGRAM CAPABILITY

  • ANALOG & DMR

  • CREATABLE ZONES TO MANAGE THE 1000 CHANNELS

CONS…

  • LACK OF MANUFACTURERS SUPPORT

  • LACK OF ACCESSORIES

  • ACCESSORIES CAN BE EXPENSIVE COMPARED TO OEM

  • LACK OF SERVICE PEOPLE

  • ON ONE BAND ONLY (THERE IS AN EXCEPTION)

  • NUMBER OF CHANNELS

  • PROGRAMMING SOFTWARE

  • USES CRYTALS ( CURRENT PRICE $100 MIN.)

A little background…

#1 Older radios on ebay

 MaxTrac  (typical age – 35+ yrs old, typical price $20.00)

5abd91dada184bd6c53c9a3f383ca7de

 

#1A  XPR4550 

IMG_20210801_133003169

 

#1B  XPR 5550 Analog and DMR Mobile

 

IMG_20210801_134045532

Programming software for these XPR series radios are available from Motorola Solutions to purchase at this time.

 

#1C M1225  Current prices  $25-40, it does take an older CPS to program but can be done.

   IMG_20210801_133958903

           This is a 4 channel VHF 45 watt radio

 

 

#2 XPR6550  (Very popular among hams)

6550

 

2A XPR

#3 Batteries

20200524_142514_Film3

 

#4 Mobile Chargers & other Accessories

20200524_142142_Film3

 

#4A  Xpr7550 1000 channel HT

IMG_20210801_133814312

 

#5 Microphones for XPR series mobile radios

IMG_20210801_133036117

 

#5A  XPR Noise-Cancelling microphone

IMG_20210801_134059044

 

#5B  XPR DTMF microphone

IMG_20210801_133126550

 

 

#6 What  $100 will get you.  (your brand may vary)

Wouxun

 

Quality components- (survivability after drop test)

Performance- (drop test)

Price- $25 on up

Service ability- (after drop test)

 

#6A Spurious emissions (after 3Ft drop test back in Jan 2014)

spurious-emissions1

 

#7 Spurious emissions (commercial radio after 3Ft drop)

s-l640

 

 

#8

The bottom line for me has been that using a commercial radio in Amateur service must be like “Baby’ing” it in comparison to what they were designed to go thru 8+ hours a day for years on end…your wear may vary!

31344958_10157326585654863_3560128525144948736_n

        AND STILL GOT THE JOB DONE!

( The story behind why the above radio was finally brought to the service shop was “sometimes it would sting his forehead WHEN NOT USING THE MICROPHONE while talking on the radio”.

If you have any questions about using commercial radios on the ham bands contact myself or a plethora of hams on our network that use older two-way radios on the ham bands.

Not only are most used items a good deal but you will get your money’s worth out of them.

These older radios were build with a 10 to 20 year life cycle, that you can count on years of outstanding rough service that many of the newer stuff may not be able to give.

That old saying holds true….“YOUR OWN MILEAGE MAY VERY”

 

73

WB6AMT

 

————————————————————————————————————————

July 25, 2021

“What does the Touch-tone buttons on your HT do?”

On November 18, 1963, the first electronic push-button system with touchtone dialing was commercially offered by Bell Telephone to customers in the Pittsburgh.

John E. Karlin, a New Jersey man is credited with inventing the keypad on phones and ATMs.

 

#1  Frequencies

DTMF-Keypad-Layout

 

#1A  Single Tone & Dual Tone

dowsingle tonedymf wave

 

#2  Examples – Encodersty__90555.1522962981.1280.1280

 

#2A  4X4 keypad switch

40552627

 

#2B  16 button MA Bell touch-tone encoder pad

TelcoPad

 

#2C  DTMF encoder intergrated circuits

#3 Encoder ICs2559_5089freqs

 

#4 TelcoEncoder Schematic

ttpad

 

#5 DTMF Decoders – Telco KT-247B247b

 

#5A DTMF Decoder – Telco  LC  type

Decoder

 

#5B Decoder MT8870 type

MT8870

 

#6 Decoder Schematic – MT8870 ICimages

 

Anyone can use Touch-tone or DTMF tones to provide switching functions to many differetnt circuits.

Radio transmitter, wireline telephone circuits, actually just about any medium that can pass voice range audio can be used to send DTMF tones to a decoder.

It is a stable and precision form of tone generation.

Your imagination is the limit to your switching or control projects.

 

73 WB6AMT

 

___________________________________________________________________________________________________________________

June 13, 2021

“Ask the Pros” night

 

_______________________________________________________________

June 6,2021

But first a couple pictures of electronic equipment…..

1718752b14b9e58f2ff8d8b4c9408253

This is from a late 1980’s Popular Electronics issue….we have come along way BABY!

 

MOTOROLA’s first trunk mount mobile telephone.

1st_mobilephone

 

All about the 18650 Lithium ion battery (almost)

For informational purposes only. Use caution when working with any batteries.

Anyone doing anything that is shown here tonight, is doing it on their own and I am not responsible for your actions or outcomes.

Keep in mind that not using a battery correctly or not following proper charging specifications can result in burns, fire, cells rupturing (exploding) and damage to your equipment that the battery is installed in.

First thing…when dealing with and handing batteries, wear eye protection and always exercise cautious handing with all batteries and prevent the terminals from shorting against any metal objects by their terminals.

DO NOT DAMAGE THIS TYPE OF BATTERY CELL, or any battery for that matter!!

Those not agreeing with some of the information here or wanting to add to the discussion, that is what our question and comments are for, do participate.

I am NOT an expert on the Lithium-ion battery chemistry make-up, but I do attempt to know as much as I can when working with electronic components….including batteries. This where most of tonight’s information is from, my research and experimenting.

To be able to cover as much as possible on the different aspects of the 18650 please go online to dig deeper into the facts that will be touched on tonight.

 

Some concerns of the popular 18650 Lithium-ion battery to be discussed.

ARE THEY SAFE?

POPULARITY – ( what do they replace)

The new King of the Hill in batteries. Automotive uses.

 

TWO TYPES AVAILABLE – (what is BMS)

The two types of lithium-ion cells are called PROTECTED and NON-PROTECTED

NON-PROTECTED are strictly the cells without a BMS (Battery Management System)

PROTECTED Cells have a BMS circuit board (normally on the bottom end of the cell).

Larger battery packs will have the circuit board under the shrink wrap of the battery pack.

#1  Some different type of BMS  circuit boards.

s-l1000

  • Besides protecting your cells from being overcharged and over-discharged, over temperature, they will also try to keep all your cells voltage to be at the same value. This is called cell balancing.

  • #2 Typical hookup of the cells to the BMS

  • s-l300

WHEN IS AN 18650 CHARGED –

Nominal voltage is 3.6-3.7 volts.

A charged 18650 is 4.2 volts and a cell is considered discharged at 3.3 volts. 

 

#3  REAL QUALITY AND FAKE 18650 BATTERIES –

The big four quality 18650 manufacturers are SONY, SAMSUNG, SANYO & LG.

maxresdefault (1)

Often times you can determine real from fake or counterfeit battery is by downloading the datasheet for the battery you have and note the weight.

The best confirmed capacity original cell at this point has 3400mAh.

Second, their weight is lighter. Original cells are 45grams+. Fakes have mostly under 40g, and the worst quality ones are even 20g. Those have an effective capacity of under 500mAh, even if they state 4000mAh+ on the label.

And there’s also the 99.998% fakes called Ultrafire. Practically, all Ultrafire cells on the online market that state any capacity over 3000mAh are fakes. Since there are other fake cells with fake-stated capacity, they have stated capacities of over 4000mAh, which is not currently possible.

 

HOW TO TELL BATTERY CURRENT SIZE BY COLOR –

SAMSUNG

Most Samsung cells in circulation are kind of Cyan color. Note that other smaller companies use this color, but only the Samsung’s have Samsung written on them.

Here is the color (light green) I’m talking about – in this picture we have a 2000mAh cell. Same color can be found for 2200mAh (most common) and 2400mAh.

samsung2000

Since for 2000,2200 and 2400 mAh cell things can get confusing when it comes to colors, the best way to identify capacity is from the end of the line number in the first text line on the cell (the row where it says 18650). As you can see in the pictures, that’s exactly what 20,22,24,26 and 30 mean – it’s the capacity tag for any Samsung cells. So you can now identify any Samsung cell.

 

SANYO

Most Sanyo cells are RED (RGB: 255,0,0), or the new fakeRED (RGB: 255,0,64) that’s infested with blue (we’ll talk about that later). They are the most hard to identify overall.

This is how a real red cell suppose to look like (RGB: 255,0,0):

The 2000mAh original ones are indeed red by any standards. The cap is white. So if it’s pure red ones it’s 2000mAh capacity. The newer ones were also fakered, but the cap is still white.
Here they are:

The 2200mAh cells and above are fakered. It’s hard to detect in a picture, but there’s a clear tendency towards purple for those.
sanyo2200
You can tell the cells that have 2200mAh capacity be the RED cap. The cap is true red, unlike the rest of the cell.
The 2600mAh ones are also fakered, but those have cyan cap.
sanyo2600

The high power cells (like the high current 1500mAh ones used in power tools) have a pink or light blue cap.
So, to identify the Sanyo cell, you’ll have to use actual color nuance and cap color, since the series written on them are most of the time barely visible.

 

SONY

Sony are standard green. All of them are the same green. The way to identify them is the G-number.
On the second line, the first number after the G is the capacity identifier.

sony2400

 

 

LG

The good thing is that they can be identified very easy by color.

The 2000mAh cells are pale orange.

18650

The 2200mAh are grey. They are still one of the most common LG batteries.
lg2200

Probably the most used LG cell today is the 2600mAh one which is orange.
lg2600

LG also has some new cells rated at 3100mAh.
lg3100

Each manufacturer has a trick: for Samsung you have to check the tag at the end of the line, for Sanyo the cap color and for Sony the G-spot and for LG just the cell color.

 

HOW TO SOLDER 18650 BATTERIES TOGETHER –

First off, that’s why they make batteries with solder tabs. However…

If you are going to solder on to 18650’s, here is some tips for success…..Chemical contact.

  1. Use a 60 watt soldering iron with a chisel or conical tip at least 1/8″ wide.

  2. Silver-Bearing  (62/36/2) solder or at least a quality 60/40 solder.

  3. Using a sandpaper or a fine file, scuff the surface you are going to solder. About an 1/8″ is big enough

  4. Tin the wire that your going to attach.

  5. While holding the wire down on the scuffed area firmly, apply a small amount of solder, it should flow immediately. Remove the iron, not moving the wire.

  6. This should only take about 1/4 second, if the solder doesn’t want to flow as described, your iron tip is loosing it’s heat and is probably to small for the job.

 

 

HOW TO FIX A NON-CHARGEABLE BATTERY ( Less than +2 volts)

When an 18650 battery always shows that it is not charging or charged (normally a green light) but has a voltage of 2 volts can cause the charger to misread the battery and over-charge causing over-heating.

With a properly charged good battery (measure +4.2 volts) you can sometimes jump start a cell by connecting the good cell (same type and size) with a pair of clip leads to your SICK battery for no more than 20 seconds. Positive to positive and negative to negative, while feeling the batteries for over-heating. The battery being jump charged may be a little warm. Measure the battery voltage and if it is over 3 volts, cycle it through a charge cycle in your charger.

Often times you have just resurrected your battery back from the dead.

When charging lithium-ion cells always check and see that they are not overly hot, as cells go bad they develope chemical issues that can cause excessive heat and internal gases to build up.

When in doubt, if they are out of waranty…to be on the safe side…..trash them.

 

 

WHAT IS A CID – HOW TO FIX AN OPEN 18650 BATTERY (0.0 VOLTS)

For informational purposes only, this is from my own experimenting and not recommended by others.

DSCN2025

cid

For a video, go to https://www.youtube.com/watch?v=1w3Tv1Jg0ps

 

Quality 18650 battery chargers –

18650 Chargers

DSCN2026

DSCN2027

Here is a downloadable nine page document with additional information about the 18650 battery :

18650 Cells

Google 18650 batteries for more ( a LOT more) data on this new KING of The HILL in batteries.

If you are going to experiment…remeber to use extreme caution when working with theses cells they have a great deal of potential.

See you next week!

 

_______________________________________________________________________________________________

May 23, 2021

  • How does Allstar work?

  • More importantly, what is it really?

A simple description of “Allstar”:

This is a way of connecting a ham radio to another ham radio by using a Internet connection taking advantage of a {VoIP} Voice over Internet Protocal device.

This device of which we speak is called an Allstar Node.

 

What is VoIP?

VoIP is an acronym for Voice over Internet Protocol that describes the method to place and receive phone calls over the internet. Most people consider VoIP the alternative to the local telephone company.

If you’ve heard of an IP address, that’s your Internet Protocol address. An IP address is how computers and devices communicate with each other on the internet.

VoIP isn’t actually all that new. Telephony has relied on digital lines to carry phone calls since the late 90s.

VoIP is a cost-effective way to handle an unlimited number of calls. This requires that you have a VoIP Carrier to provide yopu with the ability to make and connect calls to other telephopnes in the world whether they are VoIP or regular Telephone subscribers.

Now days almost all of the telephone service available thru a phone carrier is Voip because it illiminates the need for Cat3 telephone lines. Internet service is available to over 94% of the entire United States at this time and covers a great deal of the world ( statitics unknown at this time).

How does that work for me as a ham radio operator?

Using that same technology of converting sound into data packets, we can send these data packets down the internet to make a connection to another Allstar node.

With an Allstar node, when you power up your device, part of the booting up process, (when your running Hamvoip on the Allstar node) sends data packets to AllStarlink.org.

At this point I need to tell you that you have to register with Allstarlink.org and request to get your own node number to be able to take advantage of the Allstarlink.org service.

This starts an Allstar Session and indicates back to you that you are now able to connect to any other Allstar Node that is currently active at that time.

When you start a new session (Boot up your Hamvoip device) once the program has loaded into your Rasp Pi and is running, you will hear your node readout the registered call sign and if you are connected to the internet it will read back your IP address. This IP address is what Allstar link has registered for that session and is what it will connect to.

Below is the bubble chart for Node #44045. This is the HARC Allstar Hub and can take incoming connections at anytime that internet service is available. At times when there is an issue with the internet, it will effect the ability to send or receive connections.

bubblechart

This is a bubble chart showing the current Allstar nodes that are connected to the HARC Allstar hub at 3:16pm this afternoon. http://stats.allstarlink.org/getstatus.cgi?44045

This is how we connect the repeaters to one another as a linked system using Allstar nodes at each repeater.

