Next HARC TEK NET will be…..
May 2, 2021
“Starlink Satellite Internet Service”
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Sessions in ORANGE means that that session has been archived and you simply need to click on the ORANGE date/session to go directly to that Tek Net.
The HARC Tek Net will be on all of the normally linked HARC repeaters and affiliates.
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 repeater
What does it take to have a successful repeater
Building your own antennas
Ham swap meets, do you go?
What do you think of the audio on most repeater
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
ARCHIVED TEK NETS
Click on any ORANGE archived Tek Net to go directly to that session, I will get them all archived as soon as I can.
Aug 18, 2019 – How does Allstar work-NO7BS, WB6MIE, WB6AMT
Aug 25, 2019 – How to use a multimeter- WB6AMT
Sept 1, 2019 – General questions/ answer session & Swap meet listings
Sept 8, 2019 – Building a UHF disguise base antenna-WB6AMT
September 15, 2019 – Ask The Pros, KG7QWH, NO7BS, WB6MIE, NO7E, WB6AMT
Sept 22, 2019 – What does the Touch-tone buttons on your HT do?- WB6AMT
Sept 29, 2019 – Mounting mobile antennas for better performance- Motorola Data
Oct 6, 2019 – Remote HF Antenna switch project- WB6AMT
October 13, 2019 Remote Antenna Project Conclusion- WB6AMT
October 20,2020 – Ask The Pros, KG7QWH, NO7BS, WB6MIE, NO7E, WB6AMT
October 27, 2019 – Make an Allstar node in a old radio chassis- WB6AMT
Nov 3, 2019 – Why should I turn my radio on other than for nets- WB6MIE
Nov 10, 2019 – Ask The Pros, KG7QWH, NO7BS, WB6MIE, NO7E, WB6AMT
November 17, 2019 – D-Star In’s & Out’s – NO7E
November 24, 2019 – Follow-up with D-Star from last week- NO7E
December 1, 2019 – Grounding concerns- WB6MIE & NO7BS
December 8, 2019 – Winter Field Day
December 15, 2019 – 18650 Lithium ion battery- WB6AMT
December 29, 2019 – LED’s & How to use them- WB6AMT
Jan 5, 2020 – Capacitor, ESR testing and recapping equipment- NO7BS
January 19, 2020 – 5G Setvice…what is it really- WB6AMT/ NO7BS
February 2, 2020 – Analog vs Digital Radio Performance- W0SKY
February 9, 2020 – How my signal gets to the repeater – WB6MIE
February 16,2020 – Ask the Pros “Your first Ham Radio Field Day”
February 23, 2020 – Grounding from Motorola Manual R56- WB6AMT
March 1, 2020 – Radio Mobile Online Antenna plotting software- WB6MIE/ WB6AMT
March 8, 2020 – DC Power Distribution in vehicles- WB6AMT
March 15, 2020 – Ask The Pros/ LV ARES RODEO- N7ZEV
March 22, 2020 – Introduction yo Software Defined Radios- N8BSD
March 29, 2020 – How COVID-19 has impacted ham radio-
April 5, 2020 – The FCC’s online testing
April 12, 2020 – Build a radio with NiceRF SA-818 HT module- WB6AMT
April 19, 2020 – Ask the Pros night
April 26, 2020 – Open forum…anything goes tonight- WB6AMT
May 3, 2020 – IT-101 Basic Home IT networking essentials – KG7QWH
May 10, 2020 – Building the Searcher Directional Antenna – WB6AMT
May 17, 2020 – ASK THE PROS Night
May 24, 2020 – “Using commercial radios on ham bands” – WB6AMT
May 31, 2020 – “What do you want from a Radio Club?” – WB6AMT
June 7, 2020 – “Surface Mount Devices soldering technologies – N8BSD
June 21, 2020 – “ASK THE PROS” Night
June 28, 2020 – Field Day at the H5 location.
July 5, 2020 – “Adding an analog “S” meter to a radio”
July 12, 2020 – “Connector Basics” Part 1 – WB6AMT
July 19, 2020 – “ASK THE PROS” Night
July 26, 2020 – “Connector Basics Part 2 – WB6AMT
July 29, 2020 – Apex Presentation for the TAG meeting.
August 2, 2020 – RF Connectors 100 – WB6MIE
August 9, 2020 – What is the cloud – WB6AMT
September 13, 2020 – Building and using a 70cm Directional antenna – WB6AMT
January 17, 2021 – Ask the Pros – Open forum discussion
March 7, 2010 – What happened to Ham Radio Central? – 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.
All in one box
Operating after acquired satellite
April 25, 2021
“Using phonetics on VHF/UHF repeaters”
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”
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.
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.
#2 Display driver circuit LED
#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.
#4 The meter movement inside
The D‘Arsonval 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.
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
#7 Digital meter face fisplay
#7A What am I seeing?
#7B Measuring a “AA” battery incorrectly
#8 Measuring vehicle alternator output
#9 Measuring Resistance (zero’ing your meter leads)
#9A Measuring a unknown potentiometer – Meter is set to measure 20K
#9B Close but not as accurate as a digital
#9C Measuring a fixed resistance
#10 Measuring current demand
#11 Measuring current with leads reversed
#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.
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
-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
-Desoldering vacuum device or Desoldering Wick braid.
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 lead
#1A Soldering plated thru-holes
#1B Lead sizes
#2 Soldering Tips
#3 Soldering large gauge wire (16-10 ga) to a terminal post or lug
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 board
Initial trim to get out of the way of other solder joints, then a final flush cut of all joints.
#5 .015″ Solder
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 paste
#5B Hand placement
#6 Tips and Hot-air noozles
#6A Surface Mount Device soldering by hand prepping
#6B Surface Mount Device soldering by hand
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 Parts
#8 Placing part by hand
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!
After discovering the tape trick it was no problem getting the rest of the parts installed by hand.
#10 In-line wire splices
#10B Just enough solder to fill the wires
All ready for a small piece of shrink tubing.
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 board
#11A Trace jumper
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
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
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 replacement
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)
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
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
#5 N1201SA Vector Impedence Analyzer
#6 Checking portable antennas
#7 Checking feedlines
#8 What do we know?
#9 What does it all mean?
#10 Types of transmitter/PA VSWR protection
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.
In my case, I wanted to be able to see a large meter with ease while driving, during a transmitter hunt.
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?
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 diagram
Block diagram of the receiver will help you identify and locate the IF integrated circuit on the circuit board.
Schematic of receiver shows that Q2023 is the IF Ic where we are going to connect our circuit.
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
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
#9 “S” meter circuit schematic
#10 Meter driver circuit board
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
#12 Swap meet specials on meters
Don’t like the meter face that is on the meter that you have chosen for your project…
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.
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
Time to hook it up and test it.
#17 Test #1
#18 Test #2
#19 Test #3
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.
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.
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.
Figure 3. A basic block diagram of the DMR signal generation process.
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.
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.
Figure 4. A comparison of voice quality in analog vs digital transmission.
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”.
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.
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:
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:
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:
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.
