Kevin K3IY's Beautiful FB SolderSmoke Direct Conversion Receiver: "An amazing experience... A milestone for me..."

Kevin's receiver was beautifully built. And it sounds great.  Congratulations Kevin, and welcome to the Hall of Fame. 

Kevin writes: 

This was my first “real” homebrew project.  I’ve built a few kits and toyed with some basic circuits, but this is a milestone for me.  It wasn’t without some troubles but what an amazing experience.  I couldn’t get my oscillator to work and the issue was I tried to make due with two 680pF ceramic caps.  I took Dean’s advice to stick with the 330pF silver mica’s and I found my signal.  At this point I also broke down and bought an oscilloscope.  I now plan to do some mod’s and eventually build a TR switch and pair it with a transmitter.  I can’t thank Bill and Dean enough for making this an obtainable goal.  Kevin, K3IY

Kevin's receiver on CW (above) and SSB (below). 

He's thinking about his receiver

Chuck N4AVC's FB SolderSmoke Direct Conversion Receiver: "I enjoyed the build and testing."

Chuck N4AVC's use of the frequency counter in his digital multimeter is pretty cool and innovative. And it is nice to have yet another receiver in Virginia; he is down in the Richmond area.  And of course the Sharpie callsign tattoos on the wooden board are really nice. 

Chuck writes:  

Completed!!! For Pete: "She ain't pretty, but she sure can cook!". Thanks Bill and Dean, I enjoyed the build and testing. It's funny, the audio oscillates on an older 9v battery, but is clean on the 9.5v bench supply. Going to put Bill's mod on the inductor to make tuning a little finer and spread the boards out a little more. I used the double sided boards I had and there is some interaction between the boards.

Congratulations Chuck! Welcome to the Hall of Fame!

Simplicity, Presence, Mods, and Direct Conversion Receivers

Over on the Discord server that we set up for the SolderSmoke Challenge project.  One of the guys who succeeded in building the receiver (kudos to him!) commented that, for some reason, his receiver didn't sound good on SSB.  I was kind of surprised by this, because usually we hear the opposite:  that direct conversion receivers sound GREAT on phone.  In fact, this may be the origin of the term "presence" when used to describe the audio quality of DC receivers.  So I sent this note on the issue: 

Sounds like you are on the right track in wanting to understand the circuitry .   I would just point out that even experienced users of commercial SSB radios are usually impressed by the sound quality of simple direct conversion receivers like this one.  This is the origin of the term "presence"  -- Doug DeMaw used this word when describing the experience of listening to Wes Hayward's 1968 direct conversion receiver.  He said it made the guy from the distant station sound as if he were "present" in the room with the receiver!  From an article about this event:  "This was the epiphany, the moment when Doug realized that solid-state technology had produce a new way to build a simple receiver. Doug tuned the receiver higher in the band and found some SSB. Again it was like nothing he had ever heard. It was as if the voice came from the same room. Doug used the term presence in his description."  So you should not have diminished expectations for this simple receiver.    Realize that Wes's receiver was even simpler than ours!    I don't feel a need to defend this design, but will point out that these receiver can sound great if used properly.   Here is a recording of one of these receivers in action in December 2024:  https://www.youtube.com/watch?v=JSI7YDJGAos  And this one: https://soldersmoke.blogspot.com/2024/12/listening-to-40-meters-on-dc-receiver.html  Mods are great, but remember that you CAN diminish the simplicity and thus the "presence" of these receivers by strapping on a lot of unnecessary  features:  filters, amplifiers, Digital VFOs, frequency counters, etc.  especially if these mods are put in there to address shortcomings that don't really exist.  73  Bill N2CQR

What do you folks think of all this?  

BTW, you too can get involved in the project by visiting our Discord server.   Just go to Discord and set up (it is easy) you own server.  Then use this logon to get to the SolderSmoke Discord server: 

Join the discussion - SolderSmoke Discord Server:

https://discord.gg/Fu6B7yGxx2

Paul WA1MAC GETS DOWN TO BRASS TACKS with his FB GLUE STICK SolderSmoke Direct Conversion Receiver

 

Wow, look at that beautiful build of the SolderSmoke Direct Conversion Receiver.  We haven't received a "proof of life" video from Paul yet, but we trust that his receiver does in fact work.  Paul has some heavy care-giver responsibilities that keep him in his home.  We do not want to complicate  his life by asking for outside antennas or videos.  