Shown is H1 repeater, H2 repeater with C1 in California connected to H2, H5 in Pahrumpt as well as other stations connected to the hub like NO7E node, WA6FSJ in Yucca Valley, N2DKI in henderson and the Echolink node. All these nodes are connected to the hub and can “talk” to each other simultaneously.

It looks very much like an older telephone party line systems, where anyone connected could hear what anyone else was saying during a phone call.

Operating an Allstar node is very much like making a phone call, it’s point to point connection done by sending DTMF Touch-tones to a server (Allstarlink.org), indicating who you want to connect to, if the node is active, you will be connected. It’s that simple.

Like any other thing in ham radio there are those who attempt to make it bigger…better…more options, more complicated etc.

I’m going to show you how simple an Allstar node can be with a minimum of required components.

(Keep an eye out at the end…)

 

#1Allstar_Block

 

#1A Schematic of Radioless nodeRadioless Node print

 

#2  Parts of a node20190817_181727_Film3[1]

Above is a demostration board built to show what is needed to make an operational Allstar node for the National Association of Broadcasters 3 yrs ago.

NAB Handout

 

#3   Typical Allstar node/Repeater controller20181005_013551_Film4

            Allstar node located at Pleasants Pk., California WB6MIE repeater 446.120MHz

 

#4  USB Radio Interface ra40-top        An RA40 USB Radio Interface board from Masters Communication (Built or kit form)

 

#5 RA40 SchematicRA40_sche

                   The stars indicate connections to your radio or radioless connections.

 

#6  5Volt regulated power supply board

DSCN2340

 

#6A  A smaller version of above without a meter

5Amp Regulator brd

 

#7  SA-818 Radio ModuleDSCN2225

 

 

#8 What is the difference between Raspberry Pi 3 and B+?

Hardware improvements from the Pi 3 to Pi 3 B+

The Pi 3 Model B+ is based on the same quad-core, 64-bit processor, as the Pi 3Model B. Like the Model B, the B+’s is based on a Arm Cortex A53 architecture. However, the B+ ups the speed of the CPU to 1.4GHz from 1.2GHz in the original Model B, an increase of 16.7%.Mar 14, 2018

Back in 2017 the club had a club project where everyone built an allstar node using a Rasp Pi, a DMK Uri interface, and an SA818 radio module.Micro UHF Radio Dongle Construction (12-4-17)

This project was spearheaded by Lawrence N6YFN and was the author of the document.

This got many stations on the air with Allstar that had severe issues with antennas from their HOA’s. This was solution to them being able to get on the air without an external antenna.

We no longer use DMK Uri’s because of the high failure rate and the lack of support from the manufacturer.

I’m including the document here because it is a wealth of info on how to build a node and the setup information is still valid.

 

And Another way to build a node…

Headset allstar node

I have received this headset this week and plugged it into a Rasp Pi running Hamvoip and it works and sounds excellent, no muss….no fuss, however to control the node and connect to others you do have to install “NODE REMOTE”  as explained in the article on your cell to be able to control the node with your cell phone.

If you have any additional questions or comments about this topic, contact me at wb6amt@cox.net.

 

73 Earl

 

————————————————————————————————————————-

 

____________________________________________________________________________________________________________________

May 9, 2021

“The Uncertain Future of Ham Radio”

An open discussion with WB6AMT and EVERYONE.

I would like to get everyone’s take on the following observations.

Will the amateur airwaves fall silent?

Since the dawn of radio, amateur operators—hams—have transmitted on tenaciously guarded slices of spectrum. Electronic engineering has benefited tremendously from their activity, from the level of the individual engineer to the entire field. But the rise of the Internet in the 1990s, with its ability to easily connect billions of people, captured the attention of many potential hams. Now, with time taking its toll on the ranks of operators, new technologies offer opportunities to revitalize amateur radio, even if in a form that previous generations might not recognize.

The number of U.S. amateur licenses has held at an anemic 1 percent annual growth for the past few years, with about 7,000 new licensees added every year for a total of 755,430 in 2018. The U.S. Federal Communications Commission doesn’t track demographic data of operators, but anecdotally, white men in their 60s and 70s make up much of the population. As these baby boomers age out, the fear is that there are too few young people to sustain the hobby.

 

“Here is the $64,000 question: How do we get the kids involved?” 

This question of how to attract younger operators also reveals deep divides in the ham community about the future of amateur radio. Like any large population, ham enthusiasts are no monolith; their opinions and outlooks on the decades to come vary widely. And emerging digital technologies are exacerbating these divides: Some hams see them as the future of amateur radio, while others grouse that they are eviscerating some of the best things about it.

No matter where how you feel about Ham Radio’s future, everyone understands one fact.

The world is changing; the amount of spectrum is not.

And it will be hard to argue that spectrum reserved for amateur use and experimentation should not be sold off to commercial users if hardly any amateurs are taking advantage of it.

Before we look to the future, let’s examine the current state of play. In the United States, the ARRL, as the national association for hams, is at the forefront, and with more than 160,000 members it is the largest group of radio amateurs in the world. The 106-year-old organization offers educational courses for hams; holds contests where operators compete on the basis of, say, making the most long-distance contacts in 48 hours; trains emergency communicators for disasters; lobbies to protect amateur radio’s spectrum allocation; and more.

#1

#1Photo: ARRL Former ARRL CEO Howard Michel (WB2ITX) at headquarters station, W1AW.

 

Michel led the ARRL between October 2018 and January 2020, and he fits easily the profile of the “average” American ham: The 66-year-old from Dartmouth, Mass., credits his career in electrical and computer engineering to an early interest in amateur radio. He received his call sign, WB2ITX, 50 years ago and has loved the hobby ever since.

“When our president goes around to speak to groups, he’ll ask, ‘How many people here are under 20 [years old]?’ In a group of 100 people, he might get one raising their hand,” Michel says.

 

#2

#3

Ronny Risinger (KC5EES) Members from the LASA High School Amateur Radio Club, K5LBJ, in Austin, Texas participated in School Club Roundup, a twice-yearly on-air event that encourages participation from ham radio school groups.  

The ARRL group runs twice-annual Kids Day events, fosters contacts with school clubs across the country, and publishes resources for teachers to lead radio-centric classroom activities. But Michel readily admits “we don’t have the resources to go out to middle schools”—which are key for piquing children’s interest.

We need to “convince them there’s more than getting licensed and putting a radio in your drawer and waiting for the end of the world.”

Sustained interest is essential because potential hams must clear a particular barrier before they can take to the airwaves: a licensing exam. Licensing requirements vary—in the United States no license is required to listen to ham radio signals—but every country requires operators to demonstrate some technical knowledge and an understanding of the relevant regulations before they can get a registered call sign and begin transmitting.

For those younger people who are drawn to ham radio, up to those in their 30s and 40s, the primary motivating factor is different from that of their predecessors. With the Internet and social media services like WhatsApp and Facebook, they don’t need a transceiver to talk with someone halfway around the world (a big attraction in the days before email and cheap long-distance phone calls). Instead, many are interested in the capacity for public service, such as providing communications in the wake of a disaster, or event comms for activities like city marathons.

“There’s something about this post-9/11 group, having grown up with technology. Michel says. “They see how fragile cellphone infrastructure can be. What we need to do is convince them there’s more than getting licensed and putting a radio in your drawer and waiting for the end of the world.”

Questions

 

New Frontiers

#4

Sateesh Nallamothu Dhruv Rebba (KC9ZJX) with memorabilia from his ham radio contact with astronaut Joe Acaba (KE5DAR) onboard the International Space Station.

Rebba earned his technician class license when he was 9, after having visited the annual Dayton Hamvention with his father. (In the United States, there are currently three levels of amateur radio license, issued after completing a written exam for each—technician, general, and extra. Higher levels give operators access to more radio spectrum.)

The future lies in operators like Dhruv Rebba (KC9ZJX), who won Amateur Radio Newsline’s 2019 Young Ham of the Year award. He’s the 15-year-old son of immigrants from India and a sophomore at Normal Community High School in Illinois, where he also runs varsity cross-country and is active in the Future Business Leaders of America and robotics clubs. And he’s most interested in using amateur radio bands to communicate with astronauts in space.

His dad had a significant influence on him regarding amateur radio, he thought it was really cool,” Rebba says. “It was something my friends weren’t doing.”

Rebba found a way to combine ham radio with his passion for space: He learned about the Amateur Radio on the International Space Station (ARISS) program, managed by an international consortium of amateur radio organizations, which allows students to apply to speak directly with crew members onboard the ISS. (There is also an automated digital transponder on the ISS that allows hams to ping the station as it orbits.)

Rebba rallied his principal, science teacher, and classmates at Chiddix Junior High, and on 23 October 2017, they made contact with astronaut Joe Acaba (KE5DAR). For Rebba, who served as lead control operator, it was a crystallizing moment.

“The younger generation would be more interested in emergency communications and the space aspect, I think. We want to be making an impact,” Rebba says. “The hobby aspect is great, but a lot of my friends would argue it’s quite easy to talk to people overseas with texting and everything, so it’s kind of lost its magic.”

That statement might break the hearts of some of the more experienced hams recalling their tinkering time in their childhood basements. But some older operators welcome the change.

Take Bob Heil (K9EID), the famed sound engineer who created touring systems and audio equipment for acts including the Who, the Grateful Dead, and Peter Frampton. His company Heil Sound, also manufactures amateur radio technology.

“I’d say wake up and smell the roses and see what ham radio is doing for emergencies!” Heil says cheerfully. “Dhruv and all of these kids are doing incredible things. They love that they can plug a kit the size of a cigar box into a computer and the screen becomes a ham radio…. It’s all getting mixed together and it’s wonderful.”

But there are other hams who think that the amateur radio community needs to be much more actively courting change if it is to survive. Sterling Mann (N0SSC), himself a millennial at age 27, wrote on his blog that “Millennials Are Killing Ham Radio.”

 

#5

#6

Sterling Mann (N0SSC) is advocating that ham radio shift away from a focus on person-to-person contacts.

It’s a clickbait title, Mann admits: His blog post focuses on the challenge of balancing support for the dominant, graying ham population while pulling in younger people too. “The target demographic of every single amateur radio show, podcast, club, media outlet, society, magazine, live streams, or otherwise, is not young people,” he wrote.

To capture the interest of young people, he urges that ham radio give up its century-long focus on person-to-person contacts in favor of activities where human to machine, or machine to machine, communication is the focus.

These differing interests are manifesting in something of an analog-to-digital technological divide. As Spectrum reported in July 2019, one of the key debates in ham radio is its main function in the future:

Is it a social hobby?

A utility to deliver data traffic?

And who gets to decide?

Those questions have no definitive or immediate answers, but they cut to the core of the future of ham radio.

Questions

Loring Kutchins (W3QA), president of the Amateur Radio Safety Foundation, Inc. (ARSFi)—which funds and guides the “global radio email” system Winlink—says the divide between hobbyists and utilitarians seems to come down to age.

“Ham radio is really a social hobby…Here in Mississippi, you get to 5 or 6 o’ clock and you have a big network going on and on—some of them are half-drunk chattin’ with you.”

“Younger people who have come along tend to see amateur radio as a service, as it’s defined by FCC rules, which outline the purpose of amateur radio—especially as it relates to emergency operations,” Kutchins (W3QA) told Spectrum last year.

Kutchins, 68, expanded on the theme in a recent interview: “The people of my era will be gone—the people who got into it when it was magic to tune into Radio Moscow as a SWL ( short wave listener). But Grandpa’s ham radio set isn’t that big a deal compared to today’s technology. That doesn’t have to be sad. That’s normal.”

Gramps’ radios are certainly still around, however. “Ham radio is really a social hobby, or it has been a very social hobby—the rag-chewing has historically been the big part of it,” says Martin F. Jue (K5FLU), founder of radio accessories maker MFJ Enterprises. “Here in Mississippi, you get to 5 or 6 o’ clock and you have a big network going on and on—some of them are half-drunk chattin’ with you. It’s a social group, and they won’t even talk to you unless you’re in the group.”

#6#7

 

Martin F. Jue (K5FLU), founder of well-known radio accessories maker MFJ, is developing new products to accommodate the shift towards digital radio communications in the amateur bands. “It’ll all be digital at some point, right at the antenna all the way until it becomes audio.”

But Jue, 76, notes the ham radio space has fragmented significantly beyond rag-chewing and DXing, and he credits the shift to digital. That’s where MFJ has moved from its antenna-heavy catalog of products.

“Ham radio is connected to the Internet now, where with a simple inexpensive handheld walkie-talkie and through the repeater systems connected to the Internet, you’re set to go,” he says. “You don’t need a HF [high-frequency] radio with a huge antenna to talk to people anywhere in the world anymore.”

“Some folks can’t put up an antenna because of the increase of HOA conditions, but that doesn’t matter anymore because they can use somebody else’s radio through these RigPis and similar Voip equipment,” Jue says.

“It’s all going more and more toward digital modes,” Jue says. “In terms of equipment I think it’ll all be digital at some point, right at the antenna all the way until it becomes audio.”

Questions

The Signal From Overseas

Outside the United States, there are some notable bright spots, according to Dave Sumner (K1ZZ), secretary of the International Amateur Radio Union (IARU). This collective of national amateur radio associations around the globe represents hams’ interests to the International Telecommunication Union (ITU), a specialized United Nations agency that allocates and manages spectrum. In fact, in China, Indonesia, and Thailand, amateur radio is positively booming, Sumner says.

China’s advancing technology and growing middle class, with disposable income, has led to a “dramatic” increase in operators, Sumner says. Indonesia is subject to natural disasters as an island nation, spurring interest in emergency communication, and its president is a licensed operator. Trends in Thailand are less clear, Sumner says, but he believes here, too, that a desire to build community response teams is driving curiosity about ham radio.

“So,” Sumner says, “you have to be careful not to subscribe to the notion that it’s all collapsing everywhere.”

China is also changing the game in other ways, putting cheap radios on the market. A few years ago, an entry-level handheld UHF/VHF radio cost around US $100. Now, thanks to Chinese manufacturers like Baofeng, you can get one for under $25. HF radios are changing, too, with the rise of software-defined radio.

“It’s the low-cost radios that have changed ham radio and the future thereof, and will continue to do so,” says Jeff Crispino, CEO of Nooelec, a company in Wheatfield, N.Y., that makes test equipment and software-defined radios, where demodulating a signal is done in code, not hardwired electronics. “SDR was originally primarily for military operations because they were the only ones who could afford it, but over the past 10 years, this stuff has trickled down to become $20 if you want.” Activities like plane and boat tracking, and weather satellite communication, were “unheard of with analog” but are made much easier with SDR equipment, Crispino says.