Tony an be contacted at email@example.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 firstname.lastname@example.org.
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.
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.
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…
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.
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).
The kit comes with a laser cut Plexi-glass enclosure
#2 Parts placement
#3 Schematic & hookup
#6A Square wave
#6B Triangle wave
#6C Sine wave
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)
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)
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.”
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?
• 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 display
#2 Various controls
#3 Current Display
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!).
If you have any questions about service monitors or how to use them send me a message and I will get back to you. email@example.com
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
#2 RS-35 Schematic
#3 Basic PS block diagram
#4 Blown protective fuses
#5 Under the hood
#5B Checking the rectifiers
#5C Checks GOOD
#5D Checks GOOD
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.
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
#2 Materials list
(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
#4 Cutting materials
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.
#4B Drilling the ends
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
#5A Element centering prior to gluing
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.
#6 Prepping the wire
#6A Solder the loop
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
#6C Creating the feedpoint
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
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.
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.
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.
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.
#4 USB-C Power Delivery pcb
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.
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 Charger
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.
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
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
Above is Nate’s N8BSD SDR project
<1MHz to 3000MHz – USB PC SDR dongle cost about $25
– Terrestrial Microwave
– 1 GHz & Up
– Microwave Mesh– https://www.arednmesh.org
– Weak signal
– HF, VHF, Microwave
– Tropospheric ducting
– Meteor Scatter
– Plane Scatter
– VHF/UHF FM & SSB
– Microwave GEO (QO-100, Es’hail 2)
– ISS (Voice & Packet)
– ATV/DATV (amateur TV)
– SSTV ( see below)
– NTSC Format
– Digital Data modes
– FT4 / FT8
WSPR – Weak Signal Propagation Radio
– APRS / Packet Radio
Send and receive E-mail over HF ham radio
– Digital voice modes
– Allstar Voip
Allstar node for Rasp Pi without a radio
– EMCOMM / Skywarn
A portable GO BOX with radio, tuner, power supply and internal battery
Summit On The Air involves hams taking their radios to the tops of mountains and making contacts to gather points per contact.
Jamboree On The Air
– Antenna building / radio building / tinkering
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
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
From the modest, starting out…..to the
Avid Heathkit builder
CW ( Morse code)
NO7BS SSB operating station (just out of the picture is his Henry 2K Linear Amp)
FM on 10 meters
Some CB radios can be modified to operate on 10 Meters
Digital modes, pactor, sitor, amtor, winlink, psk31, ft-8, more
Sample of FT-8 screen on your computer
Slow Scan Television from NO7BS today
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 as ” QSLs “
By operating on battery power and other qualifiers more points are earned
NR5M Radio club contest station
VHF 50 mhz to 225 mhz
6 meters magic band
Sporadic E layer skip
Chasing the MUF
2 meters 144-148 mhz
Home made T hunt antenna & mount
Digital modes, DMR, Fusion, DStar, P-25
UHF 300MHz to 3000Mhz
Digital modes, Allstar, DMR, Fusion, DStar, P-25
Moon Bounce also called EME
Millimeter wave above 50 ghz
Here is a paper on getting on first 725GHz!
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.
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?
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.
Cloud storage helps preserve data
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:
73 & see you next week!
July 29, 2020 2020 at 8pm
“APEX presentation for HARC’s TAG meeting”
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.
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
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 plug
1/8″ phone plug. Note the lack of a ring contact on this connector.
#3 1/8″ Stereo 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 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
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
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
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.
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 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
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
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 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
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.
#10 MOLEX Connectors
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
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
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.
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
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
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.
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
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.
Male (left) and female 2.0mm PH series JST connectors. In this case, gender is determined by the individual conductor.
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.
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.
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.
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.
The pitch of the pins on the headers on a standard Arduino is .1″.
Mating cycles – Connectors have a finite life, and connecting and disconnecting them is what wears them out. Datasheets usually present that information in terms of mating cycles, and it varies widely from one technology to another. A USB connector may have a lifetime in the thousands or tens of thousands of cycles, while a board-to-board connector designed for use inside of consumer electronics may be limited to tens of cycles. It’s important that you select a connector with a suitable life for the application.
Mount – This one has the potential for being confusing. The term “mount” can refer to several things: how the connector is mounted in use (panel mount, free-hanging, board mount), what the angle of the connector is relative to its attachment (straight or right-angle), or how it is mechanically attached (solder tab, surface mount, through hole).
Here are three examples of the same connector
Strain relief – When a connector mounts to a board or cable, the electrical connections tend to be somewhat fragile. It is typical to provide some kind of strain relief to transfer any forces acting on that connector to a more mechanically sound object than the fragile electrical connections. Again, there will be some good examples of this later on.
This 1/8″ headphone jack comes with a strain relief “boot” slid over the cable to prevent forces on the cable from being transmitted directly to the electrical joints.
USB connectors come in two flavors: host and peripheral. In the USB standard, there is a difference between the two, and the connectors on cables and devices reflect this. However, all USB connectors will have some things in common:
Polarization– A USB connector can only nominally be inserted one way. It may be possible to force a connector in wrong, but that will result in damage to the device.
Four contacts– All USB connectors have at least four contacts (although some may have five, and USB 3.0+ connectors have even more). These are for power, ground, and two data lines (D+ and D-). USB connectors are designed to transmit 5V, up to 500mA.
Shielding– USB connectors are shielded, such that a metal shell which is not part of the electrical circuit is provided. This is important to keep the signal intact in environments with a lot of electrical “noise”.
Robust power connection– It’s important for the power pins to make connection before the data lines, to avoid trying to power the device over the data lines. All USB connectors are designed with this in mind.
Molded strain relief– All USB cables have plastic overmolding at the connector to prevent strain on the cable that could potentially damage the electrical connections.
A USB extension cable, with some of the common features of USB connectors labeled.
USB-A female is the standard “host” connector type. This is found on computers, hubs, or any device intended to have peripherals plugged into it. It is also possible to find extension cables with a female A connector and a male A connector on the other end. (illustrated above)
Female USB-A ports on the side of a laptop. The blue connector is USB 3.0 compliant.
USB-A male is the standard “peripheral” connector type. Most USB cables will have one end terminating in a USB-A male connector, and many devices (such as keyboards and mice) will have a built-in cable terminated with a USB-A male connector. It’s also possible to find USB-A male connectors that are board mountable, for devices like USB memory sticks.
Two types of Male USB-A connectors, on a cable and an stick development board.
USB-B female is a standard for peripheral devices. It’s bulky, but robust, so in applications where size is not an issue, it’s the preferred means for providing a removable connector for USB connectivity. It is usually a through-hole board mount connector, for maximum reliability, but there are panel-mount options for it as well.
Arduino boards, including this Uno, have long used the female USB-B connector, due to its low cost and durability.
USB-B male is almost exclusively found at the end of a cable. USB-B cables are ubiquitous and inexpensive, which also contributes to the popularity of the USB-B connection.
USB-B male connector on the end of a SparkFun Cerberus cable.
