Neutralization.

The word neutralization has many interesting meanings. For Mafia Dons, like the Tony Soprano types, the word has the definition of simply eliminating the competition in various criminal enterprises. 

Tony Soprano

For many Americans, they see neutralization through the lens of the midterm elections, in less than a year from now, to reverse the questionable actions taken in this past year. There seems to be widespread support for this type of neutralization based on the 2025 elections just held.

For me neutralization has to do with rigs I have built. The action of neutralizing a RF amplifier stage is to negate the situation where K*Beta = 1... also known as the Barkhuasen Criteria or in simple terms the final amp is oscillating!

Initially I looked at the output stage (12GE5) of my Hybrid Wireless set, and it all looked pretty good. As built and after initial testing it did not look like any neutralization was required. I swapped in a new tube as the original tube was stressed from too high a bias and lots of key down testing began show signs of lower power output, so I installed a new tube. 

In looking at the output with the 2nd tube, it looked pretty clean and I moved on. Then I did some additional testing and at certain settings of the BPF it would oscillate and the signal did not look clean. The light bulb went on, and I concluded that I needed to install a neutralization circuit.

So, what is neutralization in RF terms, what does it do and what comprises a neutralization circuit. So, I asked copilot to summarize RF amplifier neutralization.

Neutralization in RF amplifiers is a technique used to prevent unwanted oscillations by canceling internal feedback between input and output stages.

Here’s a deeper look into what it is, why it’s necessary, and how it’s implemented:

📡 What Is Neutralization?

Neutralization is a method used in radio frequency (RF) amplifiers to eliminate positive feedback caused by parasitic capacitances—especially between the input and output terminals of active devices like transistors or vacuum tubes. These parasitic paths can unintentionally turn an amplifier into an oscillator.

⚠️ Why Is Neutralization Needed?

• Prevent Oscillations: Internal feedback can cause the amplifier to self-oscillate, disrupting signal amplification and degrading performance.

• Improve Stability: Neutralization ensures the amplifier operates stably across its intended frequency range.

• Enhance Performance: By eliminating unwanted feedback, it helps maintain gain, bandwidth, and selectivity.

Oscillations are especially problematic in high-gain or high-frequency amplifiers, where even small feedback can lead to instability.

🛠️ How Is Neutralization Done?

Neutralization involves introducing a feedback network that provides a signal equal in magnitude but opposite in phase to the unwanted feedback. This cancels out the internal coupling.

Common methods include:

• Capacitive Neutralization: A small capacitor is connected between the input and output to counteract the interelectrode capacitance (e.g., base-collector in transistors).

• Transformer Coupling: Using a transformer with a center-tapped secondary to inject out-of-phase signals.

• Balanced Circuit Design: Employing symmetrical layouts to naturally cancel feedback paths.

• Y-Neutralizing Networks: Fixed elements designed to counteract reverse transfer admittance in transistors.

For vacuum tubes, neutralization often targets the grid-to-plate capacitance, while in transistor circuits, it focuses on collector-to-base capacitance.

As a starting place I used a 10pF 3KV fixed cap connected from the plate circuit to the grid circuit and several things happened. The occasional hinky looking output on voice peaks is no more and the power output across the band pass is fairly flat. As "W" once proclaimed... Mission Accomplished!

Them that know can make things go.

The government shutdown (the longest ever) is temporarily over, but the damage is done, and the finger knows where to point. One of the neutralization definition processes is now in play.

73's

Pete N6QW

The answer is subtraction.

A possible answer to the question about the obvious chaotic behavior of some elected politicians. Each day they know less. It is all about subtraction.

So now back to some radio stuff. I continue to look at the possibilities of converting the SSB version of the 23 channel CB radios to 10 Meters. The Crystal synthesized versions look particularly attractive for conversion with a specific look at the Cobra Model 134 and Model 138. The chart below is chock full of information on how the synthesis works.

There is a bit of magic taking place and the chart tells the tale. Ten synthesizer crystals plus the BFO crystal give you 3X23 or 69 channels of either AM, LSB or USB signals.

With a single BFO frequency it is possible to have LSB and USB simply by picking the correct LO. For LSB and AM with a 7.8205 BFO and an LO operating at 19MHz, the output is in the range 26-27MHz which is an additive mix. Now if you shift the LO to 34MHz two things happen: we use the subtractive mix where 34 - 7.8205 puts you in the 26-27MHz range with the 2nd part Sideband Inversion and the signal is USB.

