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Thursday, December 18, 2025
Happy Birthday to Pete Juliano N6QW
Tuesday, December 16, 2025
Arduino, Adafruit, Open Source, Qualcomm, and all that
This is not really my thing, but the changes to 60 meter rules recently caused me to crack open some older Arduino/Si5351 and AD9850 VFOs, so maybe this was my thing...
Still, all of this chatter kind of disappears once you embrace analog LC VFOs. But here is a good article about all of this:
https://thenewstack.io/adafruit-arduinos-rules-are-incompatible-with-open-source/
Friday, December 12, 2025
15 kHz of 60 meters FINALLY Liberated! But Watch Out for the 9.15 Watt ERP Limit
Here's a reminder of how long this took: When Bob KD4EBM alerted me to the ARRL announcement that 15 kHz of the 60 meter band had been "liberated," I turned to my blog and found articles talking about this possible change way back in 2017. Oh well, better late than never.
Here is the ARRL announcement:
Here are a couple of references from the SolderSmoke blog and one from the BITX Hacks blog in which Don ND6T shifts the BITX40 module's bandpass filter to 60 meters.
https://soldersmoke.blogspot.com/2017/03/channelized-bitx-60-with-five-channels.html
https://soldersmoke.blogspot.com/2017/03/bitx-sixty-with-three-short-videos.html
https://bitxhacks.blogspot.com/2017/02/cap-stack-hack-putting-bitx40-on-60.html
I reached into my junk box this morning and found the digital VFO I was using way back in 2017. I may turn to Don again for help in getting the VFO segment to work.
I got a chuckle about the FCC power limit: 9.15 watts ERP. Wow, such precision! Can you imagine the FCC breaking down a radio amateurs shack door after, perhaps, measuring 9.16 watts ERP? BUSTED!
Thursday, December 11, 2025
Homebrew Radio from Southern India
Tuesday, December 9, 2025
"Homebrew you say? But did you DESIGN it yourself?"
That is a question we get fairly regularly when we tell the other fellow that our rig is homebrew. I often get the feeling that the question stems from a certain insecurity -- the guy who asks it may feel a bit insecure because the "rig" he is running is completely commercial and his only role in its production was to flash a credit card number.
But lately I have been reading through Jim Williams' wonderful book "Analog Circuit Design -- Art, Science, and Personalities" and I can see that there may be something to this question.
It was the chapter by Barrie Gilbert that made me think more about this. Barrie is the legendary designer for whom the Gilbert Cell is named. This circuit is at the heart of the NE602 chip that many of us used to build our first "Neophyte" receivers and other homebrew rigs. Barrie's chapter is entitled "Where do Little Circuits Come From." Uh oh.
Barrie grew up in the post-war United Kingdom. He father had been killed in a German bombing raid. As a kid, he built crystal radios and, with his brother, "shortwave sets" on softwood bases. He used a TRF receiver that employed Manhattan-style construction. Barrie, it seemed, was one of us.
But then, he suddenly seemed more advanced. He wrote:
"Later, I began to build some receivers of my own but stubbornly refused to use circuits published in the top magazines of the day, Practical Wireless and Wireless World. Whether they worked as well or not they had to be "originals" otherwise, where was the satisfaction? I learned by my mistakes but grew to trust what I acquiered in this way: it was 100% mine, not a replication or mere validation of someone else's inventiveness."
Wow, that is certainly hardcore. I will note, however, that in getting back to the the question about whether I have "designed" the rig myself, I have NEVER had the questioner come back to say that HIS rig was homebrewed from HIS OWN original design. Never. Not once.
And I will note that building a rig from the schematic is an enormous challenge. It is not easy. It is not the mere replication of someone else's inventiveness. Anyone who thinks it is easy should try to homebrew a simple direct conversion receiver. They will discover that it is NOT easy.
I guess this comes down to what we mean by "homebrew." I prefer to stick to the old ham radio meaning of the term: It is homebrew if it was built at home, even if it is built from a schematic done by someone else. When Jean Shepherd built his Heising Modulator, was he working off a schematic from a ham radio magazine? He almost certainly was. But he gathered the parts, laid out the chassis, and put the circuit together. Most importantly, when trouble cropped up, he was able to step in and make the needed corrections. Was his modulator "homebrew?" Of course it was. Did he design it himself? No, his name was not Heising!