The USB-Mini connection was the first standard attempt to reduce the size of the USB connector for smaller devices. USB-Mini female is typically found on smaller peripherals (MP3 players, older cellphones, small external hard drives), and is usually a surface mount connector, trading robustness for size. USB-Mini is slowly being phased out in favor of the USB-Micro connector
USB-Mini female connector
USB-Mini male is another cable-only connector. As with USB-B, it’s extremely common, and cables can be found almost anywhere usually on electronic device power supply chargers.
USB-Micro female is found on many newer peripherals, such as digital cameras and MP3 players. The adoption of USB-micro as a standard charge port for all new cellular phones and tablet computers means that chargers and data cables are becoming increasingly common, and USB-Micro is likely to supplant USB-Mini in the coming years as the small-factor USB connector of choice.
USB-Micro female connector
USB-Micro male is also a cable-only connector. There are generally two types of cables with USB-Micro male ends: one for connecting a device with a USB-Micro port as a peripheral to a USB host device and one for adapting the USB-Micro female port to a USB-A female port, to be used in USB-OTG capable devices.
USB 3.0 micro-B cables look similar to USB 2.0 micro-B connectors but they include additional pins for two differential pairs and a ground. This cable is often times seen on external storage devices.
USB 3.1 C Cable
USB C packs 24 pins into the USB connector. Unlike the previous versions predecessors, this version is reversable! The design of the USB C cable also allows for current above 500mA for your power hungry devices.
Heads up! Depending on the cable, not all of the pins are broken out for USB C.
Some cables may be limited to the USB 2.0 specification with 4 pins as opposed to the full USB 3.1 specification. The reversible USB A to C cables and SuzyQable are a few examples.
Depending on the USB port that is used, you may also be limited in the amount of current that can be provided to your device.
This is it for tonight’s connector Basics.
We will continue on Audio/Visual and other types of connectors on the next segment of Connector Basics in 2 weeks.
July 5, 2020 2020 at 8pm
“Adding an analog “S” meter to a radio with digital display.”
Tonight we will see how easy it is to add an analog meter to a radio that has a digital bargraph “S” meter, no meter at all.
The circuit is a 1 transistor circuit and is made on a 3/4″ X 3/4″ piece of circuit board material. It connects to a point in the radio where the IF signal is present ( Frank will explain).
#1 “S” Meter Original
#2 “S” Meter Circuit N2DKI
#3 HTX212 with meter board
#4 Board tap point connection
#5 HTX212 Schematic
#6 C47 Schematic point
#7 Tap Point C47
#8 Meter box inside
#9 Calibration potentiometer close-up
#10 Meter face
#12 Speaker Top
#13 Dashboard View
You can see how the analog meter has good dynamic range, displaying less than half-scale on the meter while the digital bargraph is still displaying full-scale.
If you have any additional questions or comments for Frank, he can be contacted at firstname.lastname@example.org.
Anyone needing the parts to build this circuit can pick them up from Earl WB6AMT at his QTH in North Las Vegas.
This is a great addition to your transmitter hunting set of “Tools”, so come on out and have more fun from your ham radio.
June 28, 2020
Field Day at the H5 location.
This year we were fortunate to be invited to the H5 repeater location to set up and operate from the QTH of WB6MIE Tony Dinkel.
Not having any HF antennas available, we had to do some setting up.
A new 8′ ground rod at the base of the HyGain AV-18VS antenna was one of the first things to enjoy doing.
A four sided grounding ring was silver soldered together, made from 2″ copper strap creating the connection point for the planned ground radials.
The Tuner was an SGC-230 Autotuner located out at the antenna base and was powered by a 12 volt gel-cel battery for the duration of the weekend as this was a temporary setup with the autotuner.
The 2,500ft roll of 14ga copper ground wire was Georgia Copper, and made silver soldering the radials to the grounding ring easy.
Ground radials were strung out to marker stakes and pulled tight. We started with four runs of over 100 feet each, and will have many more at varying lengths.
1-1/2″ Copper strap was used for the ground and the antenna connection leads.
As can be seen at the base of the vertical antenna, the base connection and loading coil with the taps for the different bands was left off of the construction of the vertical. The vertical is directly connected to the tuner’s antenna input with a copper strap.
The antenna is in the middle of the backyard of WB6MIE’s qth.
The only drawback I found with this antenna location was that the 120ft piece of feed line was short to get to the house, necessitating the addition of another piece of coax to reach the coax pigtail entering the house.
We were using 1/2″ Andrews heliax as well as a quality RG-213 coax. We were forced to use inline coupling.
The H5 repeater antenna support is 10ft piece of IMC pipe and is clamped to a railroad tie with six 2″ pipe clamps with lag bolts. There is an additional 8′ ground rod at the base of the pipe. There is a 75 ft piece of Andrews 1/2″ Superflex Heliax to the repeater.
#9 The H5 8-bay Andrews DB-408 antenna. The antenna is oriented so that the major lobes of the antenna concentrate the energy North and South onto state highway #160.
#10 The operating position
#11 Our logging software was WA0H MicroLog
Can’t wait until next year!
June 21, 2020 at 8pm
“ASK THE PROS”
Every third Sunday of the month is our round table open forum “ASK the PROS” night.
Anything and everything is fair game so long as it is about communications …electronics….homebrew or ham radio in general.
June 14, 2020 at 8pm
“Repeater 100, Overview of Repeater Basics.”
Our guest moderator this evening is Tony Dinkel WB6MIE
What is a repeater?
To start off with, here is a typical place that you want to put a repeater. On top of a nice hill with a clear view and a fast drop in terrain to your desired coverage area. This…
Go here for Tony’s presentation.
Look for you next week!
June 7, 2020 at 8pm
“Introduction to Surface Mount Devices soldering technologies”
Guest moderator tonight is Nate N8BSD
Please click on the link below to follow along with Nate’s discussion this evening.
Nate will pause after each slide to field any questions or comments, so speak up and don’t miss your chance to have your questions answered.
Here are the videos that Nate was talking about…enjoy
This audio clip was created by Dave AG7ZF so you can listen to everyone’s participation of the entire net.
This will be a regular feature in the future….TNX Dave
As always this Tek Net will be archived so you may refer back and watch this slide show or the videos after the Tek Net as many times as you like.
May 31, 2020 at 8pm
“What do you want to see from a Ham Radio Club”
With all the changes that Ham Radio Clubs have been experiencing, I thought that it’s about time I find out what some of the annoyances are….what do you like about how clubs are now and what is something you would like see in the future.
Participate and speak your mind tonight…..
May 24, 2020 at 8pm
“Using commercial 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.
QUALITY (Construction, parts)
ANALOG & DMR
CREATABLE ZONES TO MANAGE THE 1000 CHANNELS
LACK OF MANUFACTURERS SUPPORT
LACK OF ACCESSORIES
LIMITED NUMBER OF CHANNELS
LACK OF SERVICE PEOPLE
ON ONE BAND ONLY (THERE IS AN EXCEPTION)
NUMBER OF CHANNELS
USES CRYTALS ( CURRENT PRICE $100 MIN.)