The footnote shows how the A + B frequencies are in the 19MHz range and then adding the C frequencies make the 26-27MHz range. But they don't show how to get to 34 MHz. If we take the A + B + 2*C that equals 34 MHz and then subtract C in the mixer stage and you have A +B +C but Upper Sideband.  So, for USB there is mixing circuitry in the radio to add the two crystal frequencies plus sampling the BFO and doubling that output to add to the two crystal frequencies.

This is where the Arduino and the Si5351 can replace the Crystal synthesizer. You would only need one channel as the Si5351 would tune 20.497500 to 21.197500 MHz giving you 28.3 to 29 MHz LSB and AM

For USB the Arduino / Si5351 would have to tune 36.102500 to 36.802500 MHz to tune 28.3 to 29MHz Upper Sideband. Mind you the LO has to shift up in frequency in either mode to cover 28.3 to 29MHz.

BTW something I did with my now gathering dust Bitx 40. Upon getting that radio, I disabled the on board "drifty VFO" and replaced it with an Arduino and Si5351. I used the same approach as above to put the Bitx40 on USB so I could talk to that group that uses USB on 40M and for FT-8. The BFO does not move to give LSB/USB but the simple change in the LO frequency range made USB possible. A simple toggle switch to select LSB or USB signals the range change to the Arduino.

Them that know can make things go. The Cobra 134 or 138A can be had for around $70 and the addition of a digital LO about $20.  So, if you had a hundred dollars floating about after donating $100 to feed the hungry on Thanksgiving this would be a candidate.

Speaking of donations, I stopped by the rectory of my local Catholic church to drop off a check to the St. Vincent DePaul Society for food for the hungry. It was shared with me that this year the requests are outstripping the resources available. 

Mind you I happen to live in a high-tech town with a world class pharmaceutical manufacturer and even a branch of a company who makes the Si5351 so lots of employers. But it also is home to many who work in agriculture growing, cilantro, strawberries, artichokes and peppers. Many of these workers no longer go to work because of the ICE raids.

We need to focus beyond a deportation mentality and fix the immigration system. But is it more fun to play dress up in BDU's sporting an M-16 and herding aliens into buses bound for detention centers or the really hard work of providing for legal immigration. It will not happen soon and so the cosplay continues. 

73's

Pete N6QW

Veterans Day 2025

To all those who served and are now serving... Thank you for your service!

Saying Happy Veterans Day to me sounds most inappropriate! While a Federal Holiday and no mail or your bank is closed it is a day of reverence, respect, reflection and recompense.

We owe veterans for our freedom and for those in power today, I wonder if you understand that simple fact. Yet, after serving our country their service seems to be forgotten. Possibly it is a result that often government leaders never served. 

The last four presidents did not see active military service yet were responsible for sending thousands of military personnel into harm's way. When you have been there and done that, it adds a whole new perspective to the decision process.

Yes, you are wondering about that last statement regarding US Presidents and military service.

Here is the list of 15 U.S. Presidents who have held the office without prior service in the military.

1. John Adams
2. John Quincy Adams
3. Martin Van Buren
4. Millard Fillmore
5. Grover Cleveland
6. William Howard Taft
7. Woodrow Wilson
8. Warren G. Harding
9. Calvin Coolidge
10. Herbert Hoover
11. Franklin D. Roosevelt
12. Bill Clinton
13. Barack Obama
14. Donald Trump
15. Joe Biden

Two on that list served as wartime presidents and made the declaration of war (WWI and WWII). We seemed to prevail, but did they really understand what it is like to face the potential of death on a foreign soil?

Think about our veterans and how they are treated once they have served. It seems like veterans' benefits are an afterthought and just as likely to be zero balanced to offset perks to the super wealthy. 

73's

Pete N6QW

Marketing information

Happy 250th Birthday to the US Marine Corps. Semper Fi! Having served with the Marines as a part of RLT4 in May of 1965 at Chu Lai, they have my greatest respect and admiration.

Yes, I did take post graduate course work in Marketing and most definitely that often colors what I see. In the last two weeks the highest viewed posting remains the one with BB on the beach.

Marshall McLuhan, a Canadian marketing guru of the 1970's proclaimed "the medium is the message" as evidenced by TikTok. What is clear based on tests I have run on the blog... Hot looking women assures blog readership. The Medium is the Message, looking at a photo of BB suggests some hot info on ham radio stuff.

