Next HARC TEK NET will be…..
July 5, 2020 2020 at 8pm
“Adding an analog “S” meter to a radio with digital display.”
* * * * * * * * * * * * * * *
WELCOME all to the Henderson Amateur Radio Club’s TEK NET
Subjects that have already been discussed will be displayed in GREEN text to show it has been archived.
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 yoo
ARCHIVED TEK NETS
Aug 11, 2019 – Power supplies- analog type- WB6AMT
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 12, 2020 – Radio Modulation, How to talk to your Mic-WB6AMT
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 14, 2020 – Repeater 100, Overview of Repeater Basics – WB6MIE
June 21, 2020 – ASK THE PROS” Night
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.
The following audio clip was created by Dave AG7ZF so you can enjoy this evening’s narrative of the entire net.
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.
HOW TO FIX A NON-CHARGEABLE BATTERY ( Less than +2 volts)
When an 18650 battery always shows that it is not charging or charged (normally a green light) but has a voltage of 2 volts can cause the charger to misread the battery and over-charge causing over-heating.
With a properly charged good battery (measure +4.2 volts) you can sometimes jump start a cell by connecting the good cell (same type and size) with a pair of clip leads to your SICK battery for no more than 20 seconds. Positive to positive and negative to negative, while feeling the batteries for over-heating. The battery being jump charged may be a little warm. Measure the battery voltage and if it is over 3 volts, cycle it through a charge cycle in your charger.
Often times you have just resurrected your battery back from the dead.
When charging lithium-ion cells always check and see that they are not overly hot, as cells go bad they develope chemical issues that can cause excessive heat and internal gases to build up.
When in doubt, if they are out of waranty…to be on the safe side…..trash them.
WHAT IS A CID – HOW TO FIX AN OPEN 18650 BATTERY (0.0 VOLTS)
For informational purposes only DO NOT DUPLICATE!
For a video, go to https://www.youtube.com/watch?v=1w3Tv1Jg0ps
Quality 18650 battery chargers –
Here is a downloadable nine page document with additional information about the 18650 battery :
Google 18650 batteries for more ( a LOT more) data on this new KING of The HILL in batteries.
See you next week!
December 8, 20
19 Tek Net will be on….WINTER FIELD DAY – January 28-29
Where will it be in 2020?
Will you commit to being an operator or logger?
How about an attendee to help out with visitor control?
Have you participated in Winter Field Day before and where?
What bands do you prefer to operate?
Do you operate a radio or prefer to be a logger on the computer?
Do you have a radio or antenna to loan for the event?
Can you assist with setting up the operating positions?
What are your suggestions for field day based on your past experiences?
December 1, 2019
Grounding concerns from Motorola’s R56 Manual
Your moderators are WB6MIE Tony Dinkel and NO7BS Kirk Nemzer
November 24, 2019 Tek Net will be on….
We will continue with a few D Star questions that were sent in earlier and have some general discussions depending how long the D Star talk takes.
November 17, 2019 Tek Net will be on….
“D Star In’s & Out’s by NO7E”
Please follow along at Chris’s Website:
November 10, 2019 Tek Net will be on….
“ASK THE PROS”
Tonight’s attending PRO Team-
To clarify IT issues is Shane Huston KG7QWH
Restoring vintage radios & repairing radio equipment Kirk Nemzer NO7BS
Homebrew building and modifications to radios
& T-Hunting Earl Lizardi WB6AMT
RF & Antenna Designs & Propagation for Ham, Commercial, Broadcast Tony Dinkel WB6MIE
D Star questions and registration Chris LaRue NO7E
We welcome opinions, questions and information from all of the check-ins every week, including a question from previous discussions.
11/3/2019 Why should I turn my radio on other than for nets
(Open forum type discussion)
#1 Why did you get a ham license?
9 stations checked in…9 different reasons to get their license.
#2 What steps did you have to take to get your license?
This was also mentioned by many as they answered question #1.
#3 How many years have you had your license and have you operated the entire time.
This evenings check-ins total more than 286 years of amateur radio operation.
#4 What do you find enjoyable about your “ON THE AIR” time?
#5 Do you think getting your ham license has made you more receptive to learning new technologies?
Without a doubt, ham radio for some was a gateway to newer technologies and aspects of ham radio.
#6 How would you change the way “NETS” are run?
#7 Do you think having two nets a week, Mid-Daytime & Nighttime would serve more club members?
#8 How many Nets do you regularly participate in?
#9 What type of Net would you like to see formed?
Interest in 10 meter operation was suggested and also possibly a sports oriented net.
Due to time constraints we skipped over a few questions for tonight, however i would still like to hear from folks on any of the questions we didn’t have time for.
Make use of a worthless radio chassis….
#10A MACHINING & ASSEMBLY
#12A MODIFICATION TO RA-42
#13A WIRING IT ALL TOGETHER
#13A1 Schematic Interface Strip
#13A2 Schematic of Radioless Node
#14A NEW FACE PLATE
#14D Final connections
#15 FINISHED……RADIOLESS ALLSTAR NODE
DTMF Remote Antenna Switch Project conclusion
The optional circuit shown is to indicate that a dtmf tone is being sent to the remote unit.
This is accomplished by using the MUTE output function of the encoder ic.
Tests have been made with 100 feet of RG6 cable TV coax, the unit switched antennas like it was suppose to. The photo is showing a 25ft RCA to RCA cable video cable for testing purposes.
The MT8870 DTMF Decoders are available online or from me for $4.00 each. The CD 4028 Cmos IC is available to anyone wanting to pick it up from my QTH at no charge.
The DTMF Encoder Ic is manufactured by AMI and is available from several vendors online.