A little background…
#1 Older radios on ebay
MaxTrac (typical age – 35+ yrs old, typical price $20.00)
#2 XPR6550 (Very popular among hams)
#4 Mobile Chargers & other Accessories
#5 What $100 will get you. (your brand may vary)
Quality components- (drop test)
Performance- (drop test)
Service ability- (after drop test)
#6 Spurious emissions ( typical especially after drop test)
#7 Spurious emissions (commercial radio after drop)
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!
AND STILL GET THE JOB DONE!
May 17, 2020 at 8pm
“ASK THE PROS” Night
NO7BS, KG7QWH, WB6MIE, N8BSD and check-ins….
May 10, 2020 at 8pm
“Building the Searcher Directional T-Hunt antenna kit”
After having such a successful transmitter hunt yesterday, it was apparent that folks enjoyed getting out on a T-hunt…
Today I will review and build a Rainbow Kits SDF-1 “Searcher” antenna kit.
It has become a popular kit that a few locals use to “Sniff” the transmitter’s signal at the finish point.
When your so close to the transmitter that the signal level is so high that the receiver seems to be overloaded and a directional antenna can’t provide a directional bearing, this little 24″ dual dipole antenna really shines.
It doesn’t rely on signal strength to determine direction but rather the phase of the signal reaching the ends of the antennas.
If the signal coming into each antenna is out of phase you hear the audio tone superimposed on the modulation. Out of phase is when the ends of the antenna is not 90 degrees to the radio transmitter.
Since the antenna are phase dependent you will get a “NULL” at two points, these points are exactly 180 degrees apart.
With the antenna held in a vertical manner away from your body and rotated, the adjustable tone that the unit superimposes on the received signal will go into a null as the two antennas are brought to the same distance from the transmitter you are direction finding. At this point the antennas are equal distances from the transmitter in two directions. By moving 15 – 20 feet off to the side you can now get a new directional bearing ( remembering your first direction and crossing your new direction or triangulate the transmitter’s location) and tell you which way you need to go.
Let’s get started…
#1 SDF-1 The Searcher by Rainbow Kits
#2 What’s included in the kit
#3 Clear and concise instructions
#4 Ten minutes later…
#5 Prepping antenna cables
#6 Getting it all together
After soldering the leads from the circuit board to the BNC connector, potentiometer and the on/off switch install a fresh 9 volt battery.
After going thru the check out procedure in the instructions, then it’s on to the operation part of the instruction manual.
My personal opinion of this kit is that you can spend a lot more money for a sniffer type antenna but you won’t get as much bang for your buck as you will from this kit.
On a scale of 1 to 5, it gets a solid 5.
Note– Some heavy duty Velco holding the radio to the Searcher case makes the job a little easier, utilizing a pair of headphones was the icing on the cake for this old guy with bad hearing.
Tonight’s kit is for sale for $60, call or text me at 702-372-9891
These kits are available from http://www.rainbowkits.com or from myself at the monthly Las Vegas Ham Radio Swap meet when I have them in stock.
May 3, 2020 at 8pm
“IT-101” Information Technology 101
Basic IT home networking essentials
with an emphasis for using with Allstar
About KG7QWH Shane Huston…
Shane is a retired Air Force NCO, has formal Information Technology training and has also retired from operating a successful IT service company serving the Las Vegas area.
He is a Microsoft Certified Systems Engineer and brings a wealth of computer knowledge to the Tek Net today.
Shane welcomes your questions and comments, his mission is to assist us over some of these hurdles that can be extremely nerve racking (at least for me!).
Tonight is not the night to just sit back and listen….get those computer questions answered this evening in a clear and concise manner.
Here is Shane’s narrative, is suggested that you print this document out and follow along or refer back to it after tonight’s Tek Net.
KG7QWH Shane has been an active participant on the HARC’s Tek Net since it began 10 months ago and is one of our regular “PROS” on Ask The Pros Night.
Shane frequents the HARC repeater network’s H2 & H3 repeaters.
You can send your questions to Shane at: AGERanger10@gmail.com
April 26, 2020 at 8pm
“Open Forum Night, anything goes!”
Lets talk about whatever is on anyone’s mind.
Antennas or antenna builds…
DYI projects your doing…
“Q” signals for the COVID-19 Times
QLD – I am Locked down.
QUA – I am quarantined.
QPD – I am in a pandemic.
QTP – I have toilet paper, want to trade for a car?
QFC – I am flattening the curve.
QHG – I need a hug.
QSH – I am sheltering in place.
QHS – I have hand sanitizer, Want to trade for a car?
QSD – I am observing social distancing.
QVC – I hate Coronovirus.
Borrowed from the Fair Lawn (NJ) Amateur Radio Club April 2020
April 19, 2020 at 8pm
” ASK THE PROS”
This being the third weekend of the month, tonight is the regularly scheduled “STUMP THE CHUMPS” night.
This is your opportunity to ask those questions that you think our regular “Experts” may stumble on or may not be able to answer.
April 12, 2020 at 8pm
“Building a radio using the NiceRF SA-818 Walkie-talkie module”
#1 NiceRF.com Analog & DMR modules
#1B Where to get these components
#2A SA-818 VHF/UHF Walkie-talkie module
#2B Technical Data
#3A EasyEDA Schematic/ PCB software
#3B Radio schematic
#5A Original breadboard version of the radio
#5B (back) point to point wiring method
#6A Laying out the printed circuit board
#6B How the finished unit looks
#7A Bare boards delivered 3-4 days later
#7B SA-818 and parts installed
#7C Assembly instructions
#7E Solder fillets
#8A Programming with the SU-108 program module
#8B Select #9 “Start Bash Shell Interface”
#8C At the prompt enter < 818-prog >
#9A Radio installed into the project
#9B Allstar node in Maxtrac chassis
#9C Radio to Interconnect board
#10A Interconnect board wiring
Printed circuit board kits are available from WB6AMT@cox.net, Paypal invoice will be sent back to you for payment, items are mailed that day.
SA-818 Carrier board parts kit – $12.00 each (minus SA-818 module)
VOIP Interconnect board parts kit – $12.00 each (Plus shipping)
AR4 4Amp Adjustable Regulator parts kit – $15.00 each (Plus shipping)
April 5, 2020 at 8pm
“FCC testing online”
KJ7NNU Joe is our guest tonight.
Press release on his testing session….
Enter the above in to your browser and read how Joe took his test for his Technician license from the comfort of his home.
March 29, 2020 at 8pm
“How the COVID-19 has impacted Ham Radio” is tonight’s topic.
This will be an open forum style net.
Let’s hear how it has effected you and your ability to enjoy ham radio.
Staying home has this been the opportunity you needed to get on HF a little more.
Have you decided that now would be a good time to start a new project…possibly build a new circuit?
I have a treat for anyone starting a new build and needing components…..
March 22, 2020 at 8pm
“Introduction to Software Defined Radios” will be tonight’s topic.
