A New Distance Record with an ESP-32 Module? Sort of. A cool video from HB9BLA.

 It was nice to watch a video from Andreas again.  And to be reminded of the presence in geostationary orbit of QO-100.  Really sad that we STILL have no equivalent over the United States. 

Andreas engages in a lot of the kind of digital wizardy that I have learned (because of my own shortcomings) to stay away from.  Still, this is a very interesting experiment, with lots of focus on antenna gain and path loss at UHF.  I plan on again listening to QO-100 via the website.  Thank you Andreas!  

SolderSmoke Podcast #259 FCC ban of DC Receivers. Pete and Stickers, Mouse Knob, MHST. DC RX Update. Dean and SDR RX, Mythbuster Transceiver, Frequency Counter. Bill's Shack -- Suburban Renewal, Boatanchor Removal, DJI Drone . MAILBAG

Dean KK4DAS's 20 Meter Transceiver

Video Version: https://www.youtube.com/watch?v=RslKbpBuYDI

Audio Version: http://soldersmoke.com/soldersmoke259.mp3

Reports of FCC action against Direct Conversion receivers. Outrageous!  They are going to prosecute Dean and Bill.  The 85th harmonic was apparently interfereing with Starlink satellites over Melbourne Australia, Bali, New Zealand's North Island, the UK, Sweden, Holland and Argentina. Who knew? 

Here's the question:  How many paragraphs of this post did you read before you realized this was an April 1 thing?  C'mon, please let us know.  Bill falls for one or two every year.  This year he believed that Warren Buffet really had bought Tesla. So, don't feel alone.  Fess up.  

Travelogue:  Pete's trip to Los Olivos.  DMV Real ID Blues.  Going back to San Francisco? Pete, we have some new stickers... 

Pete's Bench:  MHST progress. Raspberry Pi.  VWS.  Transceiver.     K7TFC's Mouse Knob. 

Dean and Bill update on the SolderSmoke Direct Conversion Challenge:  56 receivers built.  And 56 is a lot! Info and especially Dean's videos are still up on the Discord server and on YouTube.  Not to late to build!  All builders should try to encourage at least one other person to build this receiver.  In this way, builders become Elmers and homebrewing can spread.  Others have already done this -- you can do it too!  W4KAC built a second one for a friend.  WZ5M built one, helped a friend do a second, and a third one may be on the way.  MakeIt Labs in Nashua, NH is responsible for 4 DC receivers.  See all the completed receivers here: 

https://soldersmoke.blogspot.com/search/label/DC%20RX%20Hall%20of%20Fame

Once you have the receiver going, start the mods!  Front panels!  Antennas! Better tuning!  Si5351s! DSB transmitters! Tell us about your mods. 

SHAMELESS COMMERCE DIVISION:   Become a Patreon Sponsor!  MostlyDIYRF.  Buy Amazon stuff through the Amazon link on our blog site.  Subscribe to our video YouTube channel. 

Dean's Bench:  SDR Receiver project.  20 meter Mythbuster build (a thing of beauty).  Homebrew Frequency Counter.  Balloons!  

Bill's Bench:  Suburban renewal.  New floor, new paint, got rid of a lot of junk.  New operating table from Husky.  DX-60, DX-40, VF-1, and maybe even the Lafayette HA-600A receiver have to go. Many books and magazines too.   Lightening the load!   But keeping the DX-100, HQ-100, HT-37 and, of course, the Drake 2-B.  Boatanchors station. Beacon operations. 

N2CQR's new operating table

Boatanchor Corner at N2CQR

Bought a new DJI Drone, but will use it in the Dominican Republic (not here!).  And I got my Drone TRUST Certificate. 

Mailbag:  

Dave W2DAB doing Manhattan building on the island of Manhattan!  

Rich K2GJ (ex WA0CGM) -- Nice ham radio memories of his HT-37.  Thanks Rich. 

Wes W4JYK -- A VWS DC receiver. 

A nice note from Farhan VU2ESE. 

Todd K7TFC -- Simple vs. Complex

Paul WA1MAC Gluestick 80 meter QRP

Armand WA1UQO Regen receiver highlighted by AA7EE

Dave AA7EE -- FIGHT BACK AGAINST THE FCC!  Build the DC Receiver! 