The DTMF Encoder doesn’t have to be an S2559, there many different Touch-tone encoder IC’s out there ( example – TP 5089 $4.95 each), anything that will generate the touch-tones needed will work.
This weeks project is a remote controlled antenna switch.
This remote switch became a project after talking about DTMF signalling a couple of weeks ago.
One aspect of this switch is that we will power the remote relays and switch those relays using just RG-6 cable TV coax. DC power as well as the audio DTMF tones will be sent up the center conductor eliminating multiple conductors.
#2 Preparing the RF enclosure
#4 Ready to wire up
#5 Relay Wiring
#6 DTMF Touch-tone Decoder Receiver
#6A DTMF Decoder Digit #1
#6B DTMF Decoder Digit #2
#6C DTMF Decoder Digit #3
#6D DTMF Decoder receiving any other digit
#7 DTMF Encoder Circuit
#7A DTMF Encoder Board
#8 DC power/ Audio Injector circuit
Finished project pictures may be available at the beginning of next weeks TekNet as a recap from the previous week’s discussion.
Sept 29, 2019
Mounting mobile antennas for better performance
#1 The DB…
When we talk about a db rating, what is really being expressed?
dB is an abbreviation for “decibel“. One decibel is one tenth of a Bel, named for Alexander Graham Bell. The measurement quoted in dB describes the ratio (10 log power difference, 20 log voltage difference, etc.) between the quantity of two levels, the level being measured and a reference.
From a loss standpoint, if a measurement is deemed to be -3db between to levels, then that indicates a measurement of 1/2 or 50% lower signal level.
(You will see this described when looking at antenna feedline losses at a certain frequency limit on lengths of 100 ft or more).
A measurement level of +6db would indicate a signal level approximately 4 times the originating signal level on the reference antenna.
NOTE – It has stated that the energy level losses from an HT inside of a vehicle is at times -11.3db or greater than the same signal level radiating from a center mounted 1/4 wave whip in the center of the vehicle’s roof.
That means that a 5 watt HT will be radiating a signal approximately equal to .3125 watts out of the vehicle. (Conditions in the car vary)
#2 Some examples…
#3 Where to put the antenna
#4 Propagation between a 1/4 wave and 5/8 wave gain
Notice the plot at approximately 28 degrees.
#5 Beam Width
#6 Feedline losses
#7 Antenna Types
#9 Drilling a hole in my car will reduce the value.
As the manager of a Motorola Mobile Telephone Service shop in San Diego, Ca., I was asked that question very often by customers having mobile telephone antennas installed on their new vehicles.
Over the years I have questioned car dealerships, if a vehicle had a mobile telephone antenna (it was easier for them to understand why there was antenna on the vehicle) installed, would that affect the vehicle’s resale value when it was removed and a proper rubber flat antenna plug used to cover the hole.
My answer from the Mercedes, BMW, Chevrolet and Ford dealerships in San Diego, Ca. at the time all responded with no.
So….is it worth the trouble to install an antenna properly…absolutely.
Will it cost me money down the road….absolutely not (if removed and plugged properly).
Will it make a difference in performance, again… absolutely!
Antenna mounting holes can be as small as 3/8″ to 3/4″, all have plugs available.
CONCLUSION – Put a charge on that cordless drill and get ready to make your mobile radio talk and receive better than it ever has.
Our next “ASK THE PROS” Tek Net will be on October 13th.
Have your questions ready and plan to be there.
Sept 22, 2019
“What does the Touch-tone buttons on your HT do?”
#1A Single Tone & Dual Tone
#2 Examples – Encoders
#3 Encoder IC
#4 TelcoEncoder Schematic
#5 DTMF Decoders – Telco KT-247B
#5A DTMF Decoder – Telco LC type
#5B Decoder MT8870 type
#6 Decoder Schematic – MT8870 IC
Sept 15, 2019
“ASK THE PROS” Session for tonight.
Our distinguished panel of experts for tonight’s free form open forum has many years of practical experience in their respective fields and are still active today.
Subject matter can be about Ham Radio, Electronics, Audio, Video, Space Communications to some Nuclear Physics.
If we don’t have the answer for you it will be researched and the answer will be posted here.
Questions will be entered here along with their answers.
Tonight’s panel participants are….
WB6MIE – TONY DINKEL RF, HAM RADIO, AUDIO & MORE
NO7BS – KIRK NEMZER ANTIQUE RADIO RESTORATION, HAM RADIO, SATELLITE VIDEO & MORE
KG7QWH – SHANE HUSTON PROFESSIONAL IT SUPPORT
WB6AMT – EARL LIZARDI HOMEBREW BUILDING, COMMUNICATIONS
Be sure to state who you are directing your question to, so they can respond directly to you.
Sept 8, 2019
Building a disguised UHF base antenna
#5A Prepping the pieces
#6 Anchoring the antenna
#7 Mounting to a vertical support
#8 Mounting hanging from a tree or overhead support
#11 Dual band ground plane
Sept 1, 2019
General question/ answer discussion and swap meet listing
August 25, 2019
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.
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.
#8 Measuring vehicle alternator output
#9 Measuring 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.
Checking connections or solder joints that look suspicious.
August 18th at 8pm –
How does Allstar work
Allstar node located at Pleasants Pk., California WB6MIE repeater 446.120MHz
What is the difference between Raspberry Pi 3 and B+?
The Pi 3 Model B+ is based on the same quad-core, 64-bit processor, as the Pi 3Model B. Like the Model B, the B+’s is based on a Arm Cortex A53 architecture. However, the B+ ups the speed of the CPU to 1.4GHz from 1.2GHz in the original Model B, an increase of 16.7%.Mar 14, 2018
August 11, 2019
Astron analog power supply
#5 Adjustable regulator board
#6 & #7 Surplus equipment