Questions

Nooelec often hears from customers about how they’re leveraging the company’s products. For example, about 120 members from the group Space Australia to collect data from the Milky Way as a community project. They are using an SDR and a low-noise amplifier from Nooelec with a homemade horn antenna to detect the radio signal from interstellar clouds of hydrogen gas.

It is an increasingly fragmented space,” Crispino says. “But I don’t think that has negative connotations. When you can pull in totally unique perspectives, you get unique applications. And this could be a hook to get more young people interested.

The ham universe is affected by the world around it—by culture, by technology, by climate change, by the emergence of a new generation. And amateur radio enthusiasts are a varied and vibrant community of millions of operators, new and experienced and old and young, into robotics or chatting or contesting or emergency communications, excited or nervous or pessimistic or upbeat about what ham radio will look like decades from now.

As Michel, the former ARRL CEO, puts it: “Every ham has [their] own perspective. What we’ve learned over the hundred-plus years is that there will always be these battles—AM modulation versus single-sideband modulation, whatever it may be. The technology evolves. And the marketplace will follow where the interests lie.

Questions

 

I’m hoping that even if you did not have any questions or comments tonight that we can all agree, ham radio needs for its licensed hams to try to do a little more to reach out and see if we can get more young folks drawn to this hobby.  Old people interested in becoming users of amateur radio to further a career, spark an interest in school or become an active member of their community by providing services when needed, such as being a communicator at a local hospital for the Red Cross or during a Bike-A-thon event, and even race car events, etc.

 

DE WB6AMT

________________________________________________________

May 2, 2021

“Starlink Satellite Internet Service”

By Tony Dinkel – WB6MIE

 

High-speed, low latency broadband internet.

Starlink is now delivering initial beta service both domestically and internationally, and will continue expansion to near global coverage of the populated world in 2021.

During beta, users can expect to see data speeds vary from 50Mb/s to 150Mb/s and latency from 20ms to 40ms in most locations over the next several months as we enhance the Starlink system. There will also be brief periods of no connectivity at all.

As we launch more satellites, install more ground stations and improve our networking software, data speed, latency and uptime will improve dramatically.

 

Finally arrived

signal-2021-04-29-131447

 

All in one box

signal-2021-04-29-131447 (1)

 

signal-2021-04-29-131447 (3)

 

Instructions

signal-2021-04-29-131447 (2)

 

Setting Up

starlink stowed 2

 

Operating after acquired satellite

starlink operating

 

Snip20210502_30

 

Snip20210502_31

Statistics

starlink stats p1

 

Sector coverage

1_network_internet_connected_grid_earth_power_satellite-view-100769192-large

 

Planned constillation

Starlink1

 

Starlink Train

starlink-satellite-train

 

Deploying  1

starlink deploy 1

 

Deploying  2

starlink deploy 2

 

Deploying  3

starlink deploy 3

 

Deploying  4

starlink deploy 4

 

Deploying  5

starlink deploy 5

 

Deploying  6

starlink deploy 6

 

 

 

____________________________________________________________

April 25, 2021

“Using phonetics on VHF/UHF repeaters”

By WB6AMT

 

Using phonetics on VHF and UHF repeaters has always been a active conversation topic since the 1970’s when I first became involved with 2 mtrs an radio clubs.

Tonight’s discussion is meant to get everyone’s opinio0n and thoughts on this. Does it work for you and the way you operate  on the repeaters.

So long as you identify your station with your call letters only, you are operating the way part 97 outlines proper behavior on the amateur bands.

I’ll be calling on all check-ins tonight, so that everyone can express their thoughts, ideas and feelings about this.

First a little background about how these discussions originally came about.

In the early 60’s and 70’s police departments were switching from low band radios around 30Mhz and were exploring the new VHF radios in the 50Mhz and vhf 151Mhz radios. 

This was actually very good for hams as newer models with more channels were sold to the business and commercial customers, this created a flood of surplus equipment available that hams quickly scooped up.

These hams were often referred to as techies by the older HF radio operators, because a lot of them were familiar with business band radio customers and these tube radios were as easily to get on the ham bands as ordering new crystals and doing a re-alignment.

At this time southern California was called the birth place of 2 meter vhf FM radios due to the shear numbers of radios that exploded on to the ham scene.

AM repeaters had been put into ham servbice and folks could see the benefit of this type of operation by placing radios on mountaintops and commercial antenna propogation.

But just like the broadcast radio stations, it was discovered that FM radios were very quiet and the audio was excellent to listen to in the mobile or on any two-way radio at the time.

As FM repeater clubs started and grew, the HF operators started to get on the air on 6 meters and 2 meters bringing with them the heavy use of Phonetics when identifying.

There was organized situations that called for the use of phonetics exclusively, however stations involved in commercial operations felt that this practice was taking a lot of air-time when just giving the call letters would be less time consuming and easier to understand because we are no longer listening to static and interference mixed with your audio, but audio coming thru the repeater was actually about as clear as talking to someone face to face or on a telephone. +++

All the FCC expects us to do is identify with our callsign only at the proper times. Every 10 minutes in a qso and at the end of a transmission.

An example of “end of transmission” is …Test 1..2..3.. WB6AMT, release PTT button.

 

Letter Word Pronounced as

A    Alfa    AL FAH
B    Bravo  BRAH VOH

C    Charlie    CHAR LEE or SHAR LEE
D   Delta    DELL TAH

E    Echo     ECK OH
F    Foxtrot   FOKS TROT

G   Golf    GOLF
H   Hotel   HOH TELL

I    India    IN DEE AH
J   Juliett   JEW LEE ETT

K   Kilo    KEY LOH
L   Lima   LEE MAH

M   Mike     MIKE
N   November    NO VEM BER

O   Oscar   OSS CAH
P   Papa    PAH PAH

Q   Quebec   KEH BECK
R   Romeo    ROW ME OH

S    Sierra     SEE AIR RAH
T    Tango    TANG GO

U   Uniform    YOU NEE FORM or OO NEE FORM
V   Victor   VIK TAH

W    Whiskey    WISS KEY
X    X-ray    ECKS RAY

Y    Yankee    YANG KEY
Z    Zulu    ZOO LOO

 

__________________________________________________________________________________________________________

April 18, 2021

“Stump the Chumps Night”

By WB6AMT

 

Good evening to all.

It seems that we are back from the issues with WordPress.

This being a Stump the Chumps night, Anything is up for grabs for a discussion.

I do have few photos of our trip up to Low Potosi yesterday for those interested in what the site looks like and the direction we are going to squirt our RF to the valley area. The site is close to 6,000 ft, hopefully it will serve us well.

Where H2 gets weak down I-15 towards Jean this is going to open up that I-15 corridor as well into Sandy Valley and Goldsprings, and hopefully South towards Stateline.

Can’t wait to do a new coverage test once we are up and running.

This site has internet and security for our equipment as well as video cameras keeping an eye on things, and the BEST part…we can drive right to the building!

 

#1 The site for the H1 and D Star repeater

 

#2 Antenna locations

 

#3 View from the site to the valley

 

#4 Downtown is there…. behind all the haze

 

#5 Lo Potosi Project Engineer scoping things out

 

#6 The new home for the D Star repeater and the new H1 repeater

 

#7 Battery shelves we will be getting.

 

Thats about it, after we get all the equipment installed we’ll be sure to share that at that time.

 

De WB6AMT

 

_______________________________________________________________

April 4.2021

How to use a multimeter

#1  Digital LCD or LED multimeter

Some LCD digital meters have a sensitivity of Megohms per volt, making them very attractive when measuring a high impedence circuit, because it won’t load down the circuit or measurement under test.

images

 

#2 Display driver circuit LED

cb4c3562d9e957dcac7bebb78a9139a6

 

#3  Analog Multimeter 

Quality meter movements sensitivity was 20,000 ohms per volt, which depending on the circuit would change the tuning or measurement by loading the circuit down.

To a circuit it could look like you just connected a 20K resistor in the circuit.

 

images (1)

 

 

#4 The meter movement inside

The DArsonval movement is a DC moving coil-type movement in which an electromagnetic core is suspended between the poles of a permanent magnet. This was first called a galvanometer before the development of the D Arsenval movement. They were the first instruments used to detect and measure small amounts of electric currents.

NV_1017_Mulreany_Figure01

Note…that when using an analog meter the Polarity or Positive and Negative leads MUST be hooked up correctly or the meter movement will deflect the needle in the opposite direction and can damage the movement.

 

#5 What are some of the uses of a typical multimeter?

* DC voltages when checking a battery or power supply output.

* Checking the charging voltage that your car’s alternator produces.

* Checking the AC voltage at an outlet in your home.

* Determining what AC voltages an unmarked transformer is producing.

* Measuring the ohms of a resistor or potentiometer.

* Checking the voice coils of a speaker.

* Checking a fuse or lamp to see if it is open.

* Measuring the current that a circuit is drawing from its power source.

* Measuring the charging current to a battery being charged.

* Use as a continuity checker with an audible tone.

#6 Analog meter face

 AA_Battery_analog

 

#7  Digital meter face fisplay

AA_battery_digital

#7A  What am I seeing?

AA_digital_reverse

 

 

#7B  Measuring a “AA” battery incorrectlyAnalog_switched_leads

 

 

#7C

Power Supply output

 

 

#8 Measuring vehicle alternator output

Vehicle battery

 

 

#9 Measuring Resistance (zero’ing your meter leads)

DSCN1895

 

#9A  Measuring a unknown potentiometer – Meter is set to measure 20KDSCN1896

 

#9B  Close but not as accurate as a digital

Analog5K

 

#9C  Measuring a fixed resistance

!K_resistor

 

 

#10 Measuring current demand

LED current

 

#11 Measuring current with leads reversed

DSCN1902

 

 

#12 Continuity testing (low resistance range)

Used to track a short.

Check for good ground.

For checking fuses that are sand filled. Typically used in high voltage circuits and unable to see the element in the glass tube.

Checking connections or solder joints that look suspicious.

 

Your multimeter is probably the one item in your tool box that will be used more often than any other tool. 

 

The information that it will tell you in just a few seconds will become your goto item.

Make yourself a few different types of leads for your meter with E-Z hook clips, alligator clips and even a large set of clips to connect to a battery terminals.

When Measuring current of a device make sure that the metter leads are large enough gauge wire to handle the current safely.

Always remember to DOUBLE-CHECK the meter settings before connecting to a voltage source.

Meters have a lot of capabilities and it is easy to destroy the meter by not paying attention to what you are working with.

73  WB6AMT

—————————————————————————————————————————————

March 28, 2021

“How to solder…and how NOT to solder Plus making solder repairs”

Thank You Johm KJ7OEN for tonight’s suggested topic.

This will include thru-hole joints, Surface Mounted Devices – SMD, wire splices, How to repair damaged traces or pads, and how to remove excess solder from a joint and correcting a BAD solder connection.

I have found that there are many opinions about soldering as there are folks soldering. The following has proven to work for my style of board assembly.

While working at Southcom International, a company manufacturing military communication equipment under RF Harris, my job was the Manager of the Production Test Dept. I oversaw the testing, alignment and repair of circuit boards being made on the assembly line including making ECN (Engineering Change Notices).

It was also my responsibility to teach an ISO 9000 (at the time) refresher training course to the assembly line workers doing the assemblying of circuit boards going into a military radios SC-106 vehicle comm unit and the SC-130 manpack radio for the United States Marine Corps and United States Army.

There are many requirements in that type pf production soldering, including the correct amount of solder (and NO MORE) due to weight restrictions, when producing a Military radio several thousand solder joints with just a little too much and there is a very real weight difference in the overall unit’s weight, which can lead to board or unit rejection by Quality Assurance dept or the customer. Imagine this condition on satellite circuit board assembly and the weight  specifications needed.

I’m going to touch on what is practical to solder for a ham building or repairing a circuit board today and the tools needed.

-Soldering station with Temperature control (Preferred) and tip assortment

soldering stations

-Dampened sponge to wipe the tip for each connection

-Quality solder (not lead-free) fluxed SN60/40 or similar, applies to Electronic Silver solder also. (See photo #5 below)

-Tip cleaner (helps to protect the tips plating tip cleaner

-Desoldering vacuum device or Desoldering Wick braid.

solder wick

 

Probably the single most important part of soldering is PRACTICE, Make use of the following tips and tricks. Practice pc boards (new) are available for cost of postage. (email me)

I personally recommend a low wattage iron 15-40 watt or a soldering station with a temperature control. This temperature control and proper soldering iron tip becomes very important depending on what your joint will be comprised of parts wise.

#1  Correct means to transfer heat to pad and component leadSolder image

 

#1A Soldering plated thru-holesBoard_design2

#1B Lead sizesSoldering A

 

#2 Soldering TipsTips

 

#3 Soldering large gauge wire (16-10 ga) to a terminal post or lug

IMG_20201129_234941756

Using a large conical tip 700 degrees, .030″ solder allows the heat to transfer quickly to all the wires and to the post to accept solder quickly without damaging the insulation on the wire.

It’s necessary to use the correct size solder for the joint your making because of the amount of rosin core flux that will be released as the solder liquifies for the particular joint.  ( Here I used  63/37 .030″ ).

Too little flux and you will end up holding the tip on the connection too long to get the solder to flow & fill the joint.

I normally use .015″ solder for most of my circuit boards I build. These are 1/8th watt resistors, Integrated circuit pins, 3mm led leads etc.

The reason for .015″ is that all my boards are thru-hole plated and I want the entire thru-hole filled. I want very little solder above the pcb surface so that the component leads can be flush cut to the pc board when finished.

#4 Leads cut close & flush with boardIMG_20210326_122111378

Initial trim to get out of the way of other solder joints, then a final flush cut of all joints.

<Video #1>

#5 .015″ SolderIMG_20210326_133947063

Most of the solder we use on electronic circuits is labeled 60/40, meaning that it has 60% Tin by weight and 40% Lead by weight. 60/40 Sn-Pb, melts at 188 °C (370 °F)

Soldered labeled as 63/37  has slightly different weights and has a lower melting point, typically 183 degree C (361F).

.015″ solder is ok to use by hand on SMD solder connections without leaving too much solder on the connection pad or island.

The preferred method to solder Surface Mounted Devices are to use soldering paste on a cut-out stencil to apply the paste to the pads and a hot-air soldering tool.

#5A Hand applied pasteCU_Hand_Pasted_PCB

#5B Hand placementmaxresdefault

 

#6 Tips and Hot-air noozles

71T07hSSOoL._AC_SL1500_

 

#6A Surface Mount Device soldering by hand prepping

SMD3

#6B Surface Mount Device soldering by handsmd4

By applying a small amount of solder to one of the pads first, then hold the part in place and re-wet the connection with your needle tip to reflow the solder.