Rogier PA1ZZ Many great videos, including one on Heathkit

Bruce KC1FSZ --  Nominated us for ARRL award.  Thanks Bruce. 

Bob KD4EBM--  Looking into Polar Modulation. https://qrp-labs.com/qmxp/ssbbeta.html

Peter VK2EMU -- Thought of Peter when I briefly took down the N2CQR sign he made. 

Victor HI7S -- 46 km away from my place in the DR.  Says I won the lottery...  He is right. 

Jim KI4THC        Got his Extra ticket.  Congratulations Jim. 

Kirk NT0Z    -- On Kits, Hombrew,  and the influence of Russian Homebrewers. 

Were Russian spies taught how to homebrew their own spy radios? 

Rich K2GJ with his 2B, and Heath GR-91

Inside Dean's Transceiver

Agent Sonya -- Did Soviet Spies Really Homebrew Their Rigs?

Ursula Kuczynski (Agent Sonya), 1936.Credit...via Peter Beurton

My recent blog post about the intrepid Soviet hams who homebrewed versions of the UW3DI SSB transceiver led to a comment about early Soviet era overseas intel officers who -- supposedly -- homebrewed their own transmitters and perhaps receivers.  

Here is a New York Times review of the book that mentions the homebrewing by spies:

https://www.nytimes.com/2020/09/15/books/review/agent-sonya-ben-macintyre.html

Here's the Wiki page on Sonya:

https://en.wikipedia.org/wiki/Ursula_Kuczynski

Tony Percy took a look at the homebrew claims:

https://coldspur.com/signal-sonyas-wireless/

Percy seems quite well informed about radio and about how believable Sonya's claims about her radio activities were.  He uses the Morse acronym QRP, talks about Maximum Useable Frequency, discusses antennas and the relative difficulty of building a receiver.  He also talks about the need for crystal controlled transmitters if the QRP transmitter was to have any hope of reaching Moscow Center.  In sum, he thinks the reports of Sonya's radio derring-do are just nonsense.  

I agree with Tony Percy.  I just think it would be impossible to take a newcomer, show them how to scratch-build a radio, send them to a foreign country, have them buy the needed parts, expect them to build the rig and the antenna... oh and learn to use the Morse Code along the way.  I just don't think that is possible.  

Is Tony Percy a ham?  What do you folks think about the plausibility of the claims about Sonya's radio prowess?  

A Homebrew Crystal Filter Shaped Like the Desired Passband -- by Andy KB7ZUT

 

Over on our Discord channel, some of those who have successfully built the SolderSmoke Direct Conversion Receiver are starting to experiment with Double Sideband and even Single Sideband.  Andy KB7ZUT is experimenting with QER filters.  He recently wrote: 

My second attempt at a SSB crystal filter using the QER topology.  I think laying out the crystals to resemble the filter profile you want should help 😏

I think the Radio Gods would be pleased Andy. 

Here is a free invite to our Discord server: 

Join the discussion - SolderSmoke Discord Server:

https://discord.gg/Fu6B7yGxx2

"Seems Like Radio is Here to Stay" -- Old Radio, Radio Magic

The first 12 minutes of this podcast are pretty good.  I think it captures well the wonder of radio -- magic carpets, signals taversing the Himalayas and all that -- but the presentation is kind of confused.  The PRX podcasters keep saying that it was recorded in the 1930s, but then we hear references to the Nuremburg trials and the possibility of sharing the atom bomb. So there is some confusion in the presentation. 

https://podcasts.apple.com/us/podcast/champions-of-old-radio/id453044527?i=1000702716017 

Can anyone find the original recording from the 1930s about the wonder of radio, without the references to things that happened in the late 1940s? 

Thanks to Rogier for sending this to me. 

Norman Corwin

Homebrew vs. Kits -- The influence of Russian Homebrewers

 

Click on the image for a better read. 

Like Kirk, I too was influenced by the Russian and Eastern European homebrewers.  As a kid, every issue of QST seemed to contain (especially in the "How's DX?" column) pictures of intrepid Russian homebrewers seated next to their HOMEBREW stations.  I wanted to be like them. 