More than 100 people built our SolderSmoke Direct Conversion Receiver. We resisted pressure to turn this project into a kit. The folks who built it worked off schematics that we had prepared. They gathered the parts and built their own circuit boards, Manhattan style. They struggled to get the whole thing to work, to make sure the VFO was on the right frequency and at the right level, that the AF amplifier was not oscillating. Were these receivers "homebrew?" Of course they were.
Jim Williams warned that Analog Circuit Design was "A wierd book." He strongly discouraged collaboration between the authors, and noted that this would probably result in "a somewhat discordant book." We see that discord in the hardcore position taken by Barrie Gilbert. Many of the other designers seem to take a more flexible, less austere position. Some even seem to downplay the role of mathematics.
I think Barrie had a right to be proud of his fundamentalism. But not all of us are capable of that. Writing in Jim Williams' book, Samuel Wilensky sums it up nicely:
"I classify analog designers into one of two categories. There are those who do truly original work, and these I consider the artists of our profession. These individuals, as in most fields, are very rare. Then there are the rest of us, who are indeed creative, but do it by building on the present base of knowledge."
Some Great Analog Pictures from MIT Building 20 and other Analog Locations
Here is a picture of Jim Williams taken through a Tektronix oscilloscope camera. I never used one of these things, but Dean KK4DAS did. Here are the details of the shot:
I took this great photo of Jim Williams with a Tek scope camera sometime around 1977 or so. There was no digital (or analog) manipulation. It was a simple double exposure. I first shot a scope waveform, then just to see what would happen, I pulled the camera off the scope, stuck it Jim’s face and snapped another shot before pulling the film. I never expected it to look this good….a view from inside the oscilloscope!
Here is the collection of pictures that this 'scope shot came from:
https://lensprojects.com/analog-history/
Thanks to Len Sherman for the pictures. On his site you will see, among other things, the upside down Christmas Tree of dead parts, and Bob Pease's Volkswagen Beetle.
More info on MIT's Building 20:
https://en.wikipedia.org/wiki/Building_20
Saturday, December 6, 2025
SSTV! Slow Scan Television
https://www.qsl.net/on6mu/rxsstv.htm
Time for something completely different. As a kid, I lusted after the ROBOT SSTV systems that were advertised in QST. Yesterday, on a lark, I downloaded this program, tuned my Mythbuster transceiver to 14.230 MHz, and put the podcast microphone in front of the speaker. BOOM! SSTV signals started pouring in. The program automatically set the kind of SSTV format that was coming in, so there was no need for me to try to figure out if it was Scottie 1 or Martin 1 or whatever. I've done this before, but this program made it easier. The invention of SSTV by Copthorne MacDonald (another GREAT ham radio name!) is really interesting:
https://soldersmoke.blogspot.com/2011/07/early-days-of-sstv-by-copthorne.html
I note that the first article in QST appeared in the month of my birth, and the FCC decided to allow SSTV in the phone bands when I was 10 years old.
Here are some signals received yesterday at N2CQR:
An Analog Life -- A Video about Jim Williams
Friday, December 5, 2025
Dave Richards AA7EE Builds and Documents the SolderSmoke Direct Conversion Receiver
https://aa7ee.wordpress.com/2025/12/04/the-soldersmoke-direct-conversion-receiver/
Thanks Dave!
Thursday, December 4, 2025
Jim Williams -- Analog Man -- Book Review: "Analog Circuit Design -- Art, Science, and Personalities"
Wednesday, December 3, 2025
Tuesday, December 2, 2025
Grote Reber -- W9GFZ -- Radio Astonomy Pioneer, Homebrew Hero
Second, Grote Reber's mother was also the teacher of Edwin Hubble. Hubble was the guy who discovered that there were OTHER GALAXIES in the universe, and that they were all moving away from each other. That was a BIG discovery! Later, Grote's mom also had her son in her class. Both students were from Wheaton, Illinois.