If all the pins are aligned correctly, make the next solder connection at the opposite end of the part to hold it in place and straight, while you solder the rest of the pins/pads.

Note- I used less than 1/16″ of .015″ solder for each pin/pad of the SMD Relay.

 

#7 SMD Parts2N2222 SMD

 

#8 Placing part by hand2N2222 SMD

At this time I need to say that it is possible to solder SMD parts by hand on a board like the above.

Is it easy? Not really!   Is it for the faint of heart…probably not.

While trying to do this demo, once the solder was on the pad I tried to place the transistor on the board with my SMD tweezer…..

The first attempt….the transistor completely disappeared by the the time I moved from the bench top to the location highlighted by the Red arrow above. I never felt it leave the tweezers! Have no idea where it went!

The second attempt….the transistor made it to the board surface….but I breathed a sigh of relief and whoosh, it disappeared!

My final attempt (third transistor) was with the help of a piece of scotch tape.….grab the transistor on the mat with the tape, placed it on the board and stuck the tape to the board and soldered it in place to the first pad making sure it was straight. Easey-Peasey!

 

#9 Finally!2n2222

After discovering the tape trick it was no problem getting the rest of the parts installed by hand.

#10 In-line wire splicesIMG_20210326_162008233

#10B  Just enough solder to fill the wiresIMG_20210326_162055542

All ready for a small piece of shrink tubing.

 

Problem Joints

Correcting a bad solder joint or fixing a missing pad or trace is not that hard to do with a little patience and analyzing how to go about the repair.

 

#11 Burn’t trace on a pc boardTrace

 

#11A  Trace jumpertrace fix

This is an excellent use of those resistor leads that get trimmed from your circuit board building projects. Be sure to pre-tin the wire lead with fresh solder

I keep a 35mm film canistor filled with cut-offs over the years, they make good jumpers, the bigger wires like 1/2 watt & 1watt resistor leads can handle more current.  Don’t forget to clean the board of all the burn’t flux as it is corrosive if left on the board.

 

Repairing a missing pad

#12 Missing Pads

IMG_20210328_145815104

Missing pads normally occur when de-soldering single sided circuit board traces that are not thru-hole plated.

The pads or “Donut holes” lift off the board when heat is applied too long on a joint trying to unsolder a connection, and the adhesive bonding between the copper and the circuit material  is compromised.

The repair of a missing donut hole is similar to the burn’t trace repair.

Cleaning a short distance on to clean copper where the pad or trace lifted from, tin the copper with a little solder.

#13 Missing Donut hole fix

images1

Next take a component lead cut-off and form it around the lead coming up thru the hole that is missing the pad, solder in place.

Next bend the lead to match the original trace layout over to the fresh copper you have pre-tinned, trim and solder in place. Make sure that the size of the replacement conductor is adequately sized for the current that the original pad/trace was handling.

#13A Point to point trace replacementf4vew03jm0v7j4x-large-e1537929441900

 

Another Donut hole repair, is to place a piece of copper foil and solder to the component lead and to the fresh copper on the trace itself.

#14 Alternmate Donut hole fix (occupies a lot of space)

images

I’m not a big fan of this type of repair because it normally is too close to surrounding component connections.

I’m sure that there is something that I have left out, so please let me know and we can talk about it.

 

73 DE WB6AMT

_________________________________________________________________________________________________________

 

December 13, 2020 at 8pm  

VSWR

VSWR2

50OHMS

#1

vswr4

#2

vswr5

There is a plethora of equipment available that will assist you with measuring the VSWR of your antenna system. Too many to list here.

A directional watt meter like the Bird Model 43.

#3 Model 43

model43

#4  MFJ-259-C

MFJ259

#5  N1201SA Vector Impedence AnalyzerIMG_20201213_100950121

#6 Checking portable antennasIMG_20201213_101427455

 

#7 Checking feedlines

vswr6

#8 What do we know?

vswr9

#9  What does it all mean?

reflected power

 

#10  Types of transmitter/PA VSWR protection

ACTIVE

#11  Circulators

Circulator

#12  Circulator

Circulators

Final

Obviously a radio system’s VSWR is important for the proper operation of the station and to extend the life of the equipment involved.

Let’s hear from anyone that has had to tackle a high VSWR condition and your results.

Tonight’s audio stream is provided by Dave W3QQQ.

73 DE  WB6AMT

____________________________________________________________________________________________________________

December 6, 2020 at 8pm  

“How to add an “S” meter to your radio, that has a LCD bargraph”

This presentation was originally created for showing at several different radio clubs in the valley. We will be bringing  some of our past favorites for the benefit of all our newest club members and participants to the Tek Net.

Being an avid transmitter hunter, I have over the years used many types of radios, some were great…some not so good. The one thing that was evident was that the radios that had an analog “S” meter was by far easiest to use.

Why add an “S” meter if there is already one on my current radio’s LCD display?

There’s several reasons that an external “S” meter may be desired….

 

The radio may not have an “S” meter or is inadequate or difficult to see.

A good example is if the radio being used, is a commercial radio that is being used in the amateur radio service.

#1 

Maxtrac

In my case, I wanted to be able to see a large meter with ease while driving, during a transmitter hunt.

#2

Picture2

An analog meter will give you a more dynamic visualization of signal change than a stepped or block  bargraph that is on so many of today’s modern radios.

Any change in signal strength level is indicated by the needle swing on the meter instantaneously.

A LCD bargraph increases or decreases the number of blocks on the bargraph in increments (little blocks), that can be misleading when rotating the directional antenna in use is trying to find the “peak” signal direction.

How can we do this?

#3 Picture3

If your radio already has an “S” meter you can add an external one very easily.

It’s a simple matter of disconnecting the internal meter and wire in a meter movement that is the same type, place it up where you can easily view it.

A lot of “S” meters are 1-ma meter movements and are plentiful online and at swap meets real cheap.

If the radio has a bargraph “S” meter, than it is time to obtain some technical data about that radio so that a “S” meter circuit can be built and added.

A manual for most radios can be obtained from https://www.manualslib.com/

You will have to register to use the site (no charge). It is worth the time to do this to be able to download manuals and technical data pertinent to your needs.

This project will involve a Yaesu FT1500M VHF mobile radio.

 

The following approach to adding an external meter is going to be the same no matter what the brand or model of FM receiver is used, even some scanners.

#4  The block diagramBlock Diagram

Block diagram of the receiver will help you identify and locate the IF integrated circuit on the circuit board.

 

#5 Schematic

Picture5

Schematic of receiver shows that Q2023 is the IF Ic where we are going to connect our circuit.

 

#6 

Schematic2

The RX signal leaves the crystal filters XF2001/2002 into the IF amp Q2021, then into the limiter D2021, then out into the IF integrated circuit TA-31136FN at pin number 16.

 

#7 Adding our circuit to the radio

  Picture6

FT1500M main board out of the chassis.

The TA31136 IF integrated circuit is located on the underside of the main board. Soldering these connections onto the Ic’s pin isn’t for the faint of heart, I can lend a hand on this part.

 

#8 Close-up of pin 16

Pin16

#9 “S” meter circuit schematic

Meter schematic

 

#10 Meter driver circuit board

Meter_brd

This circuit is a very basic meter driver circuit.

Depending on the particular radio’s IF level, this will do a good job of having an external “S” meter.

There are some other ways of accomplishing this using an IF subsystem IC with a tuning meter output, similar to the tuning meter on an FM stereo receiver, thats for another day…

 

#11   In the radio where the speaker use to be

Picture10

 

#12 Swap meet specials on meters

Picture12

#13

Picture11

Don’t like the meter face that is on the meter that you have chosen for your project…

CHANGE IT!

Most quality meters can be taken apart or the front lense can be removed, giving access to the meter face.

Carefully remove the two small screws holding the meter face in position behind the meter’s needle.

Carefully remove the face without touching the needle.

#14 

Picture14 Picture23

Make a new meter face on your computer, print it on an adhesive label, and put it on the face….careful to align the face to match the needle location. Practice getting the label the way you want it to look on plain paper first, then print on the adhesive label.

#16 Custom meter face

Picture16

Time to hook it up and test it.

#17    Test #1

Test1

#18    Test #2

Test2

#19    Test #3

Test3

Conclusion…

New “S” meter circuit is displaying a greater dynamic range than the segmented LCD bargraph meter.

Any signal level changes will be easily displayed.

Anyone wanting to build this project, I will supply the components (minus a meter) at no cost. You have to come by my QTH or mail me an envelope with return postage, and I will send the parts to you.

There are many styles, sizes and prices online of 50ua meters to suit your individual taste. I currently have a 6″ 50ua meter we found online in my vehicle to connect to several radios that I use for T-hunting.

This isn’t a real difficult project to build, a total of 8 components, but careful soldering to the radio’s main circuit board is essential.

This is the same circuit I have installed in a Yaesu FT-7800, Yaesu FT-7900, Alinco, Motorola, and now this FT-1500M. (Note)

This method works for other brands and types of radios including scanner receivers.

73 until our next project….

___________________________________________________________________________________________________________

November 29, 2020 at 8pm  

DMR by WB6MIE Tony”

Both of these guys have over four decades each in radio experience. Some in commercial two-way service and implementation of systems as well as being a licensed ham during that time.

Hands-on experience is the best experience ( my opinion), these guys have it.

Get your questions ready because they can answer them and help you get your DMR or P25 radio on the air.

Here is Tony’s entire presentation if you care to download the presentation to refer back to. dmrfinal

Digital Mobile Radio – an overview

Presented over the Henderson Amateur Radio Club Tek Net

By Tony Dinkel, WB6MIE

 DMR stands for “Digital mobile radio”. It is a standard for mobile radio communications that is defined in the European Telecommunications Standards Institute (ETSI) Standard TS 102 361 parts 1–4. You can Google that if you want, but it goes far deeper than the scope of tonight’s presentation. In fact, most publications on this topic delve far deeper than I intend to go tonight, please consider this an overview of the system and some simple rules of entry.

fig1

Figure 1. A simplified diagram of a 2 timeslot DMR conversation in progress.

DMR is a two time slot, Time Division Multiple Access (TDMA) communication system. It was designed to service the commercial mobile radio market, hotels, taxi cabs, trucking companies, private security and other types of “dispatch” applications. Because it is a commercial system, we have to adapt our operations to it by using its existing feature set. Talk Groups, Group Calls, Private Calls, Color Codes and Time Slots are most likely all foreign terms to most hams that are analog users.

About “time slots”… with regular ham radio analog communication we get just a single time slot. A single conversation occupies all of the time on a given channel. With DMR and TDM we get to have two independent conversations on the same RF channel. Two separate QSOs? Yes, two separate QSOs, on the same channel, at the same time, and all within the FCC’s 2013 12.5khz emissions mask. This makes DMR one of the most spectrally efficient voice communication modes on the ham bands today.

Operating under Part 97, we don’t have to meet this emissions mask right now. We can continue occupying our full 25khz bandwidth channels. But this spectral efficiency may become more important to us in the future. I’ll talk a little bit more about this later.

The concept of having two independent conversations going on the same channel at the same time may make some peoples brains hurt. It’s called multiplexing and it goes on all the time in the real world. You are a user of multiplexing systems and you don’t even have to know about it. You use voice multiplex systems every day if you make a phone or cellular call. Whether you know it or not, you conversations are taking place simultaneously with millions of other calls, all being carried on massive multiplex systems.

Or consider an FM stereo radio station. Two audio channels, left and right are broadcast to your stereo multiplex receiver and we don’t even think about it. Well, I think about it a lot because my job is to maintain systems like this, but you as the end user don’t have to think about it at all, it just happens. Listen to a Beatles record on an oldies FM radio station. If you hear “Flying” or “Revolution #9”, you will hear an example of just how independent these two channels can be.

Multiplex systems seem unlimited in scope. In my younger years I worked with Frequency Division Multiplex or FDM. This was a technique where a “baseband” of separately modulated RF carriers was modulated onto a higher frequency RF carrier, around 1 ghz. These systems carried up to 20 independent conversations at the same time.

In later years I was working with a system called T-1, which carried 24 simultaneous conversations using a technique called Time Division Multiplex or TDM.

These systems grew into T-3 systems which carried 28 T-1s or 672 conversations. Then 3 T-3 systems were combined onto a system called Optical Carrier 3 or OC-3 for 2016 conversations, or more specifically “voice circuits”. We really have to refer to these as circuits because each time slot also carries channel associated signaling messages such as on hook, off hook and caller information. Or in the case of ham radio, channel keyed, channel unkeyed, caller identification, and which conversation you wish to participate in.

fig3

Figure 2. Shows a comparison between conventional analog and two time-slot TDMA.

So, to recap, in analog, what you hear on the repeater is our only current talk group. We don’t really refer to it as a talk group because it’s just where we talk, but it can be considered a talk group for the purpose of this discussion. The only equivalent in DMR terms is “ALL CALL” and that is not really meant for two way communication in this context. +In DMR, using different talk groups and time slots, it is possible for a conversation to be going on over a repeater channel and not be able to hear it. That’s not really ham radio you might say. I’ll come back to that and other unique aspects of DMR later. First, lets look at the steps involved in generating a DMR signal.

There are 4 steps involved in generating a Digital Mobile Radio signal. Thankfully, they are all taken care of inside the radio, no additional boxes or computers are needed. This is the last time you should have to think of these steps, I present them here to simply explain the process.

fig2

Figure 3. A basic block diagram of the DMR signal generation process.

  1. Analog to Digital Conversion

When a radio user presses the Push-To-Talk (PTT) button and begins speaking, the voice is received by the radio microphone and converted from an acoustic pressure waveform to an analog electrical waveform. The voice waveform is then sampled by an analog to digital converter. In non two-way radio applications, a 16-bit sample is taken every 8 kHz, this produces a 128,000 bits per second digital bitstream, which contains far too much information to send over a 12.5 kHz or 25 kHz radio channel. Therefore, some form of compression is required.

  1. Vocoder and Forward Error Correction (FEC)

Vocoding, for Voice encoding, compresses speech by breaking it into its most important parts and encoding them with a smaller number of bits. Vocoding compresses the voice bitstream to fit the narrow 6.25 kHz equivalent radio channel. The vocoder used in DMR is an AMBE+2TM which was developed by Digital Voice System, Inc. (DVSI). You can Google that if you are interested.

