Dave KD8KHP's FB SolderSmoke Direct Conversion Receiver

Very cool build by Dave.  That PTO coil form looks great. And the receiver sounds especially good on sideband.  FB.  Congratulations Dave! 

Dave writes: 

This was a fun build, and I learned something.

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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

Rob VK5RC's FB SolderSmoke Direct Conversion Receiver. MDS?

Rob VK5RC has completed his SolderSmoke direct conversion receiver.  Congratulations Rob.  And it is good to know what we have a Medical Doctor among our builders -- this adds prestige and expertise to the project. 

Rob measures a Minimum Discernible Signal at -95 dbm.  I think that is kind of weak performance.  Much depends, of course, on how you define "descernible."  Some books say you need a 10 db increase in audio.  Others say you just need to be able to tell there is a signal there.  I have gone with the latter definition and have measured MDS of around -120 dbm.   I wonder why there is such a difference in measured MDS.  

In any case, it is great to see Rob's receiver inhaling all of that great Australian SSB (see video above).  Thanks Rob, and congratulations.  

Adrian M7EFO's FB SolderSmoke Direct Conversion Receiver

Adrian has completed a very FB direct conversion receiver.  Really nice work. It is especially pleasing to see that Adrian is a member of GQRP.  FB Adrian. SSB above, CW in the video below.  I think that China Radio International signal would be a good early target for your tinkering and mods.  We fought a similar battle against Radio Marti.  

Adrian writes:  

Did it!!! It Works.! Receives CW, SSB,FT8. Awesome. Thanks Bill. Thanks Dean. It was fun. Now for the tinkering and modifications.

CW too. As an added bonus it picks up China Radio International radio whether I like it or not.😄

Hello. I live in East Barnet a suburb of London, UK.

I work as an electronic technician and tech support for a small company. 

My rig is a Xeigu G90 with a home made dipole cut for 20 metres and 40 metres and run QRP at 5-10 watts, 5 watts FT8, I'll save the kilowatts for boiling the kettle!  I'm using an old PC server power supply. 

The shack computer is a Raspberry Pi3 Raspberry Pi400 (Stolen Borrowed from my daughter). I am surprised at how well my set up works. Sometimes.

I am a member of the GQRP club and have started building some kits and homebrew in the Manhattan style. 

Currently studying for my UK Intermediate licence with Bath Based Distance Learning.

The Copasteic Flow Blog -- German UHF Mobile CW Through a Geostationary Satellite, Agent Sonya's Homebrewing, More

It is always good to be reminded that someone out there is listening and reading,  especially when it is nice folks like Hamilton and his family. These are the people who built the TouCans rig that was (is?) suspended above San Francisco at the center of a dipole antenna.  

Following posts on the SolderSmoke blog, Hamilton has been monitoring the CW activites of a German ham who sends UHF CW signals through the sunroof of his car to the QO-100 satellite in geostationary orbit.  See above.  Very cool.  Listen live to the satellite here: 

https://eshail.batc.org.uk/nb/

Also cool is Hamilton's analysis of Agent Sonya's ability to homebrew a 1930s era CW station that could be used to communiate with Moscow Center.  Hamilton believes she could do it.  I have my doubts.  But the discussion is a lot of fun. 

Check our their blog: 

https://copaseticflow.blogspot.com/

Thanks to Hamilton and his kids! 

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.