Lest there be any doubt about Grote's dedication to radio, consider the following. (Much of the following comes from Wikipedia. https://en.wikipedia.org/wiki/Grote_Reber)
When he learned of Karl Jansky's work in 1933,[5][6][7] Grote Reber decided this was the field he wanted to work in, and applied to Bell Labs, where Jansky was working.
Pioneer of Radio astronomy

In the summer of 1937, Reber decided to build his own radio telescope in his back yard in Wheaton, Illinois. Reber's radio telescope was considerably more advanced than Jansky's, and consisted of a parabolic sheet metal dish 9 meters in diameter, focusing to a radio receiver 8 meters above the dish. The entire assembly was mounted on a tilting stand, allowing it to be pointed in various directions, though not turned. The telescope was completed in September 1937.[8][9]
Here is a really great article from Sky and Telescope magazine (July 1988) about Reber's homebrew radio telescope:
http://jump.cv.nrao.edu/dbtw-wpd/Textbase/Documents/grncr071988a.pdf
He was limited by the size of locally available 2X4 lumber. Neighbors thought he was trying to control the weather or to bring down enemy aircraft. Between Wheaton and the NRAO site in West Virginia, Reber's telescope spent some time at the National Bureau of Standards site in Sterling, Virginia. I was in Sterling just yesterday. I wonder if there is a plaque or something noting the telesccope's stay in that town. I note that at age 15, Reber had built a ham radio transceiver.
AND THEN HE MOVED TO TASMANIA
He did this because of propagation and low noise conditions. (This reminds me of how we sometimes said that very few people have actually said the words, "And then we moved to the Azores.")
Starting in 1951, he received generous support from the Research Corporation in New York, and moved to Hawaii.[12] In the 1950s, he wanted to return to active studies but much of the field was already filled with very large and expensive instruments. Instead he turned to a field that was being largely ignored, that of medium frequency (hectometre) radio signals in the 0.5–3 MHz range, around the AM broadcast bands. However, signals with frequencies below 30 MHz are reflected by an ionized layer in the Earth's atmosphere called the ionosphere. In 1954, Reber moved to Tasmania,[12] the southernmost state of Australia, where he worked with Bill Ellis at the University of Tasmania.[13] There, on very cold, long, winter nights the ionosphere would, after many hours shielded from the Sun's radiation by the bulk of the Earth, 'quieten' and de-ionize, allowing the longer radio waves into his antenna array. Reber described this as being a "fortuitous situation". Tasmania also offered low levels of man-made radio noise, which permitted reception of the faint signals from outer space.
His Homebrew House in Tasmania
In the 1960s, he had an array of dipoles set up on the sheep grazing property of Dennistoun, about 7.5 km (5 miles) northeast of the town of Bothwell, Tasmania, where he lived in a house of his own design and construction he decided to build after he purchased a job lot of coach bolts at a local auction. He imported 4x8 douglas fir beams directly from a sawmill in Oregon, and then high technology double glazed window panes, also from the US. The bolts held the house together. The window panes formed a north facing passive solar wall, heating mat black painted, dimpled copper sheets, from which the warmed air rose by convection. The interior walls were lined with reflective rippled aluminium foil. The house was so well thermally insulated that the oven in the kitchen was nearly unusable because the heat from it, unable to escape, would raise the temperature of the room to over 50 °C (120 °F). His house was never completely finished. It was meant to have a passive heat storage device, in the form of a thermally insulated pit full of dolerite rocks, underneath, but although his mind was sharp, his body started to fail him in his later years, and he was never able to move the rocks. He was fascinated by mirrors and had at least one in every room.
To Canada -- And a Rejection of the Big Bang
The same July 1988 issue of Sky and Telescope magazine has a good historical vignette of Reber, with a focus on his actvities in Canada late in life (click on the image below). Reber had big doubts about the big bang. Unfortunately this seemed to spill over into scorn and ridicule for those who -- well -- believed in the big bang. We see this at the end of the article. Oh well, even great people sometimes get cranky.
Three cheers for Grote Reber.