This particular vocoder works by dividing speech into short segments, 30 milliseconds in length. Each segment of speech is analyzed, and the important parameters such as pitch, level, and frequency content are extracted. These parameters are then encoded using a smaller number of digital bits. Forward Error Correction (FEC) is also applied. FEC is a mathematical technique that enables the receiver to both validate the integrity of a received message and determine which, if any, bits have been corrupted. FEC enables the receiver to correct bit errors that may have occurred due to radio frequency (RF) channel impairments. Think noise, phase distortion, multipath, etc. This effectively rejects noise that can distort an analog signal and by comparison enables more consistent audio performance throughout the coverage area.

This error correction has it limits, it can’t correct for gross errors or total loss of signal. It’s only able to correct for the occasional dropout, so don’t expect a miraculous increase in coverage. It can and does operate quite well at eliminating the noise associated with linear signal to noise degradation experienced when traveling away from a repeater or other station. It can and does work out to just about where you would typically find an analog FM signal to be totally unusable, perhaps just slightly farther. There are also timing related distance limitations imposed by DMR but I don’t know if I have ever reached the actual timing limit.

fig4

Figure 4. A comparison of voice quality in analog vs digital transmission.

  1. Framing

At this stage, the vocoder has compressed the 128,000 bps input signal to 3,600 bps or 3.6 khz. In framing, the vocoded speech is formatted for transmission. This includes organizing the voice and any embedded signaling information, such as color code, group ID, PTT ID, call type, etc. into packets. These packets form a header and payload type of structure with the header containing the call control and ID information, and the payload containing the encoded speech.

This same structure can also relay Internet Protocol (IP) data packets, the IP packets are simply an alternative form of payload to the radio.

The two-slot TDMA implemented in DMR uplinks use a 30ms window for each time slot, this is further divided into a 27.5ms frame and a 2.5ms gap. This means when transmitting, your mobile transmitter is only turned on for 27.5ms every 60ms.

In contrast, the DMR repeater transmits a continuous data stream even if only one timeslot is being used, the 2.5ms uplink gap is replaced with a Common Announcement Channel or CACH burst, that is used for channel management and low speed signaling. The 27.5ms frame consists of a total of 264 bits, a 108 bit payload, 48 bits for sync or embedded signaling, and a second 108 bit payload for a total of 216 bits of payload per frame.

The vocoder must compress 60ms of audio with FEC into 216 bits of data for transmission. The 2.5ms gap is used for guard time to allow PA ramping and propagation delay. Because of propagation delay and synchronization there is a limit to the usable range of DMR. I’ve never worked out what that range limitation is, but I don’t believe I’ve ever reached it. I do believe that the limit is far enough out that it will never affect us in the Las Vegas area.

The header information is repeated periodically throughout the transmission, thereby improving the reliability of the signaling information as well as enabling a receiving radio to join a call that may already be in progress when, for example, it is just turned on or tunes to the channel. This feature is called “late entry”.

 

  1. TDMA Transmission

Finally, the signal is encoded for 4FSK RF transmission. The bits contained in the digital packets are encoded as symbols representing the amplitude and phase of the modulated carrier frequency, amplified, and then transmitted. TDMA organizes a channel into 2 time slots: a given radio’s transmitter is active only for short bursts. By transmitting only on their alternating time slots, two calls can share the same channel at the same time without interfering with one another, thereby doubling spectrum efficiency. Using TDMA, a radio transmits only during its time slot, that is, it transmits a burst of information, waits, then transmits the next burst of information.

Break for questions and radio cool down.

It is important to note that all of this “spectral efficiency”, two time slots, error correction and the other stuff comes with some engineering tradeoffs. When people think of “digital” they think about extremely high quality audio. Nothing about digital mobile radio is high quality. Digital two-way radio was never about high quality voice transmission. It’s about cramming more users in an existing finite amount of bandwidth and selling more radios. Anything that involves compression loses something in the process, by design. Parts of speech that are familiar to us are simply thrown away by the compression algorithms. Speaker recognition, tone, inflections and other nuances are simply lost. All that is transmitted is the important stuff, the speech, with as few accouterments as possible. The reproduced voice can sound almost mechanical at times. And because of the way the digital signal is recovered, there is no noise. So there are no cues for when you are about to lose a signal. It simply drops out. There may be some unintelligible fragments of something that sounds remotely like a human voice, but that’s it, then nothing.

Also, historical problems cannot be solved by digital radio. System issues with coverage and interference are not necessarily eliminated. Adjacent or co-channel interference may sound different to a digital user, but digital technology does not solve interference issues. For example, analog interference will not be heard as voice to a digital radio and vice versa, but disruption of system performance can still occur.

Some historical perspective

Now why is all of this a big deal? Because back in 2008, the FCC decided it was a big deal. Back then commercial users were facing a spectrum crunch. More entities than ever before were using the radio spectrum, and every single one of them were asking for more. Voice users, data users, cellular and broadband companies, television and radio broadcasting all have tremendous bandwidth requirements. The FCC decided that decreasing the bandwidth that we all occupy with our voices would be a great idea.

By January 1, 2013 all voice radio communication systems would occupy no more than 12.5 khz bandwidth for a single voice circuit. Since the radio spectrum is not an infinite resource, we have to try and fit as many users into that limited resource as possible.

That spectrum crunch may have been relieved for a little while, but it never really ended. It is now worse than ever.

As Ham radio operators, we historically have not really ever faced a spectrum crunch. Yes, we have lost spectrum slices here and there. Some of it was for noble causes and some of it was not. But it still  seems that we have plenty of bandwidth. On the hf bands there always seems to be plenty of room to camp out on a frequency and call CQ. And not so much on the 2 meter band but on the UHF band there seems to be plenty of dead space to put repeaters, simplex channels, different forms of data communications and other emissions. These days are about to come to a close. Our usable frequencies are under intense scrutiny in the form of commercial interests that need our frequencies to build their 5G, 6G, 7G and whatever comes next communication systems. Our frequencies are a commodity and they will be traded as such, for big money, with the blessing of the FCC and the rest of the US Federal government. “Alternative” spectrum may be offered, but it very well may not be appropriate for our needs or just not enough.

Eventually, and possibly sooner than we all think, we will need systems like DMR to utilize the meager slices of spectrum that we will be left with.

Applications such as “Trunked Radio” may become popular. Trunking is popular in commercial radio and public safety systems. It involves a set of common radio channels that are shared between a large number of users. A rack of 5 repeaters on only 5 RF channels would give us a total of 10 logical channels. Each user would select the group of users that they want to communicate with and a channel would be assigned to us automatically as everyone else talks around us. Common talkgroups could be assigned so we could have our basic channel that everybody in Las Vegas talks on, kind of like what we have now on the harc network.

The trunking application is called Capacity Plustm in the Motorola lexicon. More specifically, Linked Capacity Plustm would be more correct, since we would be linking our repeaters together over Internet Protocol Site Connecttm or IPSCtm.

Now I will get off of my soapbox and get on with the rest of the show.

But first…

Break for questions and radio cool down.

As I said earlier, DMR has some unique requirements. The first thing you are going to need is a Radio ID number. Go to:

https://www.radioid.net/register#!

and follow the instructions. After you receive your Radio ID number, you need to program it into the radio ID field of your radio codeplug. If you will be using more than one radio at the same time, in the case of a family or spousal unit, you will need more than one radio ID number. Don’t even try to key up on a DMR channel without a proper radio ID number. It’s the same as saying your callsign.

To find your first repeater, either use repeaterbook or just Google Search for DMR repeater (your area). For example, a Google search for DMR repeaters Las Vegas sent me to:

https://lasvegasdmr.com/repeater-list/

I clicked the Potosi UHF link and ended up with a plethora of listings of talkgroups, timeslots and frequencies with the appropriate color codes.

When selecting a talk group, keep in mind they are usually arranged by geographic area. A good place to start would probably be 91 or Worldwide. Other good ones to try would be 31327 for Las Vegas Local. Also try 3132 for Nevada Statewide. Explore, don’t be afraid to try things.

Be sure to use the specified time slots for the various talk groups.

The Color Code also needs to be correct. Color Code takes the place of PL or Digital PL in a DMR system. There are 15 “CC”s so make sure you enter them correctly.

Networking or linking of repeaters is an integrated feature of DMR systems. There are several worldwide and many regional networks setup by individuals who are so inclined. One of the friendliest and easiest to enter I have found is the Brandmeister Network. Visit their Wiki at:

https://wiki.brandmeister.network/index.php/What_is_BrandMeister

Click around and learn about them. They really are an incredible system.

My professional and amateur experience is with the Motorola® MOTOTRBO® product line and only with their XPR® series of professional radios. Some of the features I discussed may differ in functionality or not be available on other brands of DMR equipment.

This paper was sourced from my brain and used the Motorola® publication MOTOTRBOtm System Planner as subject matter reference. The part number for it is 6880309t12. If you are seriously interested in DMR I strongly suggest that you purchase a copy for yourself.

In this paper I have made references to Motorola trademarks, patents or other intellectual property. These references were made for the purpose of technical discussion and no infringement upon the intellectual property rights of Motorola, Inc. was or is intended. All of the graphics used in this paper were copied from the MOTOTRBOtm System Planner publication copyright 2016. These were presented for the purpose of technical discussion and no copyright infringement was or is intended.

That said, DMR is a fun mode so program away and talk to some people. The longer you use it, the better it will sound.

Questions

Tony an be contacted at wb6mie@outlook.com

Tonight’s audio stream is here, recorded by Dave W3QQQ

_____________________________________________________________________________

November 22, 2020 at 8pm  

“Differences between D Star and System Fusion”

We got the following email from a club member this week requesting a special Tek Net :

 I would like to see a TekNet explaining the differences, pros, and cons of DMR, D-Star, All-Star, P25 what I can use them for and what equipment is needed. I’ve heard talk of making a “bridge” between our Analog repeaters and the DMR “gateway?” How would that work, and what equipment would be needed?

WOW…As you can see that is a heck of a large request. We are going to break it down into short talks and a round table style of Q&A can to get this request met.

Tonight Chris NO7E will address the D-Star system, and I will talk about Yaesu’s System Fusion radios and how they differ tonight.

First off, originally these are the only digital modes that were designed for amateur use. DMR and P25 and any other modes were originally designed for commercial applications and when those radios were starting to be used in the amateur bands, so came their functionality.

Dmr will be moderated by Tony WB6MIE and P25 moderated by Kirk NO7BS will be on next Sunday’s Tek Net.

These discussions will be short so that each mode will have time and allow time for questions & answers.

Bridges and Hotspots will be coming in the next few weeks. I have no moderators at this time on those subjects. Anyone wanting to handle either of those please contact me at wb6amt@cox.net.

System Fusion

Understand that System Fusion radios use C4FM modulation to communicate. This Frequency Division Multiple Access ( FDMA) was originally used in the analog AMPS or Advanced Mobile Phone System around the world.

Fusion radios can talk on simplex frequencies, station to station or through a DR-1 or DR-2 Yaesu repeater only using C4FM, however you can’t connect to the internet and use remote nodes or “Rooms” with out the additional Wires-X equipment attached to a radio (like your base station) or a repeater. More on that a little later.

What is C4FM?

System Fusion radios operate in three (3) Digital modes and an (1) Analog mode depending on your preference. Yaesu radios have an Automatic Mode Select (AMS) function that instantly detects the received signal mode. The AMS function eliminates the need to manually switch between communication modes.

V/D Mode (Voice/Data simultaneous communication mode)
The digital voice signal is transmitted in one half of the band width. Simultaneously the other half of the 12.5 kHz band width channel is used for error correction of the voice signal and other data. By incorporating error correction technology, effective error correction codes provide fewer interruptions to conversations. The Clear Voice technology developed for the C4FM FDMA Digital mode provides outstanding sound quality.

Voice FR mode (Voice Full Rate Mode)
This mode uses the full 12.5 kHz bandwidth to transmit digital voice data. The increased amount of voice data permits high quality voice communication, providing superb sound quality of both stations.

Data FR mode (High Speed Data Communication Mode)
This high-speed data communication mode uses the full 12.5 kHz bandwidth for data communication. The transceiver automatically switches to Data FR mode when transmitting snapshot pictures, and can be used to transmit large quantities of data at high speed.

Analog FM mode
Analog FM is effective when weak signal strength causes audio drop out in the digital mode, and enables communication up to the borderline of the noise level. Also the use of established Yaesu low power circuit designs provides greater efficiency than the digital modes.

How does this differ from D Star?

The D star  system uses a 2 level modulation scheme. In regards to the raw signal, a low frequency would represent a “0” while a high frequency would represent a “1”.

This means that for a symbol  transmitted you only get a “1” or “0”, so you get 1 bit per baud. 4800 baud modulation on a Dstar signal  means that our data rate is (1 bit X the baud rate ) = 4800 bits per second or 4800 baud..

Yaesu’s C4FM modulation is more complicated.

Full audio rate of  C4FM is:

 4400bps for voice, 2800bps for voice FEC –, Data Full Rate (DW) supports 7200bps, (no FEC) C4FM Framing Details 5 . Frames max Raw rate: 9600bps Payload after framing: 7200bps AMBE Voice: 100ms voice is compressed to 20ms of data Digit Symbol Frequency Deviation

00 +1 +900hz

01 +3 +2700hz

10 -1 -900hz

11 -3 -2700hz

Instead of just a 1 or 0 being transmitted by a low  and high frequency, C4FM has four possible states.

“00” is the lowest frequency.

“01” is the frequency partway between the lowest and the mid point.

“10” is the frequency between the mid point and the highest.

“11” is the highest frequency.

So during any single baud period, the signal could have any one of four states.

Like Dstar, let’s say the baud rate is 4800 symbols per second, but since each symbol could be one of four bit combinations, 00, 01, 10, 11 we are actually conveying two bits per baud.

This means that at just 4800 baud , our raw data rate is actually twice that of Dstar or 9600 bits per second.

With C4FM we have four possibilities in modulation that in the event of a noisy signal, the receiver is going to have a more difficult time determining if the signal is a 00,01,10,11. This is due to the decreased distance between the four possible states of C4FM as opposed to the 2 states of FSK used in D star.

We all know that the more data we pack in to a smaller period of time , the more bandwidth and power we need to convey it, if we want to maintain the same bit error rate, which is why more work has to be done in the receiver to demodulate the signal for it to work well with weak and noisy signals. This has led to more complex ways to decode the C4FM signals requiring proprietory components and more circuitry for the receiver to be able to reconstruct the audio.

This means that a C4FM signal has a bandwidth approximately 3db wider than a D star signal on the same frequency. Adjacent frequency usage beware.

Wires-X

Wires-x1

Keep mind that the HRI-200 as well as a computer with the following specs has to be purchased and interfaced with a high speed access point internet connection.

