Next HARC TEK NET will be…..

January 19, 2020 at 8pm  

5G Service…what is it really

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WELCOME all to the Henderson Amateur Radio Club’s   TEK NET

This is a new adventure and is open to everyone’s suggestions and ideas. The more discussions and comments the better. There are many hams with years of hands-on experience to share and many without that knowledge who wants to gain a better understanding of some of the many facets of amateur radio, communications or electronics.

Subjects that have already been discussed will be displayed in GREEN text to show it has been archived. Those will be at the bottom of the current discussion listed by date, for easy reference should anyone have a question concerning previous subjects.

We will have a round table type of QSO on all of the linked HARC repeaters. A roll will be established for that evenings net, for record keeping purposes.

After each photo, diagram or comment, I will ask for anyone’s comment or question.

The photos, drawings and diagrams found here will assist with visually understanding the subject for that net discussion.

The subject for the next net will be listed as soon as it’s available (typically Saturday afternoon the day before )  so you can look over the net’s topic for the upcoming Tek Net come Sunday night.

Participation is what will make this a success.

                       Send me your ideas for subject discussion

Past and future subjects for discussion: (No particular order)

    *  Aug 11, 2019 – Power supplies- operation and failures – analog type

  • Sept 1, 2019 – General question/ answer session & Swap meet listings

  • Power supplies- operation and failures –  switching types

  • Dec 1, 2019 – Grounding from Motorola Manual R56

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

  • Nov 17, 2019 – What is D-star

  • Nov 24, 2019 –  Continuation on D Star

  • Stealth or disquise antennas in an HOA

  • Sept 22, 2019 – What does the Touch-tone buttons on your HT do?

  • Aug 18, 2019 – How does Allstar work

  • Using commercial two-way radios on Ham frequencies

  • Dec 8, 2019 – Winter Fielday 2020

  • Ham swap meets, do you go?

  • Sept 29, 2019 – Mounting mobile antennas for better performance

  • Have you ever built or owned a repeater

  • Oct 27, 2019 – Make use of a worthless radio chassis….

  • What do you think of the audio on most repeaters

  • Nov 3, 2019 – Why turn my radios on other for nets?

  • What does it take to have a successful repeater

  • Building your own antennas

  • Sept 8, 2019 – Building a UHF disguise base antenna

  • Aug 25, 2019 – How to use a multimeter

  • What does a swr meter really tell you

  • Oct 5, 2019 – Remote HF Antenna switch project

  • What do we know about Hoover dam power plant

  • Nov 3, 2019 – Why should I turn my radio on other than for nets

  • Do you have or know about Solar power

  • Since being licensed, how have you seen amateur radio change

  • December 29, 2019 – LED’s – How to use them

  • December 15, 2019 – 18650 Lithium Batteries

  • Nov 10, 2019 – Ask The Pros Night

  • Jan 5, 2020 – Capacitor, ESR testing and recapping equipment


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.

#15G 5 generation network mobile symbol hologram


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.

MIMOMultiple Inputs/ Multiple Outputs for data handling ( both Cellular and Wifi service) 2X,4X, 4X4 

MU-MIMO – (Multi User Multiple Input, Multiple Output)

NFVNetwork Function Virtualization ( prerequisite for network slicing )

mMTC – (Massive Machine Type Communications) IoT applications

Mesh WIFI – ( Private systems at first )

CBRS – Citizen Broadband Radio Service (CBRS) at 3.5 GHz is about to become available

5G ACIAAlliance 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.



Ericsson AIR5121 4 with traditional LTE microcell on left

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 Usage5G-mmWave-28GHz-CEPT-report-spectrum


#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.


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.

In 1994, Shuji Nakamura invented the first blue LED using gallium nitride.

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. 




20191228_184802_Film3 - Copy (2)

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

20191228_180847_Film3 - Copy (2)


20191228_180915_Film3 - Copy

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)


Different types

#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.



POPULARITY – ( what do they replace)


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



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.

  • s-l300



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. 



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

maxresdefault (1)

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

The best confirmed capacity original cell at this point has 3400mAh. Second, their weight is lighter. Original cells are 45grams+. Fakes have mostly under 40g, and the worst quality ones are even 20g. Those have an effective capacity of under 500mAh, even if they state 4000mAh+ on the label.

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




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.


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

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

LG also has some new cells rated at 3100mAh.

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.



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.

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

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

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

  4. Tin the wire that your going to attach.

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

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



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.



For informational purposes only DO NOT DUPLICATE!



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


Quality 18650 battery chargers –

18650 Chargers




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

18650 Cells

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

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?

Times available.

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….


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….




#2   DISASSEMBLY800Maxtrac_1




















#10A  MACHINING & ASSEMBLY20191025_135958_Film3




#11A   MODIFICATIONS20191025_130751_Film3














#13A  WIRING IT ALL TOGETHER20191026_211131_Film3


#13A1  Schematic Interface StripEtxrenal Interface


#13A2   Schematic of Radioless NodeAllstar_Radioless_Node_Block





#13C  20191026_211223_Film3


#14A  NEW FACE PLATE20191025_210333_Film3






#14D  Final connectionsDSCN1970











DTMF Remote Antenna Switch Project conclusion


#2Antenna switch




#4Antenna switch Encoder

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.




  • Homebrew projects


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 enclosureDSCN1930






#4 Ready to wire upDSCN1939


#5 Relay Wiring20191006_174446_Film3



#6 DTMF Touch-tone Decoder ReceiverMT8870




#6A DTMF Decoder  Digit #1


#6B  DTMF Decoder  Digit #2



#6C  DTMF Decoder Digit #3



#6D  DTMF Decoder receiving any other digitDSCN1931


#7 DTMF Encoder CircuitEncoder


#7A DTMF Encoder BoardIMG0186A[1]


#8 DC power/ Audio Injector circuit20191006_174646_Film3


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…Loss visualization.


#3 Where to put the antenna


#4 Propagation between a 1/4 wave and 5/8 wave gainGain_plot_70cm_vehicle

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?”

#1  Frequencies



#1A  Single Tone & Dual Tone

dowsingle tonedymf wave


#2  Examples – Encodersty__90555.1522962981.1280.1280



#3 Encoder ICs2559_5089freqs


#4 TelcoEncoder Schematic



#5 DTMF Decoders – Telco KT-247B247b

#5A DTMF Decoder – Telco  LC  type


#5B Decoder MT8870 type


#6 Decoder Schematic – MT8870 ICimages







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….


NO7BS – KIRK NEMZER    ANTIQUE RADIO RESTORATION, HAM RADIO, SATELLITE VIDEO                                             & MORE




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



#2Looped J-pole antenna


#3Bending Chart




#5A    Prepping the piecesEnd cap

#5BT pieces

#6 Anchoring the antennaInside T



#7 Mounting to a vertical supportBottom

#8 Mounting hanging from a tree or overhead supportBottom2.jpg






#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.

images (1)


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


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.











Power Supply output



#8 Measuring vehicle alternator output

Vehicle battery

#9 Measuring Resistance









#10 Measuring current demand

LED current

#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






Hardware improvements from the Pi 3 to Pi 3 B+

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


August 11, 2019 

Astron analog power supply









#5 Adjustable regulator board


#6 & #7 Surplus equipment