Thus, our subject for today will not get a lot of views. POTA Antennas, now that has a nice ring to it. As usual something turned up on my smart phone about Wolf River Coils 

So, Let's Talk About Antennas!

In a limited look see, one thing caught my eye was a really light weight 217-inch telescoping antenna, (about 18 feet) which means by itself it is a full quarter wavelength on 20 Meters. This means it can be used direct on 20 Meters and above without the base loading coil. 

The costs don't seem exorbitant, and I was thinking of N2CQR who operates several times a year from HI7 land. A pair could give him a phased array vertical beam at 70 feet in the air. Four of them have the makings of a horizontal 2 element 20M beam antenna. Kind of cool.

My heart goes out to those who will potentially lose their SNAP benefits not because they did anything wrong but because of a few vindictive individuals. 

In case you might be wondering about Tariff's and their economic impact. The Smoot-Hawley Tariff Act of 1930 enacted by POTUS 31, according to Copilot AI actually made the Great Depression worse! Read the rationale for the act some 95 years ago and what do you see. The medium is the message!

Them that know can make it go.

73's

Pete N6QW

Right Under our Nose.

The news is so full of questionable actions that if known by our founding fathers they would be grieving at a failure of our democracy. Suddenly there is no rule of law, and you have to scratch your head about how the Supreme Court lets it happen... 

Never mind, as we common folk who believe in democracy have no say in the matter and the fickle finger of blame doth knows where to point. 

Americans who made that choice a year ago surely must wonder what they did. There always is an accounting so keep that in mind.

Right under our nose are some really cheap commercial SSB radios designated for Maritime use that are usable "as is" on our ham bands. Let's perk up your interest as these can be had for under $100. Here is a prime candidate the Stephens SEA 222

This particular unit tunes through the 15M Band, USB at 150 watts out. Philips has a radio product which is essentially a stock SEA222 but added a front panel switch to provide USB/LSB functionality.

Before you hit Buy It Now, that $100 could buy 20 Turkey Day Dinners at one of the relief agencies sponsored events. Feel good and avoid spending another $100 on a radio you don't need and instead feed some hungry Americans.

Things are very interesting for six of the current top government officials. Citizens outraged at these officials have made it impossible for those six to live in regular homes like you and me. They are now hiding out at undisclosed locations on military bases. Someone suggested it is like being in prison on a work release program where you go to work during the day but are behind the locked gate at night. Also reported but not verified is that we are paying for their "safe houses".

Them that know can make things go.

If being out of a job or having to float a home loan to buy a pound of hamburger requires a diversion, then read about the 31st President of the USA, a Republican who was highly unpopular for what he failed to do. POTUS Thirty-one (31) had two sons one of which that had a direct connection to ham radio. This son, the eldest, even sported a prestigious 1X2 call with a 6 in it sort of like some of us. Another clue is that 31 was only one of a few presidents who had an engineering degree... from Stanford no less. Another one was Jimmy Carter, a Democrat and US Naval Academy grad who also had popularity issues. 

73's

Pete  N6QW 

Is Anybody Listening?

Do we really listen? Yesterday's post was about watching so only natural we ask about listening. This has nothing to do with the political chaos of our current government... they stopped listening even before they officially took office!

The listening is about Ham Radio stuff. We are not talking about listening for bad signals or that the op at the other end is 33.5 Hz low in frequency. No, it's just about plain listening to what is being shared during a QSO.

A Ten Tec Omni VI Radio and a Cute YL. I bet she gets listened to on the air.

This discussion for today is about a QSO I had yesterday with my 40M Hybrid Wireless running barefoot at 20 watts. The occasion was that until yesterday I had only one 12GE5. In the mail yesterday was a spare tube and I wanted to test it in the circuit to see what it would do. I no sooner get it installed, and I hear a CQ originating from a station a little north of San Francisco, roughly about 400 miles. 

I respond to the call and he comes back to me. So far so good. I then told him I was running a homebrew hybrid transceiver at 20 watts. He comes back and says I was doing OK. He then says I have been a ham since 1963 and am 78 years old and we used to build all of our rigs but no more. 

I come back and say I have been licensed since 1959 and soon will turn 84. His next over was what kit did you say it was? I came back not a kit totally homebrew with a digital LO that is on frequency. He then said I have to run and a friend of his broke in and it was like I was no longer there.

My supposition is that here was someone older than him and a ham longer than him could actually build a quality radio and have QSO's. I have heard this guy on various nets, and it is pretty obvious he only listens to himself.