We are also not going to complicate Paul's life my insisting that he build it our way.  First, his life is already complicated enough, and second, the innovations he introduced are really cool.  The use of brass tacks and conducive copper tape is really ingenious.  And the glue stick has brought him to the Joy of Oscillation (JOO).  In fact the glue stick has given him JOVO -- the Joy of Variable Oscillation.  FB Paul.  

Paul writes: 

Hi guys

I've been gettin down to brass tack here at the mac-shack!  Fits in nicely within my new caregiver role.

Been having a ball with the brass thumbtack breadboarding from SPRAT on your DC Receiver challenge!

Gluestick PTO, check, alive with the joy of oscillation!

BPF, check (need to tune once I find the nano VNA here somewhere)

DBM and diplexer, check, there was room on the board left over so I cheated and snuck the BPF on that board too

3 BJT audio amp with transformer, check, alive and passes the finger test, loudly!

Since I currently have no 40m antenna here guess it's time to finally put that active antenna I've been meaning to build............Any how thanks for all the fun and hair pulling, oh wait, I'm already bald!

 

73

 

Paul  WA1MAC, get it the mac-shack  :-)

JOVO! 

Glue Stick! 

Brass tacks! 

Congratulations Paul!  Welcome to the Hall of Fame!  

HCJB is now in Western Australia. In "The Kimberly." And VK6JMS can use their antenna.

I grew up listening to HCJB's shortwave broadcasts from Quito, Ecuador.  Fast forward to the present:  This week I have had two radio contacts with Nic VK6JMS.   His callsign indicates Western Australia.  I assumed he was in the Perth area, but no, he is in the northern part of Western Australia, in the area known as The Kimberly.  Look on the map for the place called Kununurra.  That is where he is.  

Here is Nic VK6JMS's QRZ page: https://www.qrz.com/db/VK6JMS  He has access to some really fantastic antennas.  In his page he refers to them at TCI antennas.  I looked them up: 

 A TCI dipole array refers to a specific type of antenna system designed and manufactured by SPX Communication Technologies, a company formerly known as TCI. These arrays are typically used for high-frequency (HF) radio broadcasting and communications, and they are known for their ability to achieve wide bandwidths and efficient radiation patterns. 

https://www.antenna.be/tci-611.pdf

https://www.antenna.be/tci-613.pdf

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

These antennas are used for the SW broadcasts: 

Since 2003, Reach Beyond (formerly HCJB) has been transmitting from our Broadcast Facility in the Kimberley, in far north Western Australia, to the Asia Pacific region through shortwave radio, and currently broadcasts programs in 25 languages.

Founded in 1931 as radio station HCJB in Quito, Ecuador, Reach Beyond is now a global, partnership-driven ministry. Many people know us as the shortwave ministry that originated in Ecuador which went on to establish hospitals and medical clinics in Quito and Shell. Today the visionary “madness” of our founder Clarence Jones and his band of missionary pioneers lives on around the world. 

Here in Australia, Reach Beyond carries on that vision through its radio broadcast ministry. Our shortwave facility is uniquely placed in Australia to deliver powerful messages of hope to remote and isolated communities throughout the Asia Pacific region.  https://www.reachbeyond.org.au/on-air/

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

One thing I noticed about Nic VK6JMS's signal:  there seemed to be a latency delay between when I turned the conversation over to him, and when he began to transmit.  I wonder if the Icom RS-BA1 remote station software that he is using might explain this latency. Any ideas on this?

Ted KN4ZXG's FB SolderSmoke Direct Conversion receiver: "This project is the greatest gift to homebrewing..."

There it is, a thing of beauty.  The best part is that Ted built this receiver himself.  That is something that most hams NEVER do. 

Ted writes: 

This project is the greatest gift to homebrewing since I got interested in radio nearly a decade ago. Lot's of great projects out there but most go into a mysterious black hole of obsolete parts like the NE612 mixer that's hard to get, or even the LM386, which is plentiful but not as cool as this amp. Everything's divided neatly on it's own board and explained. The builder has wiggle room on the layout and ways to test each module whether that's with nice or budget equipment. Not only did I learn a ton about each stage, but also about making RF probes and making use of my modest but super useful equipment like the Nanovna. Although there were no mysteries, it all comes together to make magic. If you know stuff, you can do stuff! Thanks again de KN4ZXG, Ted.

While he has some great plans for modifications and improvements, at this point I think Ted should follow Farhan's advice and spend some time just listening to the receiver that he has built. Direct conversion receivers sound especially good. It is as if they are closer to the ether.

Here are some clips of Ted's receiver in action:

 

Congratulations Ted.  Welcome to the Hall of Fame.  

G0UPL at Dayton: SSB for the QMX, and Thoughts on Homebrewing

 

Click on the diagram for a better view.