When I first launched the Direct Conversion Receiver Challenge, someone decided that it would be better to make the receiver into a kit. He criticized me for deciding to keep this project homebrew. There seemed to be a lack of understanding of the difference. This morning I got an e-mail from Kirk NT0Z. He attached his column from the February 2013 issue of Monitoring Times. I think he captures very well the difference between kits and homebrew. An excerpt from the column appears above. I need to get a portrait of UW3DI to hang above my workbench. Thanks Kirk.

Here is more info on the UW3DI transceiver:

https://www.cqdx.ru/ham/ham-radio-news/the-legendary-diy-russian-uw3di-transceiver/

Use Google Translate on this site: https://uarl.com.ua/bylsluchay/autor/ux0un_vivat_uw3di.html

DJI Drones -- How it All Began (with a shout out to Frederick Terman)

Lots of interesting stuff in this video, including a short clip of non-other-than Frederick Terman, of Stanford University and Silicon Valley.  Like many of you, I have Terman's "Radio Engineer's Handbook" on my shelf. 

The Amazing Technological Development of DJI Drones

Yes, the ability to hover is a really big deal. 

Kalman filtering.  Who knew? 

GPS, compasses, intertial navigation, redundancy.  Great stuff. 

NZ showed DJI that quadcopters were the way to go.  

The importance of brushless motors. 

It is really amazing how quickly quadcopters took over from ordinary helicopters.  The regs in the DC area that prevent us from flying quadcopters here were probably developed BEFORE the quadcopters were developed. 

I still wonder about why we still fly normal helicopters:  Take you hands off the controls of a helicopter and it will soon start to flip and fall.  Take you hands off the controls of a quadcopter and it will just hover in the sky.  When the batteries get low, it will return to the start point and land.    

I have a video taken by my Hanmilt drone on my Patreon channel.   I have already bought a DJI Mini 4K to fly in the DR. 

Mike KA4CDN's Engraved SolderSmoke Direct Conversion Receiver -- Another VWS RX!

Mike KA4CDN is an experienced homebrewer and a member of the Vienna Wireless Society.  He took the SolderSmoke challenge and built the direct conversion receiver.  Congratulations Mike, and welcome to the Hall of Fame!  

Mike writes:

The goal of the project was mainly to test my conversion of my Ender3 3D printer into an engraver for making PC boards. Thank you Bill and Dean for leading the project. It had been a while since my soldering iron was hot on an RF electronics project. It is amazing how fast I get rusty and forget stuff. Now I'm going to pick back up on my crystal filter that I started I think two years ago

 ;-(  Awesome! 

For more information on how you too can build the receiver: 

Join the discussion - SolderSmoke Discord Server:

https://discord.gg/Fu6B7yGxx2

 

Documentation on Hackaday:

https://hackaday.io/project/190327-high-schoolers-build-a-radio-receiver

 

SolderSmoke YouTube channel:

https://www.youtube.com/@soldersmoke

The History of MOSFETs -- Let us Remember the 40673. The IRF510. And others...

Lots of great history explained in this video.  I found myself thinking about our beloved 40673 dual gate MOSFET: 

https://hackaday.com/2016/03/21/the-curse-of-the-40673-zombie-components-that-refuse-to-leave-the-building/ 

And, of course,  about the IRF510.  

Asianometry on MOSFETs, MESFETS, CMOS and Moore

Asianometry does a pretty good job here.  I am sure people will quibble about some of his descriptions of radio, AF, and RF.  But overall, pretty good.  I did see what looked like a direct conversion receiver in his block diagrams, but it was described as a superhet.

I was also struck by what looked like the lack of shielding in the modern cell phones.  Some hams seem to believe that we cannot live without shielding.  But apparently we can.  

I also like how the bloc diagrams have the LO feeding mixers both on the receiver side and on the transmit side.  I realize that you can do this by switching the LO, but I like to feed both mixers at the same time.  

Asianometry talks about the need for inductors in the chips, and how this was often a show-stopper.  This made me think about the Gilbert Cell that we find in our beloved NE-602s.  Wasn't Barry Gilbert trying to create a balanced mixer that would not need coils? 