So, who do you listen to?

Them that know, listen and then make it go.

73's

Pete N6QW

Is Anybody Watching?

The question is not about TV, nor the Reverse Beacon Network or a DX now on the Air website but information from our government. I was surprised at the volume of information from the Bureau of Labor Statistics  

The array of information is staggering and my visit there was prompted by something that simply showed up on my phone. The lead was that the job creation for October was another "low" number in the less than 50,000 range.

The presenter had an impactful message (aside from the white turban and long black beard) in that the low number was driven by two major factors the first being that the tariffs were impacting the jobs being created and secondly that the use of AI was eliminating jobs. 

Note the Young Employee's!

The AI had two subsets that is driven by one a response to economic conditions (tariffs) and the second is the change of economic model to producing more of a less expensive product or service with a lot less manpower. 

Read AI doesn't need fringe benefits, maternity leave, healthcare benefits, sick leave, vacation time off, cross training, attending seminars, annual reviews, or pay raises. In the AI model a couple of Nerdy guys wearing Hawaiian shirts and flip flops are the total working staff!

Then the presenter made an interesting point, and this really caught my attention. He focused on the current young generation in the work force by saying this is a great opportunity for you. 

He then cited their skill set and being a really good fit for the new economic model. For any employee with 15 years of work experience the newbie knows more about computers and how to find information or how to describe a problem. The message is clear the experienced workforce using the old model will be simply "redundant" as their job skills are not compatible with the AI Model.

He then set up a problem situation that involved a Hawaiian Shirt that came in a special pattern and had unique colors. The task presented to the newbie and the 15 years of experience employee: find it and buy it for the cheapest price. For the newbie it is just another day at the office, and he wins the competition. 

The flaw I see in this analysis is that the AI is searching for information on a vast database that exists right now. So, what part of AI is expanding that database. Unless attention is paid to new R & D, then we soon will reach a saturation point where no new information is being added. Will we all be replaced by machines?

We already know that AI can design an SDR SSB transceiver, but can AI think about a mode beyond DDC SDR. When our ham operator was pounding brass in the 1920's did, he ever envision the power of SDR in the 2020's? Maybe not SDR but communicating one letter at a time was sure on his brain and we can see the evolution to phone, SSB, Digital Signal Processing and now SDR. How will AI make that same leap?

Think of those who will have an empty table this Thanksgiving and do your part no matter how small.

Totally in line with today's post, the posting in the last 10 with the highest hit count was the one of BB on the beach. Hmmm says a lot about the OT ham operators.

73's

Pete N6QW

Holiday Gift Suggestions.

Many blog readers are quickly jumping to the text looking for photos of gear they absolutely have to have. But my gift suggestion has nothing to do with that sort of gift. 

Many of Americans are hurting right now from a job loss or out of work due to the government shutdown. So, instead of buying a new radio or more radio parts how about spending some of that cash to help your fellow Americans by providing resources to organizations that are hosting meals for those affected. Your local Salvation Army, St Vincent DePaul and other church/civic organizations will turn your cash donation into food to feed the hungry. Any amount, even small amounts of cash will help.  

We all know this situation is likely to get worse and the end is at least another three years away. It is an impossibility to explain to those affected how tariffs are such a good deal.

If an IC7300 cost $1000 one of those organizations has said they can feed several hundred Americans Thanksgiving Dinner for that amount.

I will have an empty seat at my Thanksgiving table this year and so it pains me to think that many of our fellow Americans will be at an empty table, one with no food. Think about that in the context of the cost of a new 90,000 square foot ball room at 1600 Pennsylvania Avenue. 

When we as a nation turn on our back on our own, then we shake the very foundation of our core founding principles. 

Them that know, know we have responsibilities to our fellow Americans who are suffering right now.

73's

Pete N6QW

The Johnson Viking Model 352 CB Radio.

E F Johnson 40 Channel CB Radio

One technique employed by a Silicon Valley firm when recruiting new employees for their advanced product division was to show a photo of an item and then ask the candidate... what do you see. The answers were all over the map but usually the successful candidates had a one-word answer and that was opportunity.  Today's post is about opportunity. 

If your response after seeing today's photo was a CB radio... you failed as you should have given the one-word response.

Many SSB CB radios have been "converted" to 10M operation and usually certain ones that have a programmable PLL are sought after. A bit of reprogramming and tweaking the RF circuitry and you are there. You can ask AI, and they will tell you the ones that meet that criteria, and you are usually steered to the PLL models.