N8BSD Nate has put together a very informative presentation for everyone to follow along here.
Click on the above to start his presentation. To make a slide larger click on that image, then click on it to return back to the presentation.
He has a lot of photos and information to share tonight.
Take lots of notes and have your questions ready.
You can send your questions or comments directly to Nate at <email@example.com>
March 15, 2020 at 8pm
“ASK THE PROS” will be tonight’s topic.
DAYTON HAMVENTION and the
TRW SWAPMEET in Long Beach is cancelled until further notice.
Yesterday was the Fourth Annual ARES/Races 2020 Ham Radio Rodeo.
The event was hosted at the QTH of Frank N7ZEV and his wife Linda KC7IIT
This event puts a few Las Vegas ARES/RACES ham radio operators on display with their emergency preparedness vehicle setups.
A few of the vehicles
Various antennas in use
Handheld Frequency & Deviation Clinic was available
March 8, 2020 at 8pm
“DC Power Distribution” will be tonight’s topic.
People that do two-way radio mobile installations often times have a personal set of ideas or techniques that were taught to them or developed over time from installing mobile radios into many different locations in vehicles. and solving the problems encountered.
Attention to your vehicle’s electrical system capability is needed so that you don’t over tax the vehicle’s charging system.
Up grading to a premium battery will keep from causing headaches down the road.
If you are running a 100 watt HF rig, you should have a larger battery and upgrade your alternator to keep the battery up while transmitting and so that your antenna will see that 100 watts the radio is producing.
Typical mobile installation
All wiring that is done in a vehicle has to have proper fuse protection as close to the battery or positive power distribution point to break the path in case of a excessive current demand or damage to power leads causing contact to chassis metal.
#1A High Current Protection
#1B High Current car stereo amp fuses
#2A Proper Vehicle Grounding/ Bonding
For maximum performance from the radio and to also insure that your DC power system will have a minimum of ignition/ alternator noise. This cuts down on the possibility of non-bonded surfaces from creating rectification noise where moving metal surfaces touch during movement or vibration. This can occur during receiving or transmitting.
#3A Power Distribution Points #8Ga feed
#3B Anderson Power Poles makes it easy.
#3C HD Barrier strip distribution point
#3D ANDERSON POWER POLE FUSED OUTPUTS
#4 BATTERY CONNECTIONS – Engine area
#4B Trunk area installation
Dual 55Amp Gel-cel installation, piece of acrylic plastic snaps over the connection bar.
#4C Cable management
Use rubber covered metal clamps when managing cable routes.
The following is for entertainment purposes only.
The scarey part is that someone actually thought that what they did in these installations were acceptable!
#5 DON’T EVER DO THIS…
Hope everyone enjoyed tonight’s topic. 73
March 1, 2020 at 8pm
Using “Radio Mobile Online” Antenna Plotting software
Tonight’s moderator is Tony Dinkel WB6MIE on the uses of and how to take full advantage of this antenna propagation plotting tool.
Radio Mobile authored by VE2DBE.
This program is available for free and with only a few limitations frequency wise has the ability to plot paths between two locations and with the appropriate data input will display a wealth of information allowing you to optimize your repeater site’s performance.
This is also being used by many of the Las Vegas Mesh Node sites.
To download the software follow this link:
The installation instructions are very well documented and is easy to follow.
There is also a Yahoo users group that has a plethora of information on this program and is a great place for the exchange of ideas, tips, help and support from other users.
There is also an excellent Radio Mobile Online tutorial located here http://pizon.org/rmw/
This site also has several other RF tools, formula calculators used for designing radio links.
Antenna Downtilt Angle
Downtilt Coverage Radius
System Operating Margin
Watts to dBm
#1 5.8GHz path from Apex to WB6AMT QTH
#3 Coverage plot of H1 repeater from Seven Hills
#4 Coverage are display of the C1 repeater on Pleasants Pk in Ca.
Any questions about this program or if you need clarification on using it can be sent to Tony’s email: firstname.lastname@example.org
or to my email: email@example.com
See you next week!
February 23, 2020 at 8pm
Ground systems from the R56 manual
Motorola’s Standards and Guidelines for Communications Sites R56 Manual has been the go to handbook for those designing, building and maintaining a commercial communications site.
Our discussion this evening will talk about an issue that has occurred on the Henderson Amateur Radio Club’s Apex site.
That being a 60Hz hum that can be heard when a signal is no longer being received and for the duration that the transmitter is still transmitting (Squelch tail duration).
Ground Loop Hum is caused by a difference in electrical potential at grounding points. … When you have more than one piece of equipment in your system connected to a common ground through different paths at different ground potential, like different outlets on the same circuit, you can get a ground loop.
The following link will allow you to download and save The Motorola Standards and Guidelines for Communications Site Manual to your local computer, so that everyone can follow along and be on the same page (literally).
Some of what we will touch on is:
-Common Grounding ( Earthing) page 4-5
There shall only be one grounding electrode system. This include the AC power system ground, communications tower ground, lightening protection system ground, telephone system ground, exposed structural building steel, under ground metallic piping that enters the facility and any other ground system shall all be bonded together to form a single grounding electrode system.
Besides the ground elements shown above there could also be:
Fence grounding conductors
Tower guy wire ground conductors
Radial ground conductors
The main purpose of the grounding electrodes in the earth are to maintain the electrical equipment at the same potential as the earth.
The UL approved ground rod shall be constructed of copper-clad steel, solid copper, hot-dipped galvanized steel or stainless steel.
Stainless steel ground rods shall be formed of an austenitic stainless steel of the 18% chromium, 8 % nickel type.
According to code, the upper end of the ground rod shall be buried to a minimum depth of 24″ below the surface of earth.
Electrolytic Ground systems
Grounding conductor shall be a minimum of #2AWG unless it is a lightening prone area or a military installation and it shall be a minimum of #1/0 AWG.
This conductor may be stranded , however the recommended stranded conductor shall be tinned.
Solid, bare, tinned, copper conductors should be used to minimize the galvanic corrosion between other parts of the grounding electrode system.
Open discussion about Apex.
February 16, 2020
ASK THE PRO’S night.
There is going to be a little recap on some of last weeks discussion on “How my signal gets to the repeater”.
As we were closing the Tek Net last week there were a few issues that were left out of the discussion.
WB6MIE Tony Dinkel will attempt to be on the net tonight from out of town to answer your follow-up questions.
Earl WB6AMT will ask “When was your first time participating at a Field Day event”.
What did you find unique about that experience?
What will your next field day setup be like?
February 9, 2020 at 8pm
How does my signal get to the repeater?
This evenings guest speaker is:
Tony Dinkel WB6MIE.
Tony has over 4 decades of experience in the commercial communications field and will bed able to answer all your questions on tonight’s topic.
It travels through the air…right? But there are always other factors in radio signal propagation. The best path from a transmitter to a receiver is always an “optical” path. That is, if you can see the receiver antenna, you have the best chance having an acceptable signal into the receiver.