OS: Microsoft®Windows®7 / 8.1 / 10
• Clock frequency: 2.0 GHz or more
• HDD: 1 GB of empty space or more
• RAM: 2 GB or more
• USB port: 2.0 (Full-speed)

• Display resolution: 1366 x 768 or more
16-bit high color or more (32-bit true color is recommended)
• LAN port: 100BASE-TX/1000BASE-T
A wired connection is recommended, do not use wifi.

wires-x4wires-x5

Go here for a complete explanation of Wires-X https://www.yaesu.com/jp/en/wires-x/node/index.php

Go here for an Introduction to System Fusion video:   https://www.youtube.com/watch?v=tNjgHUhhMmA&feature=youtu.be

And an understanding why it is called ” SYSTEM CONFUSION “

D Star With Chris NO7E…

 

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November 15, 2020 at 8pm  

“Building and using a XR2206 Function Generator kit”

Probably one of the best bargains you will ever spend $10.00 dollars on a piece of test equipment on.

The XR2206 High Precision Function Generator kit. IMG_20201113_193501427_HDR

As my hearing gets worse and worse, I’m finding myself having issues with some of the Allstar nodes I build when it comes to getting the audio adjusted to sound good.

Different radios have different audio characteristics, and I found that I’m relying on my oscilloscope more for a visual representation of the audio signals I’m dealing with.

One of the features I like is the frequency range, which is from 1Hz to 1 Mhz. Ranges are selected by moving a plug-in jumper to one of five different ranges with the actual  frequency being adjusted by a potentiometer, a course and fine control.

Depending on the output terminal you use will give you a nice sine-wave, square-wave or a triangle-wave.

Power supplied should be from 9-12vdc, so it runs fine on a 9 volt battery.

Actual time to build this kit was 15-20 minutes, your mileage (time) may vary. The board is of good quality and is not crowded like some kits (including some of my own circuit boards…lol).

#1XR2206_7

The kit comes with a laser cut Plexi-glass enclosure

#2 Parts placement XR2206_1

#3  Schematic & hookup

XR2206-1

#4 Layout 

IMG_20201113_200305028

#5 Jumpers

XR2206_8

#6A Square wave

IMG_20201113_210405401

#6B Triangle wave

IMG_20201113_210326887_HDR

#6C  Sine wave

IMG_20201113_210346414

I have used this little generator for testing some small speakers by setting a frequency of 1000 Hz and turn the amplitude all the way up and it drove the speaker pretty good so I could hear it. Connecting this to a microphone input of a transmitter makes adjusting the deviation of an FM transmitter easy. A pair of these will let you adjust your SSB transmitter and linear amplifier for perfect SSB waveform on your station monitor.

The amplitude does vary depending on the output chosen as can be seen in the last three photos. I did not change the amplitude but you can see that the square wave was about 11 volts output, the triangle wave was over 5 volts and the sine wave was about 3.5 volts, these voltages were all Peak-to-Peak.

Keep in mind that this is a single integrated circuit generator, so don’t expect the output conditioning or features of a high priced signal generator, but for $10 bux and less than a half an hour of your time, you’ll have a handy piece of test equipment to add to your shack.

The following is a commercially made, DS345 Function generator that has fantastic frequency resolution, and that is indicated by the price tag.

Tony WB6MIE bought this piece of equipment for frequency measurements of AM broadcast transmitter’s frequencies down to a tenth (.1) of a hertz. ( Ask him how he did it with a signal generator instead of a frequency counter)ds-345full

I originally got the kit from Amazon and it was here in a couple of days. You can get it here: (copy & paste to your browser)

file:///C:/Users/WB6AMT/Pictures/Lysignal%20XR2206%20High%20Precision%20Function%20Signal%20Generator%20DIY%20Kit%20-%20-%20Amazon.com_1.html

Tonight’s audio stream is courtesy of W3QQQ.

73 until next time..

____________________________________________________________________

November 8, 2020 at 8pm  

“Using a Motorola R2660 service monitor to check your transmitter.”

Motorola R2660-2

 

The Communications System Analyzer or service monitor as it is normally called is probably the single most important piece of service equipment a two-way radio technician needs to have at his disposal.

The multimeter and his trusty wattmeter is very important but his service monitor is normally the first piece of test equipment that gets turned on, whenever a radio needs service.

Not only can you measure the accuracy of the transmitted signal’s frequency, but also the level of audio generated from the radio microphone, the level of the sub-audible tone or digital coded squelch signal that is transmitted to operate the repeater’s receiver squelch but can also generate signals for the alignment of the radio receiver and verify that the different sections of the receiver are functioning properly.

We have mentioned many times on the Tek Nets about how to “talk” to the microphone of our transmitters so that we produce a fully deviated 5khz FM signal.

The reason is so that the receiving station can hear you clearly. Even if you are in a noisey environment, like being out at the fringe areas of the repeater or if we have interference as we sometimes do from Nellis AFB occasionally on the input to H2, not having a fully deviated transmitted signal makes it harder to copy your audio out of the noise or interference, and if your audio is low to the same level of the noise, it’s going to be “game over” because you won’t have any recoverable audio to the receiving station.

However if your audio is higher than the noise level or interference you will still be heard.

It’s simple to practice good speaking habits to your transmitter and we will “see” how this looks today using the monitor portion of this service monitor.

We will only be dealing with the transmitter signal today and will cover the receiver, tuning cavities as well as some of the other capabilities a service monitor has on other Tek Nets.

What are some of the things a service monitor can do?

Features:
• RF Signal Generator Frequency Range: 400 kHz to 1 GHz
• Stabilization Time: .1 Second
• 50 MHz Tracking Generator
• Spectrum Analyzer
• Duplex Generator
• Terminated RF Wattmeter
• Programmable Test Memory
• Relative Signal Strength Meter
• RF Scan/RF Counter Function
• Signaling Simulator: Encoder and Decoder
• General Purpose & Modulation Oscilloscope
• AM, FM Signal Generator
• Off-the-Air Sensitive Receiver

#1 Typical R2660 displayMotorola R2660-3

#2 Various controlsMotorola R2660-4

 

#3 Current DisplayDSCN2388

HARC Tek Net Transmitter Deviation Check video  https://youtu.be/bdJGKwI7GXQ

Notice the different sections on the display:

Upper Left side is displaying the monitor frequency with the audio deviation to the right of the transmit frequency. Under that is the display showing how far off frequency I am compared to the dialed in frequency of 449.9250 Mhz.

Lower Left side is showing our audio on the Modulation Scope. The center line is our zero reference and each horizontal line above and below the center represents 2Khz of audio, so the peaks that go over the second line indicate that we are a little over 4 Khz deviation and by looking at the upper display Dev: it is showing that our actual transmitter deviation is 4.48Khz on voice peaks.

The following pdf was sent to me this afternoon and is a great collection of older service monitors from the past. I actually used the first ones that are shown in my early two-way service days.

This presentation is from 2015 and has a bunch of photos of early service monitors and what they did…including my personal Motorola R2660 service monitor that I used for todays video. ( some times I feel SO old!).

2015-11-06_Service_Monitors_KT7G

If you have any questions about service monitors or how to use them send me a message and I will get back to you.  wb6amt@cox.net 

73 until; next time….Earl WB6AMT

——————————————————————–

October 18, 2020

Tonight is “Ask the Pros” night.

The third Sunday of the month is normally our Ask the Pros get together.

This is an open forum format tonight.

Anything and everything Amateur Radio or Electronics is up for grabs tonight.

Have a problem in the shack or with a radio or possible a mode using one of your radios, this is where you can get the answers you need.  

Don’t be bashful and any question is not a dumb question, please join in.

 

 

___________________________________________________________________________

October 11, 2020 at 8pm  

“What story tells how you became a HAM”

There is a reason why you wanted to get a ham radio license, tonight we want to hear from folks about what triggered that desire to become a HAM.

It can be a short description of something that grabbed your attention or a matter of necessity like getting involved with a Search and Rescue group that used amateur frequencies on the there radios.

Many of us had an ELMER enter our lives and their guidance played a part or maybe it was a magazine article that created that spark…let’s hear about it.

My love for radio and electronics started with my getting a Knight-kit Star Roamer shortwave radio kit for Christmas in 1965 at the age of 14.

Tonight we may go over 9pm to allow for everyone to tell their story, if we do run out of time, send me a write up and I will post all of the ones I receive here so everyone can read your stories.

____________________________________________________________________________

October 4, 2020 at 8pm  

“Repairing an Astron 35Amp power supply”

The tips and techniques that will be displayed and talked about tonight, are not the only way to approach troubleshooting a defective power supply. Some technicians use a AC Variac when trouble shooting ac circuits.

AC line voltage circuits can be lethal, exercise safe handling especially when energized. 

The following methods have worked well for me over many years of fixing and building  low current and high current power supplies.

The processes can be used to troubleshoot a 500Mah Radio Shack power supply or an adjustable high-current 165 amp commercial supply and just about anything in between.

#1 Rear view

Rear

 

#2 RS-35 Schematic

rsblk

#3  Basic PS block diagram

Bloks

#4  Blown protective fuses

IMG_20201003_193432002

#4A

IMG_20201003_193457630

#5 Under the hood

Inside

#5AIMG_20200921_201918701

#5B Checking the rectifiers

Bridge

 

#5C  Checks GOOD

IMG_20201003_221534193[1]

#5D  Checks GOOD

IMG_20201003_221555521[1]

#5E   Shorted!

IMG_20201003_221630171[1]

At this point we know what was causing the violent blowing of the fuse.

A direct short on one of the 23 volt 35 amp secondary ac leads!

A replacement pair of bridge rectifiers were ordered from the manufacturer, and installed when they arrived in a few days.

As a sound troubleshooting method, I also removed the four pass transistors from the heatsink on the rear.

Using the ohmmeter I checked the junctions of the Emitter, Base & Collector just like we did with the rectifier diodes in the bridge, to make sure we didn’t have any more hidden problems to be dealt with prior to powering the unit back up.

When installing the new bridges I made sure that the rectifier blocks had a good coat of thermal grease applied, and to the pass transistors mica insulators also.

The most time consuming element of this repair was the disassembly of the chassis, bridges, configuring the new bridges and removing the pass transistors from their sockets on the heatsink .

Actual testing with the meter took a few seconds for each hookup and test.

Troubleshooting a defective power supply  does not have to be too daunting. All power supplies will consist of the basic building blocks. The regulation circuits and the various sections of the regulator circuit is where most of the complexity will be.

There are many hams in the valley that are willing to help you on the phone while your stepping thru some of the steps to isolate where the fault has occurred, or assist in person.

If the part is no longer available from the manufacturer or out of business, NTE makes over 250,000 replacement components that can be obtained online or at some local shops, so the chance of them having a part that will work for you are very good.

After powering up the power supply (with no load applied), always verify that the output voltage is correct for the application and readjust if necessary.

So…instead of buying a new power supply the next time your shack supply dies, take the cover off and use your ohmmeter and try finding the problem and fixing it yourself.

You have nothing to lose, and may end up with a power supply costing a few dollars to fix instead of a replacement costing a few hundred dollars.

Good Luck & 73

____________________________________________________________________________

September 20, 2020 at 8pm  

“ASK THE PROS” Night

The third Sunday of the month brings us one of our favorite topics.

Tonight is the time to bring your comments or questions that you have out in the open so our club members can chime in and help you get solutions to your problems, questions, ideas…anything ham radio.

Everyone participating is what makes ASK THE PROS night as successful as it is.

Vhf/Uhf T-hunt Transmitter project.

Schematic_Transmitter Controller Dual outputs_2020-09-18_12-36-04

__________________________________________________________________________

September 13, 2020 at 8pm  

“Building and using a 70cm directional antenna”

There was discussion at last month’s T hunt/finish point that there was an interest in direction finding a 70cm frequency for the hidden transmitter in the future.

I have started building a Version “2” T-hunt transmitter that will have a 146.565 vhf transmitter and a 1 watt uhf frequency also transmitting at the same time. Both RF outputs will be fed into an antenna combiner so it can be fed to a single dual band antenna like a GP-3.

The initial test frequency will be on the H5 frequency of 449.850 so that most folks that have all the HARC  “H” channels programmed into their radios can T-hunt on H5 frequency without bothering anyone in Pahrump and we will see how that works out

Seems like a great time to start talking about a small uhf directional antenna for your vehicle.

Being a bit lazy, I will start out with an antenna I already have, a 5 element quad antenna that was originally built 6 years ago. It has a fair amount of gain if my memory serves me correctly of about 8-9db forward gain.

We will be building a new quad today for the presentation photos.

#1 Original UHF Homebrew Quad Antenna

IMG_20200913_120952673[1]

 

#2 Materials list

IMG_20200913_121327379_HDR

(2)  48″ Fiberglass driveway markers, 5/16″ dia.   $2.28 ea.

(1)  24″ x 1-1/2″ x 3/4″ Poplar   $2.44

#3 18Ga Copper picture hanging wire

IMG_20200913_130917455

#4 Cutting materials

IMG_20200913_122651465_HDR

You will need four rods cut to 9-1/2″ long and six rods cut to 8-1/2″ long.

Sand a flat spot on each end being careful to keep the rod straight so the ends were flat and inline with the other end.

_

#4A

IMG_20200913_123433382

#4B Drilling the ends

IMG_20200913_125317629

On all rods drill a 1/16″ hole near the end of each rod (1/8″ from end)

On one 9-1/2″ rod drill a second hole, this will be the Driven element.

#5 Element spacing on boom

QuadDimensions1

#5A Element centering prior to gluing

IMG_20200913_135107325

This example is 3-15/16 from the end of the ruler, against the wide side of the boom on both sides. The rod is centered when the rod is sticking out the same distance on each side. This applies for the narrow width side also. Be sure to mark the rod against the boom so you will know where to put the rod when gluing.

When you are ready to apply glue, insert the rod to the mark against the boom, pull the rod out about 1/2″ and apply glue to the rod, spin the rod as you insert it back to your mark and be sure that the drilled holes on the ends are facing up. The holes need to be in the correct position so you can thread the wire through each end of the rods later.

#5B

IMG_20200913_153720021[1]

#6 Prepping the wire

IMG_20200913_162007164

#6A Solder the loop

IMG_20200913_162544380

When threading the copper wire thru each rod, use plenty of pull to get and keep the wire tight and straight until you have it back to the small loop and pull tight….bend….wrap it, trim and solder like Photo 6B.

#6B Creating/ attaching each loop

IMG_20200913_163649287

#6C Creating the feedpoint

IMG_20200913_172056806

As mentioned earlier, the feed point has two holes for each end of the Driven Element’s loop. You will connect the coax shield to one end of the loop and the center conductor to the other end of the loop like 6D.