Early on, before the PLL and when there were only 23 channels the CB radios used crystal synthesizers. Banks of crystals were selected so that through a mixing of crystal frequencies you generated the 23 Channels. You can see why the PLL's types are favored. To move the crystal synthesized radios to 10M required many new custom crystals. But no more.

One particularly interesting CB radio is the Johnson Viking Model 352 that used the 23 Channel Crystal Synthesizer and here is a block diagram.

The lower part of the diagram shows the Crystal Synthesizer and after all of that mumbo-jumbo produces a 34MHz LO and with a 7.8MHz IF (pretty much an industry standard) you get the CB frequencies.

Here is a frequency chart of the synthesized LO Frequencies.

You just know it's coming... Rip Out the Crystal Synthesizer. In its place and for $20 build an Arduino Nano based, Si5351 LO and small OLED display and program it for 35 MHz and you are on 10M after Peaking and Tweaking the RF Stages.

Actually, there may be a bit more involved to make it work on LSB, USB and AM but that could be addressed by having the Digital LO also generate the BFO signals. There are several Model 352's currently listed on eBay and a "beater" can be found for under $50.

But I keep forgetting, to do this you do have to know something with the 1st on the list is the ability to see opportunity followed by knowing something about electronics. The electronics part is like reading schematics and circuit tracing and how to program an Arduino. We are now back to less than 1% and maybe even only 0.5% who could pull this off. But the prize is a 10M SSB radio for less than $100 and you modified it. 

Them that know can make it go.

PS. Yesterday's poor stats on the number of blog viewers was simply a test that either there is a dislike of Gumbo or maybe Mike Johnson. Surely it was not about the 5763 Vacuum Tube. I keep data and it is telling. 

PPS. Think 6 Meters. With the Si5351 a CB to 6M conversion is on the table albeit a bit more complex.

73's

Pete N6QW

Pot Pouree! Like Gumbo... smells good but not sure of the contents

GUMBO A heavy thick stew consisting of components representative of a host of cultures and usually associated with the home state of Speaker Mike Johnson. The components can vary and some seem arcane.

I have hard data that the blog must contain a photo or video to get over 100 views and photos like yesterday's get way and I mean way over 100 views. So no risqué photos today so maybe only 50 views. But it is my blog. 

The above data sheet is for a 5763 Vacuum Tube which used to be a staple for many 1950's/60's low power CW transmitters. With a good design you could get 10 watts into the wire on 40M. 

I mention this tube because it is one of those hidden gems. About a year ago I picked up four of these NIB for $10 on eBay. Now that I have a spare HV DC power supply floating around which was noisy in a receiver but does not have that problem on transmit, the temptation is to draw those two together. There are many simple designs you can find on the internet or through the use of AI.

(Yeah, I know too lazy to look so click on the link)

Speaking of AI, always verify the result as often it is wrong. Here is a problem for you. You have a T-68-2 iron powder toroid that has 14 turns of #16. What is its inductance. You can use the calculator in the Kits and Parts website (W8DIZ Toroid King) Then ask at least two AI sites. Compare notes. 

Well, yesterday I calibrated my Hybrid Wireless using my Hermes Lite 2.0 as a measurement device and the difference is less than 10Hz. So, let's see how many comments about being high or low I get.

Yesterday I added the S meter sensing circuitry and installed the linear amp switching. Using the Hybrid wireless as a driver, my SB200 spits out 300 watts. (About a 11.7 dB gain) I know it's not full legal limit but a lot better than 20 or 5 watts. I easily worked into the Midwest last night with good signal reports.

I have been noodling an AGC circuit for the new rig and I think I have something that will work. The bigger problem is getting access to the circuitry to make the installation.

That's All Folks and so I leave you with... Them that know can make it go!

73's

Pete N6QW

Shocking! You are almost 50Hz high in Frequency!

The Ham Radio technology of today takes us way beyond just making contacts or endlessly yelling into the Microphone "CQ POTA". It has become evaluative! We lust to know how our signal sounds at the other end of the circuit and those on the other end lust to tell us something is not right!

A young BB ~ Now > 80

(I'll do anything to get you to read the Blog.)

I smile when I hear signal reports: "well, you are only about a 5X7 and I can hear every word, but you are not strong!" The report somehow leaves you with an expectation that unless you are 20dB/S9 then it is not a good contact. 