Here is a good example of an optical path to our Apex H2 repeater:
I picked a location very near to apex and I had to model 50 meter high antennas to get this path profile
By the way, this is propagation modeling software producing what is called a “path profile”. You are looking at a side view of the path from Apex Peak to the Amazon Tropical distribution center parking lot in North Las Vegas. This is a slice of the atmosphere and the earth terrain elevation directly below the center of the path. This type of plot is not commonly associated with repeaters. Repeater people usually work with a “coverage map”, a type of plot which predicts the signal amplitude that you can usually expect over a large geographic area.
The following is a coverage plot of the H1 repeater from Seven Hills in Henderson.
I use point to point path profiles to understand why my signal sounds good or so bad from a specific location. Also, this type of plot is much better for understanding the concepts that I’m trying to explain.
From a professional standpoint, when we need to construct a radio communication circuit, radio system engineers will use tools like this as a “design” aid. Engineers build systems that need to work 24/7/366. Once the system is built with a particular purpose in mind, it has to work. It can’t fade in and out over the course of a day, week or year. This is referred to as five nines of reliability. That means that our systems have to be available with very few unavailable seconds every day, every year, for the life of the system. Some systems I have installed have been up for over 30 years with no outage time, at least related to propagation anomalies. As hams, we are usually working with walkie talkies. When we push the tx button on our walkie talkies, we are taking a chance that the location we are at can “see” our receiver site and that we can communicate acceptably.
If our signal levels are not acceptable, we need to understand why and be able to make changes to communicate reliably, especially if the location we are transmitting from is important to us, such as our home or base station location.
I typically work with microwave radios for my communication circuits. These employ much higher frequencies, wider bandwidth and complex modulation waveforms. This changes the physics a little bit but the basic concepts remain the same.
I also use very directional antennas that focus the radio signals in fairly tight patterns that are aimed at my endpoints, so very little signal is wasted.
Your walkie talkie does not typically use a directional antenna, it uses an omni-directional antenna. So you most likely waste about 99% of your signal energy that never gets to the repeater.
But what if it does somehow get to the repeater by a reflection? This is referred to as “multi-path” propagation and is most likely the primary mode for ham radio communication in the Las Vegas valley. But what is bad for a point to point microwave circuit is not necessarily bad for ham radio.
In the real world, we can’t always have an optical propagation path. Just from traveling through space, an RF signal loses power. This is partially due to attenuation from the atmosphere itself and the distance that it has to travel. Obstructions, such as the walls of a house or building can cause signal loss too. Mountains and earth curvature can also play a roll in attenuation
Here is a typical multipath propagation plot from H2 to Shane Huston’s house in Henderson:
From this plot you can see that Shane’s direct path to H2 is completely blocked by terrain. Does this mean that he cannot to talk to H2? Not really, I have talked to him at his home through H2 many times. His signal either gets diffracted over the terrain, diffracted around the obstructions or reflected across the valley, probably a combination of all of these modes. Would this path work for a digital microwave system as shown? Absolutely no.
Thankfully, narrowband FM ham radio can take advantage of these anomalous propagation modes.
Now I’ve used several technical words here and I feel like I need to elaborate a little. Attenuation simply means a reduction of something, in this case, a reduction in the power of your signal getting to the repeater. There are some other technical words I’ve used in this paper such as “amplitude”. Amplitude is simply the absolute value of something at an instant in time. For the purpose of this paper, amplitude will refer to values of your signal power in transit to the repeater. Then there is “phase”. Phase is kind of a complex concept but I will try to explain it as best I can. It comes into play when you do not have a perfect optical path to the repeater antenna. If you have an obstructed path to the repeater, diffraction or reflections can cause a mirror image of your signal to arrive at the repeater antenna together with your direct signal. This can often be more than one multipathed signal and their relative amplitudes and phase relationships determine if the signals add or subtract. Think of phase as related to time delay. If one of your signals takes a detour because of a reflection from a large building, it takes a longer path to the repeater antenna. This means that it also takes a longer time for the reflected signal to get to the antenna. If any of you remember the ghosting effect that you would see on old analog television pictures, that was caused by a reflected signal and the direct signal arriving at your TV antenna slightly out of phase or time. A mirror image would be offset and appear as a ghost image in the tv picture.
This is the effect of multipath propagation.
Now that I have mentioned the repeater antenna, this is what it looks like:
The repeater antenna is an eight element or eight bay antenna. All eight of these elements are combined into a coaxial phasing harness that maintains the phase relationship to a high level of accuracy so that a signal arriving in phase at all eight elements is properly summed into one coax and fed to the receiver. The signal from your walkie talkie has to hit all eight of these dipole elements with equal phase and amplitude to be properly repeated.
In narrowband FM voice transmission, as opposed to old school analog tv, there is no picture to offset but the effect is similar. Delayed signals can cause distortion in your voice modulation or they can vary your received signal amplitude as received at the repeater. It can appear that your signal is weaker or stronger than it should be. If the signals arrive at pretty much the same amplitude but are exactly 180° out of phase, your signal will cancel out and you will not be heard. This is why when you move your hand held radio around inside your house, you will notice peaks and nulls in your received signal. You are actively varying the amplitude and phase of multiple copies of the signal arriving at your receive antenna. You instinctively move your radio around to get the best signal. And hopefully, the place where you have optimal receive signal from the repeater is also where you will be able to place optimal signal into the repeater antenna. Unfortunately, the reflections and diffractions that occur on your transmit path are not always the same as on your receive path. You may also notice that your hot spots and cold spots tend to move around in your house. This is because of many factors some of which are, atmospheric density varies, water vapor content changes and this all affects the refraction index of the air your signal has to travel through.
73 DE WB6MIE
February 2, 2020 at 8pm
Analog vs Digital Radio Performance
Tonight’s guest speaker is Skyler W0SKY.
Skyler has created a video showing the real life performance differences between the different digital and analog radios while traveling over the same route.
The agenda will be as follows;
Introduction to Skyler W0SKY
Everyone click on the link and watch his video. https://www.youtube.com/watch?v=KzwB3RcT2KE
Open up our discussion for questions or comments addressed to Skyler.
Tek Net wrap up.
January 19, 2020 at 8pm
5G Service…what is it really
Last minute notes from CES 2020 has introduced some newer information on 5G devices and service. Thanks to Lawrence N6YFN.
We have all heard the hype about how 5G is going to be the best service yet, 100 times faster…. Well maybe.
Every day you hear commercials about how one mobile carrier is faster or has better coverage than the others.
They throw around terms like 4G, LTE, and 5G and expect people to know what they are.
As far as the average person is concerned, five is higher than four, so it must be better — right? Maybe.
Tonight’s Tek Net will be your guide to how a basic wireless networks operate and some of what we can expect from 5G.
If a deeper understanding is wanted, researching any of the terms will give a more in-depth explanation than what we cover tonight in one hour.
TERMS & DEFINITIONS
CDMA – Code-division multiple access is a channel access method used by various radio communication technologies to allow multiple access at the same time.
TDMA (time division multiple access) is a technology used in digital cellular telephone communication that divides each cellular channel into three time slots in order to increase the amount of data that can be carried.