#6D Coax at feed point

IMG_20200913_181722336

The feedpoint of the quad antenna is actually in the horizontal plane for the antenna to be VERTICAL polarized.

A favorite trick of quad users is to make two feedpoints with two coax cables going to a Two-port antenna switch, this allows the operator to select between Horizontal or Vertical polarization of the receive signal.

This antenna is small enough to use easily at the finish point to SNIFF out the secondary baby transmitter.

73 DE WB6AMT

____________________________________________________________________

September 6, 2020 2020 at 8pm  

“Charging your cell and tablet faster”

This seems like a reasonable question to ask.

After getting a new phone this week requiring a different changer than my old Android used, a little research seemed to be in order. I was made aware that not being just a different charger, but the science behind this new  charging method and the capabilities were nothing less than surprising.

Charging a phone is simultaneously incredibly simple and can be maddeningly complex. Depending on what you are using, how your using it and what you expect or what your trying to achieve.

Basically any USB port in the world can charge any phone, but some will recharge half your battery in the blink of an eye, while others can barely be able to keep up with your phone’s natural battery drain.

If you’re charging your phone on your nightstand overnight, the charger that came in the box with your device will easily get the job done over the course of seven hours.

But if you’re trying to get some extra juice into your device between meetings at work, during a few minutes at the gate before your flight boards, every percentage point you can add to your phone’s battery meter counts.

Luckily, the charging world is finally starting to use a single standard: USB-C Power Delivery, which can communicate with your device to deliver the fastest charging speeds it can handle.

#1

main-qimg-0d5c24fbdadd4b1995648b65c7a0d8e4

Typical connectors on charging cables

WHEN FAST CHARGING MAKES SENSE

The charger you use with your phone overnight doesn’t need to be fast. Fast charging really shines in situations where you only have a few minutes to recharge, but will need your phone to last the rest of the day. If you spend a lot of time traveling, or work in a job that takes you away from your desk, a few minutes of fast charging can be all it takes to keep your device alive for the rest of the day.

It’s also worth noting that most phone manufacturers throttle charging speeds on nearly-full batteries, both for safety and for the lifespan of the battery. For example, once your iPhone reaches 80%, its charging speeds will automatically drop no matter what it’s plugged into. So if you’re hoping to fast-charge your device during your morning commute when your battery is still over 90%, its not going to happen.

iPhones

Most iPhones ship with a tiny, 5 watt charging brick, but for nearly a decade now, Apple’s phones have supported charging speeds of up to 12 watts, which is why you’ve probably noticed that your phone charges faster when plugged into an iPad charger.

But all of the latest and greatest iPhones (starting with the iPhone 8 and iPhone X, from 2017) support even faster charging, up to 18 watts, with a compatible USB-C Power Delivery charger and a USB-C to Lightning cable.

It was found that 18 watt and greater chargers could charge an iPhone battery from 0% to over 50% in just 30 minutes. The included 5W charger, by comparison, barely cleared 25% in the same time period.

Pretty much any USB-C Power Delivery charger will max out your iPhone charging speed, including the latest lineup of small, gallium nitride-powered chargers.

#2

31563-53249-GaN-charger-size-comparison-xl

Conventional and Gallium nitride-powered changer

The 18W Anker PowerPort III Nano is esentially the same size as the charging brick that Apple includes with most iPhones, and is one of the smallest and most travel-friendly options available.

If you only want to bring one charger with you while traveling, RAVPower’s 30W charger includes an 18W USB-C port, plus a 12W USB port that you can use to charge a second device simultaneously.

#3

PC105_1000_720x

#4 USB-C Power Delivery pcb

nikon-mh-25-battery-charger-06

Android

#5Android

Android phones, which are made by a variety of different manufacturers, are understandably a bit more complicated and used the Micro-USB connector prior to the USB Type C Power Delivery change.

#6 

97611

Micro USB on most Android prior to USB Type C Power Delivery

For many years now, most high-end Android phones have supported Qualcomm Quick Charge technology (though some, confusingly, rebrand the technology with their own names). Quick Charge begat the faster Quick Charge 2.0, which begat the even faster Quick Charge 3.0, which has given way to Quick Charge 4.0, which for all intents and purposes is the same thing as USB-C Power Delivery.

Luckily, most modern Android phones support some variety of USB-C Power Delivery just like the iPhone (though, again, many will have a different name for it), but the exact implementation can vary from phone to phone.

For example, Samsung’s Galaxy Note 10 and Note 10+ use non-standard 25W charging profiles that are incompatible with most third party chargers. But with very few exceptions, the same chargers we mentioned earlier for iPhones will also charge your Android device quickly (assuming you have a USB-C to USB-C cable).

There is also a new technology developed called PowerIQ 3.0 technology, which is able to communicate back and forth with almost every major device, and adapt its output to deliver the fastest possible charging speed, whether you’ve plugged in an iPhone, an Android phone, or even a laptop.

#7 Nekteck 45w Car Charger612budrohjL._AC_SL1200_

And if you want to maximize your charging time while you’re driving to and from work, this Nekteck car charger includes a 45W USB-C port that’ll charge everything from your phone to a laptop, plus an additional USB port for a second device.

Battery Packs

If you want to fast-charge your iPhone on the go without a power outlet, many USB battery packs released over the past few years support USB-C Power Delivery charging as well.

The RAVPower 26,800mAh pack features a 30W USB-C port, two other USB ports, and is one of the highest capacity batteries that you can legally take on a plane. Great for long flights or camping trips.

 

NOTE ** When shopping around for a cheaper way to go for your particular needs make sure that it’s MFi-certified, which means it has Apple’s seal of approval, and is guaranteed to be compatible with your iPhone.

For more information on Gallium Nitride chargers and why and how they are going to revolutionize the charger market, click here for  the full download:  Gallium Nitride chargers

73 WB6AMT

____________________________________________________________________________

August 23, 2020 2020 at 8pm  

“Ham Radio…1000 hobbies in 1”

That statement was made by a TV news person describing an interview at a Ham Radio Field day event up at Mt. Charleston in Las Vegas, after talking to over 25 hams.

The one thing about ham radio is that you can dive as deeply as you want into the field of electronics, communications, antennas, digital communications, public service, contest -as competitive operating, solar applications, geophysics sciences, world-wide DX-ing  as it’s called, building robotics using ham radio to communicate with, Test Equipment – Building it and using, Radio Interference, Grounding and many more including just using ham radios as your personal communications tool.

Let’s try to break it down into some categories and then dive into the categories even farther

Software Defined Radio

sdr

Above is Nate’s N8BSD SDR project

OIP

<1MHz to 3000MHz – USB PC SDR dongle cost about $25 

Terrestrial Microwave
– 1 GHz & Up

Microwave Meshhttps://www.arednmesh.org

Weak signal

microwavers
– HF, VHF, Microwave
– Tropospheric ducting

     – Meteor Scatter

     – Plane Scatter

Satellite
– VHF/UHF FM & SSB
– Microwave GEO (QO-100, Es’hail 2)
– ISS (Voice & Packet)

– ATV/DATV (amateur TV)

ATV_Transceiver_User_Interface1

– SSTV ( see below)
– DVB-T/DVB-S
– NTSC Format

hqdefault

Digital Data modes
– CW

– VOIP
– RTTY
PSK31

BAD-PSK31

– FT4 / FT8
– JS8CALL
– WSPR/

WSPR_map1

WSPR – Weak Signal Propagation Radio

JT9/JT65/MSK144
– APRS / Packet Radio
– PACTOR

-WINLINK    https://www.winlink.org/

Winlink-Packet-Session

Send and receive E-mail over HF ham radio

 

Digital voice modes
– DMR
– DSTAR

2820h2

– Allstar Voip

Message_1515617005061[1]

Allstar node for Rasp Pi without a radio 

– P25

– EMCOMM / Skywarn

Ham-radio-amateur-communications-repeater-handheld-frequency-tech-diy-2

A portable GO BOX with radio, tuner, power supply and internal battery

sample-emcomm-winlink-network-l

Contesting
– QRP

SOTA

mountain-641478_960_720

Summit On The Air involves hams taking their radios to the tops of mountains and making contacts to gather points per contact.

– JOTA

Scouts

Jamboree On The Air

Antenna building / radio building / tinkering

DSCN2276

Homebrew T-hunt antenna attenuator made out of printed board material

What about the frequencies?

Starting at the lowest and going higher

VLF below 500 khz

007

Very Low Frequency antenna

 620 meter band

1750 meter band part 15

2200 meter band – This is the lowest frequency a ham can transmit on, 136 KHz.

 

HF 1.7 to 30 mhz

maxresdefault - Copy

From the modest, starting out…..to the

maxresdefault (1) - Copy

Avid Heathkit builder

CW ( Morse code)

Morsecode

SSBsignal-2020-08-23-130600[1]

NO7BS SSB operating station (just out of the picture is his Henry 2K Linear Amp)

 

FM on 10 meters

Cobra_200_GTL_Big

Some CB radios can be modified to operate on 10 Meters

Digital modes, pactor, sitor, amtor, winlink, psk31, ft-8, more

ft8-20m-screen

Sample of FT-8 screen on your computer

SSTV

signal-2020-08-23-131017[1]

Slow Scan Television from NO7BS today

 

DX

DXing is the hobby of receiving and identifying distant radio or television signals, or making two-way radio contact with distant stations in amateur radio or other two-way radio communications. Many DXers also attempt to obtain written verifications of reception or contact, sometimes referred to asQSLs “

 

Contesting

Contesting

By operating on battery power and other qualifiers more points are earned

NR5M_Houston_Texas

NR5M Radio club contest station

VHF 50 mhz to 225 mhz

6 meters magic band

FM

SSB

Meteor scatter

Sporadic E layer skip

SporadicE-NPS

Auroral scatter

Chasing the MUF

MUF propagation prediction is a statistical science. The maximum usable frequency (MUF)is the highest frequency that, with a probability of 50% of the time, can be used for radio communication between two points at a specified distance (but not necessary in all directions) via refraction by the ionosphere.

 

2 meters 144-148 mhz

FM

TRANSMITTER HUNTING

THuntCar

Home made T hunt antenna & mount

SSB

Digital modes, DMR, Fusion, DStar, P-25

Packet radio

APRS

APRS

 

 

UHF 300MHz to 3000Mhz

FM

SSB

Digital modes, Allstar, DMR, Fusion, DStar, P-25

Weak Signal

Digital

Packet radio

APRS

Moon Bounce also called EME

EME

 

Satellite/ISS

Keith-Arrow

 

 

Microwave 

Wideband FM

Narrowband FM

SSB

Weak signal

Propagation modes

Tropospheric scatter

Rain/snow scatter

 

Millimeter wave above 50 ghz

Here is a paper on getting on first 725GHz!

First connection in the 725 GHz amateur band DB6NT 7

This is a vintage Ham Radio film please watch it and see how some of us got going in ham radio with so much enthusiasm.

      https://www.youtube.com/watch?v=5CVnzNNSsdU

We have only scratched the surface….

______________________________________________________________________

August 9, 2020 2020 at 8pm  

“What is the “Cloud”…really?”

To some of you, no explanation is needed.

However this week I received the above question for the third time from three different hams over the past couple of months.

I am going to pretty much use most of my narrative on screen so that it will be available for later lookup. I have a feeling that this will be a Tek Net that will spark interest to others unaware of the HARC TekNet.

We have received positive comments on adding the entire Tek Net audio file of the evenings Tek Net at the end of the session after the net, for those folks that missed the net can listen to it in its entirety at a later time.

For those who don’t know much about me, I’m an old guy (70 years old) and got my ham license 47 years ago and still get referred to as youngster by some of our regular Tek Net members! lol

Having been pretty active in amateur radio for most of that time, I will be the first to admit that I have forgot many things technical or plain don’t know a lot about some technological things.

Modern technology too often uses unclear phrases to describe new technologies whose meanings can be tough to comprehend from their contexts. “Big data,” “internet of things,” and “5G” are a few that come to mind.

However, few are more confusing than “the cloud”, the invisible data storage system that seems to exist in the air/ atmosphere around us, despite being made of very real and physical components.

I’m going to try my best to explain just what “the cloud” is, so the next time one of your neighbors asks you what is it or so you can understand what is meant when you hear a tech person toss the term around.

 

What is the cloud?

The cloud is a metaphor for a global network of remote servers that operates as a single ecosystem, commonly associated with the Internet.

Shane Huston KG7QWH our HARC Tek Net IT Specialist defines the cloud as the following:

The Internet is drawn as a Cloud.  The cloud consists of thousands of Switches interlinked utilizing routing protocols to send your packet to the destination you intended.

What does the cloud do?

#1Servers

At its most basic, the cloud is the umbrella term for the global network of servers that store data. This data can be almost anything. This includes a text document saved to Google Drive, a file shared by colleagues over Dropbox, or a song that an artist makes available through SoundCloud.

The data that make up these files is hosted on large server farms, some of which may be owned by the companies themselves, others of which are rented like Microsoft Asur, Intel Multi Cloud, Digital Ocean, Amazon Lightsail, and many others.

The main appeal of utilizing the cloud instead of saving files on a physical drive or a local network is that once the files are on these systems, they can be accessed from anywhere by anyone. It is this kind of access that allows virtual teams to collaborate around the globe and allows today’s hyper-mobile workforce to engage with projects from remote settings.

How do you get to the cloud?

Even if you don’t realize it, you probably interact with the cloud on a regular basis. Most cloud-based services are designed to be accessible from a simple web browser on a desktop or mobile device.  Many functions we depend on rely on the cloud, such as email services like Yahoo Mail and Gmail.

However, the cloud can be utilized to perform more advanced functions than just this. Cloud servers are high end pieces of technology, and other devices can take advantage of their computing powers.

For example, a popular new piece of technology is Google’s Chromebook, which is a low-cost laptops running on comparatively cheap, low-powered hardware. They are entirely dependent on an internet connection to hook up to cloud-connected apps and services, meaning that you can get high-level functionality out of inexpensive equipment.

#2

samsung-launches-chromebook-plus-pro
Inexpensive Google Chromebook laptop

Cloud storage helps preserve data

#3 Storage

Storing data on the cloud instead of on a hard drive (internal or external) not only makes it easy to reach from anywhere, it helps save local storage space and ensures that file’s safety.

Tools such as Google Photos can be set up to automatically upload photos to cloud storage, meaning that your phone never fills up, you can take as many photos as you want, and if your phone gets damaged, the photos won’t be lost.

Are there any risks with the cloud?