Last night I had the new 40M Hybrid Wireless Set on and just listening to various station, most of which were about 500 to 1000 miles away. I ran across that group that uses USB on 40M, and I switched over to USB and suddenly realized I never tried the new rig on USB. 

The net control then asked would anyone like to check in. The control station was in Colorado Springs, and this would be a good test of my 20 Watts on USB. 

I gave a call, and he came right back to me. In my return I gave my name, QTH, power level and that it was a new homebrew rig. 

The next over the control station says you sound good BUT you are off frequency and a bit high. Give me some chatter and I will tell you exactly. I comply and he says I am using my GPS locked frequency standard for measurement and you are less than 50 Hz high. I also got reports from net stations in New Mexico and Nebraska who commented that the rig sounded very good but no mention of being less than 5o Hz high.

So, a couple of Points to Ponder (PTP). I can tell a station being off frequency at the 200 Hz level but not down to less than 50Hz. At that value (<50Hz) does it matter. Well, I guess it does if you spent $8K on a rig and then that becomes the justification for the significant sum spent for ham gear.

The other point is the settings we chose to display. The step tuning range on the Nano/Si5351 was set to 100 Hz. Basically, it says that actual frequency between 0 and 49 Hz above the dial showing 7.227.000 MHz would register as 7.227.000 but if the actual frequency was slightly greater than 49 Hz then it would register as 7.227.100.

Thus, if I was less than 50 Hz high then my dial would still show 7.227.000. 

A simple cure would be once you tune in a station is to switch over the step tuning rate to 10 Hz and fine tune by ear the signal at the other end. This would then get you to within less than 10 Hz of being high in frequency. 

Of course, the other solution is a recalibration of the Si5351 to get it dead nuts on frequency. I have done that using my SDR tuned to WWV and with trial and error you can zero beat WWV on the SDR with the DUT (Device Under Test). 

Now a bit of boring math as we look under the hood. For some very good technical reasons I set the Digital LO above the operating frequency which also causes sideband inversion. Thus, the digital BFO for a 9MHz Crystal Filter is set for 8.998500 MHz resulting in LSB.

Then, the Digital LO is set for the sum of 7.227 + 8.8895 = 16225500 Hz (16.2255 MHz). If I were 49 Hz high in frequency that would mean that the BFO generation was off by 49Hz as that is the only variable. The BFO is actually at 8998549 Hz. But since we are reading to 100 Hz increments the dial would read spot on frequency. Recalibrating the Si5351 would generate 8998500 versus 8998549 Hz.

Them that know can make things go.

73's

Pete N6QW

Standard Time and you gained one hour of sleep. Fixing the Dawg!

You haven't heard much about my Hybrid Wireless rig lately as I have been busy "flattening the warts" and we now have a better product.

[I find that blog readers usually only get this far and then head off to other parts looking for items on new radios or new technology. You should at least scroll to the end and watch the short video as the radio now "barks up a storm" and signals seem to pop out of nowhere.]

Some of the issues were RF Feedback and noise issues along with a change in the bias circuitry. The $30 Amazon power supply I found later on had a noise issue. It was noticeable at low volume levels. I replaced that with a full wave bridge rectifier and now the screen voltage (and plate voltage on the receiver tubes) is 240VDC. The noise is gone.

I had to add some shielding around the steered 2N2222A, that is the Rx RF Amp and Tx Pre-Driver and 2N3053 Driver stage. I also swamped the input of the IRF510 with a 50 Ohm resistor. Now no more RF Feedback.

The biggest issue was the JF3HZB software! This was truly disappointing and on par with the hot looking woman who had nothing to say except focus on how good she looked.  I simply could not create a suitable BFO frequency that worked on both receive and transmit. I had to offset the BFO by some 2kHz and that was obviously wrong. The transmitted signal sounded like crap. Plus, there was no easy way to calibrate the Si5351. I went back to the Arduino Nano and the ILI9341 display... it was Right On The Mark! I note that the JF3HZB embedded Si5351 Files, (Si5351.h and Si5351.cpp files) are not the ones from Jason Mildrum, NT7S. 

The Nano system I reinstalled has Jason's Si5351 files... the result is a perfect fit. Using a Grayhill optical encoder, the tuning is smooth. The other bonus is I built in the capability to have an S Meter on the display.

A Return to the Digital VFO using the Arduino Nano

Shield over the 2N2222A and 2N3053 Driver. 50 Ohm Resistor on the IRF510 Board.