FDMA – (Frequency division multiple access) allows multiple users to send data through a single communication channel , such as a coaxial cable or microwave beam, by dividing the bandwidth of the channel into separate non-overlapping frequency sub-channels and allocating each sub-channel to a separate user.
MIMO – Multiple Inputs/ Multiple Outputs for data handling ( both Cellular and Wifi service) 2X,4X, 4X4
MU-MIMO – (Multi User Multiple Input, Multiple Output)
NFV – Network Function Virtualization ( prerequisite for network slicing )
mMTC – (Massive Machine Type Communications) IoT applications
Mesh WIFI – ( Private systems at first )
5G ACIA – Alliance for Connected Industries and Automation (5G ACIA) Industrial & factory usage.
MNO – Mobile Network Operator ( Typically a mobile network services, cellular provider)
MNOS – Is a Unix-like OS developed in the Soviet Union. It was derived from Unix Version 6 and consequently heavily modified to incorporate many features of BSD Unix.
256QAM – Quadrature Amplitude Modulation 802.11 Wi-Fi standard ( conveys two 90-degere out of phase analog message signals, or two digital bit streams)
Video Optimization – delivery rate for streaming video, which causes the video to be delivered in lower resolutions and to use less data and speed up network speeds for data users.
NB IoT – Narrow-band IoT, a communication standard for IoT devices to operate via carrier networks, using existing GSM carrier wave, in an unused “guard band” between LTE channels, or independently.
PAN – Personal Area Network (Confined), IEEE wireless personal area network standard 802.15.3c, the 802.11ad Wi-Fi standard and 802.11ay standard all specify the 60 GHz band.
At their most basic, wireless networks work in the same way as any telephone or radio that’s been around for a hundred years.
Information is processed, encoded into a radio signal, and sent to another receiver. The receiver decodes the signal and does the whole process over again.
Some of these transmissions are one-way, like the radio in your car, or like your television set that receives signals OTA (Over The Air) or Weather alerts to you cell, but most networks transmit information back and forth.
Instead of calling and receiving like a phone, wireless networks use data downloading and uploading.
When you click on the Facebook app on your phone, your phone receives (or downloads) the encoded information from the Facebook server using radio waves, and decodes it so that the display on your phone can see what your friend ate for dinner last night. When you want to send her the filtered picture you took of that dinner, your phone encodes the photo into digital information so that your cell (radio) is able to transmit those radio waves (or uploads) it to the Facebook server for decoding and posting.
3G, 4G, LTE and 5G are all just ways to make that process faster and process more data in less time.
The electromagnetic spectrum is the highway over which wireless operates, with multiple lanes capable of carrying traffic at different speeds. Higher frequencies – and thus shorter wavelengths – are able to move more information per unit of time.
An easy-to-understand example of this is a basic walkie-talkie. Changing the channel on a walkie-talkie changes the radio frequency at which it operates. You and your friend need to be talking on the same frequency to hear each other. People at other frequencies aren’t going to hear you. The busier the frequency (Frequency congestion or channel loading), the harder it’s going to be for you and your friend to communicate. It’s the same for mobile networks.
What does “G” stand for?
When looking at 3G, 4G, and 5G, the “G” stands for the generation of technology. For example, 5G will be the fifth generation of wireless network technology. Each generation has set standards.
Currently, to be considered a true 4G network, connection speeds need to be at least 100 megabits per second (Mbps) at their peak. For reference, 25Mbps is needed for peak video streaming.
When these standards were announced, 100Mbps speeds were unheard of, which made some wireless companies nervous. They were making strides in technology but couldn’t advertise them truthfully yet.
That’s where LTE comes in.
LTE is in line with the phrase “sort of.” It stands for “long-term evolution” and is used to describe technology that’s attempting to reach the 4G standard. If your phone displayed a 4G LTE symbol, you didn’t have true 4G speeds, but you were close. You “sort of” have 4G.
The 5G REVOLUTION
Although the basic principles of the technology have largely remained the same, the radio frequencies that each generation operates on have fluctuated.
4G doesn’t work on the same frequencies as 3G, and 5G won’t work on the same frequencies as 4G.
That means that with each rollout, new hardware needs to be developed to handle the new generation. If you have a 4G phone, it will never be able to truly manage a 5G connection….so yes you will have to buy a new phone to use that technology.
Each form of wireless technology uses different radio frequencies.
To reach the speeds necessary for 5G, mobile carriers are looking at using higher frequencies that aren’t being used as much for cellular service at this time and would offer more bandwidth to do more signal processing.
The problem is that higher radio frequencies don’t have as much range as lower frequencies, which means less coverage area. But, if carriers can solve the coverage issue, high-frequency 5G will offer multi-gigabyte-per-second speeds (up to 10 times faster than 4G), latency (responsiveness) as low as one millisecond, and allow much more traffic than 4G.
#5 COMPARING 1G to 5G
#5B Supporting Companies
#5C Current Global Usage
#6 “CON’s” OF 5G
Tests are showing that current 5G devices battery reserves are approximately 4 hours or less.
Due to the increased frequencies needed to support 5G service there is a problem with heat being generated by the devices inside the cell phone and it’s inability to dissipate this heat adequately.
WHATS REALLY AHEAD?
Carriers are already starting to unveil their 5G-E networks, although some of them is not true 5G NR yet.
From T-Mobile website:
” At this time T-Mobile has what they call 5G E ( actually rebranded LTE Advanced) service operational now, however during channel congestion, customers using 50Gb or more will notice reduced speeds due to data prioritization. “
Verizon, Sprint and ATT are all rolling out versions of 5G-E and are evolving very quickly.
They also don’t have much true 5G mobile equipment available yet because of the limited infrastructure.
Much like 4G LTE, 5G Evolution ( Or LTE Advanced) is the precursor to true 5G NR.
People wanting the high speeds and low latency of 5G will likely still have to wait a few years.
Network Function Virtualization (NFV) is a prerequisite for network slicing, intelligence at the edge and other essential 5G features that will power the delivery of IoT and AI-based services.
Security issues, standards development and the requisite CPU horsepower to drive virtual functions are some of the many obstacles being tackled by NFV developers.
The millimeter wave is another essential 5G ingredient that can present technological and logistical challenges. Due to the limited range and inability to transmit through solid objects, the sheer volume of antennae required introduces hurdles that can only be addressed through methodical, incremental deployment.
Spectral efficiency, measured in (bit/s)/Hz, is currently gated by the Shannon Limit which defines the maximum rate that data can be sent over any medium with zero error.
This theoretical ceiling is much less than what is expected and required for 5G deployment. Only Massive MIMO, MU-MIMO and beamforming, utilizing large antenna arrays, will enable 5G to effectively circumvent this natural speed limit.
It’s estimated that no sooner than 2021 or 2022 and no later than 2028, most carriers will offer true 5G NR networks and true 5G NR-specific devices……meaning that it will be NEW CELL PHONE shopping time.
The amount of technology and data concerning 5G NR is absolutely daunting.