Finally, there is a nice review of the history of Silicon Labs.  I was hoping to see the Si570 and, of course, the Si5351.  But no, these seem to have come later than the slide used by Asianometry.  

The Hall of Fame -- Completed SolderSmoke Direct Conversion Receivers (So far --- more to come!)

Dean KK4DAS's Receiver

Please let us know if you spot any errors, or if we have inadvertently missed anyone.  Don't worry about being late to the game -- the challenge continues.  All of the info is still available (see below). 

As of April 29, 2025  0942Z:

So far 59 completed receivers, with 4 honorable mentions:  

NE3U (KY4EOD)  Matt 

KQ4AOP       First ham signals ever heard! 

N9TD             Derek

AC3NG          Ryan

VK3TPM       Peter Marks  

W4KAC         Ken 

W4KAC         Ken built a second one! 

N2EPE           Erik

VA3NCA        Wayde    

KI5SRY          Mark -- Gears on PTO screw

 

KA1MUQ       Frying pan receiver

AA1N              Adam

ZL1AUN         Aaron -- Using SSB transmitter

W8UC             Never before homebrewed. 

VK4PG           Phil -- Nice case, "really pleased"

G7LQX           Working well, video of CW and SSB. 

KE2AMP        John     Spring on PTO screw -- great

N9SZ              Steve  nice receiver

KD9NHZ        Piotr  Nice one

KE8ICE          Calvin, Very cool receiver. 

 

WV3V              Jayson!  Got it done!

GM5JDG         Martin.    

KF8BOG          Jim:  A long struggle, but success.  

Chris Wales    Fantastic video.  

YD9BAX        Wayan! Homebrew transformer! 

N0NQD        Jeff 

WN3F              Roy -- Made new stickers! 

AB5XQ            Bill  

KB7ZUT          Andy  

AA1OF            Jer

VictorKees        Holland

KC9OJV           John -- Manhattan-style convert

WZ5M              1, 2 or maybe even 3 receivers!

K1KJW             Jim in Vermont

KC5DI              Dallas -- friend of WZ5M

Gary                 Australian -- Wooden PTO form

LU2VJM          Juan in Argentina

K1OA               Scott "Most fun in 50 years"

KC9DLM         Ben -- Had EFHW problems

PH2LB             Lex  Yellow, Glue Stick

AI6WR             David

G6GEV            Dave (It was a blast!) 

KC1ONM        Wayne  MakerLabs NH

KB1OIQ          Andy    MakerLabs NH

KA1PQK         Jay       MakerLabs NH

W1TKO           Mike    MakerLabs NH

K5KHK            Karl

SM0TPW         Mikael

KI7LKB           Brian (coat hanger tube)

M6CRD            Chris

W2DAB           Dave in NYC

W4JYK            Wes of VWS

KA4CDN          Mike of VWS

M7EFO             Adrian 

VK5RC             Rob

KD8KHP          Dave

VK1CHW         Chris

KA0PHJ           Brian

W0IT                Louis

-------------------------

Honorable Mentions: 

*AA7U            Steve No PTO

*VK7IAN        Ian -- No Manhattan boards 

*KC1FSZ        Bruce's build on a PC board

*CT7AXD       Graham -- different AF amp

-----------------------------------------

Candidates for the Hall of Fame: 

SA5RJS              Rasmus

KA9TII               James

W2AEW             Alan

AA7FO              Chuck 

K7WXW            Bill 

W1PJE               Phil  MIT

VA3ZOT           Tony  Surface Mount -- Honorable Mention? 

KM5Z              Mike Yancey

AB2XT             John (Done, just need the video)

KO7M              Jeff (Piper Cub)

KD4PBJ           Chris

For more information on how you too can build the receiver: 

Join the discussion - SolderSmoke Discord Server:

https://discord.gg/Fu6B7yGxx2

 

Documentation on Hackaday:

https://hackaday.io/project/190327-high-schoolers-build-a-radio-receiver

 

SolderSmoke YouTube channel:

https://www.youtube.com/@soldersmoke