New Digital LO using the Nano and Si5351

These changes have greatly improved the functionality and operation of the transceiver.

Them that know can make it go! 

73's

Pete N6QW

November 1, 2025 and a change of pace.

 The 2026 Caterpillar Pickup Truck

With but two months left in 2025, it has been quite a year. Recapping, you disowned your two slug kids, finally you rid yourself of the nagging, dumpy looking XYL. As a bonus you now have two girlfriends, and you own two premium SDRs, one from Apache Anon and the other from FLEX. The 200-foot tower complete with the 16 element Log Periodic antenna is finally working and now you are looking for something exciting to do with $100K sitting in your checking account. 

Did I also mention that after listening to a presentation from Jason Huang you invested heavily into Nvidia. His idea is to take cloud computing that is tethered to servers sitting in large brick and mortar facilities and to link it to mobile radio networks without the servers. This spells a new ham radio option using Huang's idea.

So back to the chunk of change sitting in your personal checking account. To kill some time, you watched one of your favorite movies, The Fighting Seabees. In that movie John Wayne drives a CAT D7 into some fuel tanks which explodes literally roasting alive the Japanese landing force on Island X. It was then you remembered something about Caterpillar that you saw on a news feed.

Caterpillar for 2026 is now producing a high-end pickup truck.  This top-of-the-line offering is targeted at a $100K price point. It will have a 500 HP diesel engine. I have trouble thinking of power and horses in the same breath. Converted to watts that is 373KW. Imagine sitting atop a 373KW "leenear amp"... you are heard everywhere! 

The CAT pickup uses an industrial grade of steel construction which is aimed at longevity. Its drawbar pulling capacity rivals Ford and the Dodge RAM. So, it not only shows, but it works too. It is the Alpha Male, and you will never think of a Cybertruck again.

While the aforementioned is a bit cheeky in light of the plight of now a majority of Americans, it none the less is an actual scenario and reflects badly on how materialistic we have all become. C'mon a 200-foot tower with a log periodic, but the two-girlfriend part might be OK.

Caterpillar is an astute business entity that has been around for over 100 years. They would not enter this market segment without a clear view of the market potential and a reasonable expectation of success. Yellow says it all.

When you know stuff, you buy the right stuff.

73's

Pete N6QW

Products to be found.

Since 99% of hams literally no longer scratch build anything anymore this causes the: Gee does someone make a kit for such and such application. Kit building gives you the feel of being a real ham and not just an appliance operator. Kit building while also is a Flash the Cash is less of the unboxing a completed unit from "Chine" and more of a pseudo feel of I built this.

Antenna tuners are a good example and there are a couple of companies that sell fully automatic high power antenna tuners, and many have a hefty Flash the Cash price tag. But what if you wanted a kit as this suggests having the capability but at a lesser price. So, we consulted the House of Bozos (BoJack + Bezos) and found a plethora of low-cost 100-watt automatic and a bevy of kits (mostly QRP) but some rated at 100-watts where the Flash The Cash < $100. 

A $35, 100-Watt Kit from Bozos.

Now if you are in the 1% who wants to homebrew a 3KW automatic unit then you could do it with stepper motors and Arduino code.

So, now you know where to find Automatic Antenna Tuners assembled for less than $100 or basic kits for under $50. That $35 kit just gets you in the door, but to see the fan dancer you need to spend additional $$$ for connectors, a case, a power supply and likely now beyond $100. But you get the extreme satisfaction of saying: "Look Ma, I homebrewed an antenna tuner kit."

Them that know can scratch build a high-power antenna tuner.

73's

Pete N6QW

A Practical Problem.

Here is the problem. You are passing by a garage sale and spot a box full of parts and the price tag says $0.50. In the box is a pretty healthy power transformer rated at 250AC CT at 0.130 amps, two 100Ufd filter caps rated at 600 VDC and a 10 Henry choke rated at 150 milliamps.

You could get quite an array of voltage outputs from these components depending on what configuration you use for the rectifiers.

Three possible configurations include:

1. Full wave rectifier (2 Diodes)

2. Full wave bridge rectifier (4 Diodes) choke input

3. Full wave bridge rectifier (4 Diodes) cap input

Drum roll...