With all the new releases and introduction of 5G NR equipment and devices at CES 2020 this week, I encourage you to research any aspects of tonight’s topic so that you can get all the latest information and answers you seek.
January 12, 2020 at 8pm
Radio Modulation, your microphone and how to talk to it.
Tonight we will destroy several myths that some folks have about modulation with sound technical and engineering facts.
Tonight’s moderators have a combined field experience in the commercial and broadcast communications field of over 100 years, take advantage of that fact tonight.
Those of you that feel you have this down pat …..don’t go away, but participate in the discussion. You may leave tonight’s TekNet with a piece of information that you didn’t know, how cool would that be.
I strongly urge the newer users to FM communications to take some notes, and ask questions so that this information is completely understood.
Your going to see how and why it is so extremely important for you to learn how to talk to your microphone.
Why and how proper transmitter deviation can mean the difference between you being heard and understood even in a weak or low signal quality condition.
January 5, 2020
Capacitor, ESR testing and recapping equipment
The moderator for tonight is NO7BS Kirk
#1A Capacitor Wizard
#1B Vintage Checker
#1C Newer Cap Checkers (single board)
#3 Leaking Caps
#4 Good 470uf
#5 Good .01uf
#6 Bad .01uf
#7 High Voltage Caps
#8 Start Cap
#9 Bad caps that were changed in the last few months
December 29, 2019
LED’s & how to use them.
Design terms disclaimer— Tonight is not the place to go into the finite calculations of ohm’s law. Not all LED’s & transistor parameters are the same, but are readily available for your design considerations when designing a circuit from a plethora of sources.
LED’s, what are they really?
An LED, which stands for light emitting diode, is a semiconductor diode that glows when a voltage is applied.
In comparison to an incandescent light bulb, the incandescent light bulb works by running electricity through a filament that is inside the glass bulb. The filament heats up and glows, and that creates the light, however, it also creates a lot of heat. The incandescent light bulb loses about 98% of its energy producing heat making it quite inefficient.
The LEDs are based on the effect of electroluminescence, that certain materials emit light when electricity is applied. LEDs have no filament that heats up, instead, they are illuminated by the movement of electrons in a semiconductor material, usually aluminum-gallium-arsenide (AlGaAs). The light emits from the p-n junction of the diode.
When did this research start? (A little history)
Discovered in 1907 by British radio researcher and assistant to Guglielmo Marconi, Henry Joseph Round, while experimenting with silicon carbide and a cat’s whisker.
It wasn’t until years later in 1961, Robert Biard and Gary Pittman invented and patented an infrared LED for Texas Instruments. This was the first LED, however, being infrared it was beyond the visible light spectrum. Humans can not see infrared light. Ironically, Baird and Pittman only accidentally invented a light emitting diode while the pair were actually attempting to invent a laser diode.
In 1962, Nick Holonyack, a consulting engineer for General Electric Company, invented the first visible light LED. It was a red LED and Holonyack had used gallium arsenide phosphide as a substrate for the diode.
Holonyack is called the “Father of the light emitting diode” for his contribution to the technology.
In 1972, M George Craford invented the first yellow colored LED for the Monsanto Company using gallium arsenide phosphide in the diode. Craford also invented a red LED that was 10 times brighter than Holonyack’s.
It should be noted that the Monsanto Company was the first to mass-produce visible LEDs. In 1968, Monsanto produced red LEDs used as indicators. But it was not until the 1970s that LEDs became popular when Fairchild Optoelectronics began producing low-cost LED devices (less than five cents each) for manufacturers.
In 1976, Thomas P. Pearsall invented a high-efficiency and extremely bright LED for semiconductor materials optimized for optical fiber transmission wavelengths.
Are LED’s AC or DC?
LED’s are a device that responds to a dc voltage between the P-N junction of a diode.
LED’s are very sensitive to current and should normally be used with a current limiting resistor to allow no more than 20-22ma of current to flow through the junction.
This is not a hard rule, as IR LED’s typically operate at 100ma depending on frequency and output and can handle as much as 1amp pulse.
Using the correct current limiting resistor, LED’s can respond to AC and DC voltages. Remember the positive half of a sine wave.
For example to use an LED with 12 volts DC a resistor of 560 ohm is (minimum) is correct for 22ma., for 5 volts DC a resistor of 150 ohms is correct for each segment of a 7-segment LED display (photo #8) or individual led. You can always use a higher resistance to provide lower current to the diode or for overall lower circuit current consumption. A higher ohmic value can be used if the led is too bright.
#3 8000mcd White
Many of today’s led’s are very bright compared to led’s manufactured just a few years ago. I use 4.7k resistors for some newer High Output leds that are extremely bright and being sold as regular LED’s.
Here I am testing an LED with a 2032 Lithium battery, there is no need for a current limiting resistor here.
#5 400mcd Red (pre 2005)
#6 2000mcd Red (2018)
#7 IR, Bi-color, Dual LED, Multi-color
#8 7-segment display
What can we use LED’s for and how?
One of the most common uses is to tell you if your circuit is energized or operating properly.
Example is the green led on most new radios indicating power on or a received signal and red to indicate the transmitter PTT line is active.
A few schematics…
Multi-color and RGB LED’s
Due to the complexity of the micro controllers that are built into each of these 64 color LED’s, Pixels contained within the intelligent digital interface data latch signal shaping amplification circuit, power supply circuit, a built-in constant current circuit, high precision RC oscillator, the output is driven by the patented PWM technology, effectively guarantee the pixels in the color of the light high consistency.
I am saving this technology for a future Tek Net. As you can see it is very involved and will have it’s own Tek Net.
Some future topics…I would like your vote tonight.
1- Preventive Maintenance
2- Roll your own, DIY building accessories
3- Test Equipment, Buying, Building, Restoring, Using
4- HF Equipment & antennas, Choosing what works for you
5- Power Supplies Analog, Switching
6- Station Grounding, AC & DC
7- Coax Cable, What is junk or Gold?
8- Sunspot activity is coming, get ready.
9- Satellite Communications, What you need to do to do it.
10- Digital modes, What makes them different
11- Capacitor, ESR testing and recapping equipment
December 15, 2019
All about the popular 18650 Lithium ion battery (almost)
For informational purposes only, DO NOT DUPLICATE!
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 incorrectly 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.
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, but I do attempt to know as much as I can when working with electronic components….including batteries.
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. Some different types.
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.
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.
REAL QUALITY AND FAKE 18650 BATTERIES –
The big four quality 18650 manufacturers are SONY, SAMSUNG, SANYO & LG.
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 –
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.
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.
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.
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.
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 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.
The good thing is that they can be identified very easy by color.
The 2000mAh cells are pale orange.
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.
Use a 60 watt soldering iron with a chisel or conical tip at least 1/8″ wide.
Silver-Bearing (62/36/2) solder or at least a quality 60/40 solder.
Using a sandpaper or a fine file, scuff the surface you are going to solder. About an 1/8″ is big enough
Tin the wire that your going to attach.
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.
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.