As with any new technology, there are some things that you should be aware of. Since cloud-based data requires an internet connection, if you find yourself without one, you cannot access your data unless you pull a hard copy off before you lose service. In addition, data that exists someplace beyond your phone or desktop is at a slight security risk, so be aware of this when saving sensitive information.

Finally, since the data leaves your physical control when it goes on the cloud, you can’t protect it from being destroyed by some sort of disaster at the server farm.

However, most servers include more back up and safety systems than the average user would have anyway, so this risk is negligible.

So, the next time your coworker sends you a photo to review or a friend shares a song with you, remember, it is all thanks to the collaborative power of the cloud.

 

I hope this answered some of your questions about what is the “cloud”.

The following audio clip was created by Dave AG7ZF so you can enjoy this evening’s narrative of the entire net.

There is some after net discussions too.

73 – Earl

_______________________________________________________________________________________

August 2, 2020 2020 at 8pm  

“Connector Basics – RF connectors 100”

Tonight’s moderator is Tony Dinkel WB6MIE

Tony has over 50 years experience with all types of RF connectors on about as many pieces of electronic and communications equipment. He will be able to answer your questions regarding the different kinds of RF connectors and of course we welcome all comments to the net.

Tony’s presentation photos are located here https://www.facebook.com/104477997564655/photos/pcb.304596007552852/304590967553356/?type=1&theater

The following audio clip was created by Dave AG7ZF so you can enjoy this evening’s narrative of the entire net.

 

An additional download on the new band plan changes allowing Technicians HF frequencies is here:

https://documentcloud.adobe.com/link/review?uri=urn:aaid:scds:US:178a9784-ddc5-4fbc-96f8-2c206d484dfd

73 & see you next week!

_________________________________________________________________________________________

July 29, 2020 2020 at 8pm  

“APEX presentation for HARC’s TAG meeting”

#1

ApexView2_4_19_2019

#1AMountain Range

#2ApexMap1

#3ApexPath2Top

#420180128_143231_Burst01

#520180128_141023

#5AY3u3l7BQ

#620180128_141040

#720180128_141111

#8IMG_4342

 

#8A

img_7583

#9IMG_7584

#10IMG_7634

#11IMG_7625

#12IMG_7629

#13IMG_7621

#14IMG_7616

#15IMG_7589

#16IMG_7592

#17Apex Interior - Feb 01 '19 01_22_02 PM

#1820181230_135139

#1920181230_115232

#2020180720_125057

#20A20181022_162729

#21a2

 

#2220180720_125119_Burst01

#23IMG_7601

#24Message_1545868863620

#25apex_cam3

#2620190112_141625_Film3

#27ek1Ym6HA

The end…73

_________________________________________________________________________________________

July 26, 2020 2020 at 8pm  

“Connectors Basics (or 101)  – Audio types” (and a few others too!)

Continuing in our Connector Basics presentation tonight we’ll be touching on the audio types of connectors used in modern devices and and some of the Do’s and Don’ts when using them in your own projects.

Audio Connectors

Another familiar connector group are those used for audio-visual applications–RCA, phono and phone type. While these can’t truly be considered to be of the same family, as the various USB connectors are, we’ll consider both of them to be in the same vein while discussing them as audio connectors.

You’ll probably immediately recognize the 1/8″ version of this connector as a the plug on the end of a pair of headphones. These connectors actually come in three common sizes: 1/4″ (6.35mm), 1/8″ (3.5mm), and 2.5mm. ¼” size connectors find a lot of use in the professional audio and music

“Phone” Type Connectors

#1     1/8″ or 3.5mm phone plug

 Phone type

Headphone-type TRS phone plug, 1/8″. Typically, tip and ring will carry the stereo audio signals while sleeve will be connected to ground.

Often times the 1/4″ phone plug is called a professional or music industry instrument connector or an older stereo headphone plug.

Most electric guitars and amplifiers have 1/4″ tip-sleeve (TS) jacks on them. Some home entertainment center stereo amplifiers still have a 1/4″ headphone jack on the front panel.

The most common headphone plug on newer equipment is the “Mini” phone plug which is 1/8″ (3.5mm) tip-ring-sleeve (TRS) is very common as the connector for headphones or audio output signals on MP3 players, cell phones or computers input and output connections.

A least common plug is the “Micro” phone connector, I have seen these become more scarce on more audio equipment but they are still in use.

Some ham radio handhelds provide a 2.5mm tip-ring-ring-sleeve (TRRS) jack for connecting to headphones that also include a microphone for hands-free communications. There are lots of combinations being used on most of the Chinese and Japanese import HT radios for the headphone and external microphone connection.

The common availability of these connectors and cables makes them a good candidate for general purpose connectivity applications–for instance, long before USB, Texas Instruments graphing calculators used a 2.5mm TRS connector for a serial programming connector.

The lack of shielding makes them poor candidates for high-speed data, but low speed serial data can be passed through these connectors easily.

It should be remembered that tip-sleeve connector types are not designed for carrying power; during insertion, the tip and the sleeve can be momentarily shorted together, which will do damage to the power supply.

 

#2     1/8″ Mono phone plugphone plug

1/8″ phone plug. Note the lack of a ring contact on this connector.

#3     1/8″ Stereo Jackphone jack

                   1/8″ printed circuit board mount headphone jack 

With corresponding pin connections labeled. When no jack is inserted, an internal switch connects the tip and ring pins to the adjacent unmarked pins, allowing insertion detection.

 

#4   4-circuit Specialty plug4circuit plug

This 4 pole plug is what your cell phone has installed so that a headset with a microphone can be used. This plug has also been found to be in some home audio/video equipment for the Left and Right audio as well as the video signal.

#4A  Tip-Ring-Ring-Sleeve plug

549278bd87526f8516b729cd62c896e5

RCA Connectors

Familiar as the home-stereo connector of choice for many decades, the RCA connector was introduced in the 1940s by RCA for home phonographs. It is slowly being supplanted by connections like HDMI in the audio-visual realm, but the ubiquity of the connectors and cables makes it a good candidate for home-built systems. It will be a long time before it is obsolete.

Female RCA connectors are usually found on devices, although it is possible to find extension or conversion cables with female jacks on them. Most RCA connectors are connected to one of four types of signals: component video (PAL or NTSC, depending on where the equipment was sold), composite video, stereo audio, or S/PDIF audio.

 

#5 RCA Phono

phono

Female RCA connector, for video signals. Typically, NTSC or PAL video signal connectors will be yellow.

Left & Right audio phono jacks and plugs are typically colored Red & White.

Male RCA connectors are usually found on cables.

#6 RCA Phono Cables

rca1

Male RCA plugs. Red and white are usually for audio applications, with red denoting the “right” audio channel.

Some consumer RCA cables will have a third wire ( Yellow) that is a bit larger than the Red & White wire, this is a Video cable and is typically a 75 ohm wire.

Power Connectors

While many connectors carry power in addition to data, some connectors are used specifically to provide power connections to consumer devices. These vary widely by application and size, but we will only focus on some of the most common ones here.

Barrel Connectors

Barrel connectors are typically found on low-cost consumer electronics which can be plugged into wall power via bulky AC wall adaptors.

Wall adaptors are widely available, in a variety of power ratings and voltages, making barrel connectors a common means for connecting power to small projects.

The female barrel connector, or “jack”, can be purchased in several varieties: PCB mounted (surface mount or through hole), cable mount, or panel mount. Some of these connectors will have an additional contact that allows the application to detect whether a power supply is plugged into the barrel jack or not, thus allowing the device to bypass batteries and save battery life when running on external power.

#7 DC & AC Barrel connector

barrel plug

Unattached male barrel plug, for attachment to any power supply. Note that the sleeve connection is designed to be crimped onto the wire for extra strain relief.

The male barrel connector, or “plug”, is usually only found in a wire termination.

Barrel connectors provide only two connections, frequently referred to as “pin” or “tip” and “sleeve”.

When ordering, there are three differentiating characteristics of a barrel connection- inner diameter (the diameter of the pin inside the jack), outer diameter (the diameter of the sleeve on the outside of the plug), and polarity (whether the sleeve voltage is higher or lower than the tip voltage).

Sleeve diameter is most commonly either 5.5mm or 3.5mm.

Pin diameter is contingent upon sleeve diameter; a 5.5mm sleeve will have either a 2.5mm or 2.1mm pin. Unfortunately, this means that a plug designed for a 2.5mm pin will fit in a 2.1mm jack, but that the connection will be, at best, intermittent. 3.5mm sleeve plugs usually mate to a jack with a 1.3mm pin.

#8 DC & AC Barrel Jack

barrel jack

CAUTION!

There are varying opinions on the gender of the jack and plug for these low power coax connectors.

Depending on where your get these connectors, the jack can be referred to “male” barrel connector due to the pin in the center and vice versa for the plug. Make sure to check out the product image and specs to find what you are looking for! In the above illustration the Insertion Detect pin is a connection that makes contact to the shield ( normally ground) when there is no plug inserted and opens that connection when a plug is inserted.

This is used in battery applications to disconnect the internal battery when external power is applied to the device.

Polarity

Polarity is the final aspect to consider; most often, the sleeve will be considered 0V and the tip will be a positive voltage relative to the sleeve.

Many devices will have a small diagram indicating the polarity expected by the device; care should be taken to adhere to this, as an improper power supply may damage the device.

 

#9 Polarity diagram

Polarity

Common polarity diagrams for AC adaptors with barrel plugs. Positive polarity (tip positive, sleeve 0V) is most common.

The polarity diagram above can often be found at the connector jack of your equipment or on the serial number sticker such as on the bottom of a laptop computer.

This tells you the polarity of the instrument and is handy when you are making your own power cable. You will normally see this diagram on the wall transformer also telling you what is on the end of the plug.

Plugs of both sleeve sizes are usually 9.5mm long, but longer and shorter ones do exist.

Some products use a negative 5.5mm sleeve and a positive 2.1mm pin; we recommend sticking to that standard where possible, as it seems to be the most common flavor found in the wild.

MOLEX CONNECTORS

#10 MOLEX Connectors

molex

Male Molex connector. The gender of the pins inside the connector is what signifies the gender of the connector as a whole.

Most computer hard drives, optical drives, and other internal peripherals get power through what is typically called a “Molex” connector. To be more accurate, it’s a Molex series 8981 connector–Molex is actually the name of the company which initially designed this connector back in the 1950s–but common usage has denuded that fact somewhat.

Molex connectors are designed to carry a lot of current: up to 11A per pin. For projects where a lot of power may be needed–a CNC machine, for instance, or a 3D printer- a very common method for powering the project is to use a desktop PC power supply and connecting the various system circuits through Molex connectors.

The Molex connector is one where the male/female terminology is a bit odd. The female connector is usually found on the end of a cable, and it slips inside of a plastic shell which surrounds the male pins on the male connector. Usually, the connectors are press-fit only, and very, very tight–they are intended to be connected and disconnected only a few times and, as such, are a bad choice for systems where connections will frequently be changed.

#11 MOLEX Cable connectors

th

MOLEX plugs and jacks are outfitted with some sort of indexing or locating capability, that allows the plug to be inserted one way only, sort of a polarity measure. (notice the corners missing on this hard-drive power cable connector)

Molex connectors can come in a variety of number of connections to meet your applications.

#12    Multiple pin Molex connectors

12pin molex

IEC Connector

IEC connector usually refers to the power supply inlet which is commonly seen on desktop PC power supplies, electronic test equipment and other devices reguiring a three conductor (grounded) power cord.

Strictly speaking, that’s an IEC 60320-1 C13 (female) and C14 (male) connector.

#13 IEC 

iec2

C14 male IEC power inlet, on a DC project power supply. Note that, as with the Molex connector, the gender of the connector is defined by the pins within the hood.

#14 IEC Cable

iec1

C13 female IEC power connector, on a fairly standard AC power supply cable. Cables with this end can be found all around the world, usually with the dominant local AC connector at the other end.

IEC connectors are used almost exclusively for AC power input. The nice thing about using one on a project is that IEC-to-wall cables are extremely common and available everywhere.

Well folks this went longer than I had anticipated, but this is all stuff that can come in handy when information is needed in the future and you will know where to go to find it!

Did you want to review a piece of information mentioned in the narrative, you can find it in the following audio file of tonights Tek Net. 

The following audio clip was created by Dave AG7ZF so you can enjoy this evening’s narrative of the entire net.

                     73 until next week!

______________________________________________________________________________________

July 19, 2020 2020 at 8pm  

“ASK THE PROS” Night

This is our open forum type net, and always comes up with some interesting discussions.

Remember anything Ham Radio is fair game.

Did you want to review a piece of information mentioned in the narrative, you can find it in the following audio file of tonights Tek Net. 

The following audio clip was created by Dave AG7ZF, enjoy this evening’s narrative of the entire net.

_________________________________________________________________________________________

July 12, 2020 2020 at 8pm  

“Connector Basics”

This evening’s topic was suggested by one of our regular Tek Net participants.

This will be a refresher for some and new material for others, however by having all this data about connectors and the wiring to such in one location will provide a really easy access point for future connector references.

Introduction

Connectors are used to join subsections of circuits together. Usually, a connector is used where it may be desirable to disconnect the subsections at some future time: power inputs, peripheral connections, or boards which may need to be replaced.

I’m going to touch on the following and expect that many members tonight have experience with connectors. so join in.

  • Basic connector terminology

  • Categorize connectors into distinguishable categories

  • Talk about the differences between connectors within those categories.

  • Show how to identify polarized connectors

  • Talk about which connectors are best suited for certain applications

 

Connector Terminology

Gender – The gender of a connector refers to whether it plugs in or is plugged into and is typically male or female, respectively (kids, ask your parents for a more thorough explanation). Unfortunately, there are cases where a connector may be referred to as “male” when it would appear to be female; in the examples section, we’ll point a few of those out as we discuss individual component types and explain why that’s the case.

#1

gender

Male (left) and female 2.0mm PH series JST connectors. In this case, gender is determined by the individual conductor.

#2

Polarity – Most connectors can only be connected in one orientation. This trait is called polarity, and connectors which have some means to prevent them being connected wrong are said to be polarized, or sometimes keyed.

Polarity

A polarized North American wall plug. By having two different widths for the plug blades, the plug will only go into the outlet one way.

#3

Contact – Contacts are the business portion of the connector. They are the metal parts which touch each other, forming an electrical connection. This is also where problems occur: the contacts can become soiled or oxidized, or the springiness required to hold the contacts together may fade with time.

contacts

#4

Pitch – Many connectors consist of an array of contacts in a repeated pattern. The pitch of the connector is the distance from the center of one contact to the center of the next. This is important, because there are many families of contacts which look very similar but may differ in pitch, making it difficult to know that you are purchasing the right mating connector.