Full wave rectifier ~ 175VDC

Full wave bridge rectifier choke input ~ 225VDC

Full wave bridge rectifier cap input ~ 350VDC

That is quite a spread but while the voltage values would seem to draw our attention there are other factors which would actually directly influence your selection. Invariably many would invoke the best looking with the biggest boobs criteria (350 VDC) but fail to look at voltage sag, ripple voltage content and current availability. 

The full wave bridge with a choke input has better voltage regulation (less sag), less ripple voltage at full current versus than the Capacitor input form. So, the highest voltage configuration may not be optimum for your application. This requires you to look beyond the size of the boobs.

Not looked at is another configuration and that is the voltage doubler circuit as found in many Heathkit supplies (HP23). That 250 VAC and two caps can be made to look like 700VDC... but not at full current. 

With an eye toward those who think math the voltages in some of the forms is involved with the number 2, its square root, divided or multiplied.

In the case of the simple full wave rectifier we have the 250 VAC multiplied by 1/(2^.5) = 175 after subtracting the diode junction drops.

The full wave bridge with choke input = 250X.9 = 225. 

The full wave bridge with cap input = 250X1.414 = 350

The Voltage Doubler is 250X2.8 = 700. You can easily see gigantic boobs, terrible voltage sag, high ripple and not full current capability. But it is a cheap way to get high voltage.

So, that 50 cents could be quite a bargain. The only concern is the transformer has a short to ground, the caps are at End of Life, and the choke is open. There are no free lunches. Kind of like what the majority of Americans did last November. 

Our garage sale bargain is but another example of Flash the Cash.

Them that know can make things go.

73's

Pete N6QW

The Surprises Coming for Ham Radio! More Flash the Cash.

Our hobby started 1st with Spark Gap transmitters and Coherer Detectors using CW. Fast forward through tubes, transistors, AM, SSB, FM and now Satellite, Digital and of course FT-8.

Something hiding in the bushes is Digital Voice and a new mode FreeDV 2.0 which is digital processing of a SSB signal. Take your standard SSB gear and add the free software FreeDV 2.0 and you are in the mode of pulling your hair out. A snippet from their website...

I saw that there was a demo of this mode as far back as 2018 at a RSGB convention, so this mode has been around for 7 or 8 years. I heard about it yesterday. This Digital Voice Mode is yet another omen of contests and operating overtaking homebrewing anything. Some will read this as an assault on purely hardware defined radios as computers are involved and it is just that. 

My crystal ball suggests this mode will soon be fitted with functionality and software so that your Smart Phone is now a  FreeDV transceiver. All the pieces (or most of) are there, and it just takes someone to link the LEGO Blocks.

FreeDV 2.0 Control Panel

I fired up my Hermes Lite 2.0 and downloaded the free software and got nowhere, but then again, I didn't read the manual. When I hit the PTT button on the screen I could see my transmitted signal on their control panel, so the Hermes Lite 2.0 is being controlled by the Software.

The Bandwidth is less than the 6 kHz often seen with the high end SDR's and supposedly the digitization of the SSB improves the signal in and out. (I am stating to you more than I really actually know.)

It was invented by hams, and the Far East radio manufacturers are financially supporting its development as this will eventually show up as an operating mode on rigs like a future IC7300 MK3. 

This is likely not something you build but takes advantage of already owned rigs and applying open-source free software and this "Good Buddy" results in a new mode of operation. One desirable feature is that you can click a link and automatically see who is on what band and whether they are just listening or actually operating. One watering hole seems to be on 20M at 14.236MHz. 

The above video is a demo of FreeDV on 14.236MHz. It must be in a stealth mode... nothing heard or seen.

Try This One.

I have used the QUISK SDR software for many years and in the last 10 years noted a button on their dashboard marked FreeDV. I never knew what that was.

If you have a plain old SSB transceiver then you will need some sort of interface wiring to the computer and likely a 2nd sound card installed in your computer. For those whose rig is controlled by SDR software some of that wiring exists in the set up for the SDR.

Alert, Alert, there is a Waters and Stanton (a major radio dealer in the UK) you tube video covering the IC7300 MarkII that now has an advertised price and a potential for Christmas delivery. Despite all the improvements and new features like a CW reader, HDMI port and USB C Port and improved hardware, the price point is not a far from a plain, now 9-year-old IC7300. The presenter used great finesse in stating the obvious, with the attractive price of the Mark II, the used market for the original IC7300's will take a downward hit. That affects 100,000 radios as that is the number of IC7300's that have been sold so far.

You better get to know as you will not get to go. 

73's

Pete N6QW