Listen to the interview here: 

http://soldersmoke.com/G0UPL at Dayton 2025.mp3

I think this is what Grayson was talking about when he said that Hans is a genius, and that his SSB project for the QMX was very complicated.  On his website Hans says as much:  "This is a very complex project."  Indeed it is.  Just take a look at the bloc diagram above.  This is not for the faint of heart.  In this interview, he talks about a full year of intense work on SSB for the QMX.  Wow. 

I think Hans makes some good points on why we still homebrew.  I liked his fish analogy:  we can buy all the fish we want at the supermarket, but people still go fishing.  Why? Because they like fishing.  

I'm not too sure about "the IKEA effect."  He seems to be saying that people derive homebrew-like satisfaction from assembling IKEA furniture.  Well, maybe some people do, but I think this is a long way from what we would consider true scratch-built homebrew.  Dean KK4DAS, for example, recently observed that he assembled two IKEA tables, but that this assembly does NOT make him a carpenter.  This is related to our discussion about the differences between ham radio kits and true homebrew:  IKEA flat packs are like the kits.  I think Hans is right about the pride and satisfaction that people get from building their own radio gear.  

Thanks to Hans GOUPL and to Bob W8SX for doing this interview. 

Mitch NK3H's FB SolderSmoke Direct Conversion Receiver -- "Incredibly satisfying!"

Wow, Mitch NK3H has built a really nice receiver. (He says it is not pretty, but those of us who have built one or who are in the process know that it looks great.) The SSB really sounds good also. 

Mitch writes: 

It's not pretty but it works! Incredibly satisfying. In answer to the questions, (1) though I 'd built a few small Manhattan style boards (e.g., Michigan Mighty Mite) this was more complicated. I've been using W1REX's island cutter to create isolated areas on the copper clad board, rather than pasting on pieces of circuit board. But the islands are a little small for as many as four connections on one island, as in most of the transistor bases. Inevitably a component lead would inadvertently contact the ground plane and all bets were off. Tracking down the shorts was challenging. (2) Once I got to the audio amplifier board I carefully laid out all of the components before starting to solder. But as I finished each stage and was ready for the next, I always seemed to be missing a resistor or two. I'd search the desk and the floor -- very frustrating. Turns out the speaker magnet was collecting and hiding the missing resistors. Lesson learned. (3) Next I'm hoping to build a transceiver. Still looking for the right project, probably a little more digital than this wonderful DCR.

Mitch obviously learned a lot during this project.  I had similar experiences with pads on the same level as the surrounding board -- I found that the 1 or 2 mm of elevation provided by the Manhattan pads prevented a lot of inadvertent shorts to ground.  And I too "lost" (temporarily) a lot of components to the magnet in the speaker.  

Good luck with the next projects Mitch.  With the Michigan Mighty Mite and the DCR under your belt you are ready to go.  Maybe a Double Sideband transmitter to go with the DCR? Or, as you said, perhaps something more digital.  There is a lot of good ham experience with the Si5351 digital VFOs.  Or maybe even an SDR rig.  

Thanks Mitch.  Congratulations and welcome to the Hall of Fame. 

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

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

Grayson Evans KJ7UM Interview at Four Days in May at the Dayton Hamvention 2025

 

LISTEN TO THE INTERVIEW HERE: 

http://soldersmoke.com/KJ7UM at Dayton 2025.mp3

Grayson said quite a lot in this short 4 minute interview: 

-- At FDIM he was selling his wonderful book "Hollow State Design for the Radio Amateur."  Buy one here: https://www.ermag.com/product-category/books/ 

-- Grayson was also selling a Thermatron version of our beloved Michigan Mighty Mite transmitter.  It is crystal controlled for the 40 meter band, but the Color Burst Liberation Army approves! Here is a wonderful video on this rig:

https://soldersmoke.blogspot.com/2024/09/excellent-new-video-from-grayson-kj7um.html

And be sure to watch Grayson's excellent course on Thermatron Homebrewing: 

https://soldersmoke.blogspot.com/2024/02/grayson-evans-kj7um-video-on.html

-- Asked why someone should build with tubes when so much good solid state stuff is available, Grayson makes some especially excellent points:  The solid state gear is often filled with mysterious little black boxes -- we often don't really know what goes on in there.  Thermatron construction provides a break from complicated SDR nonsense "that is not really radio."  That last comment will generate some criticism, but not from here.  I think Grayson is right,  He earlier expressed admiration for complex circuitry, but he also rightly defends simple, understandable rigs.  

Here are Grayson's Technical Documents (a real treasure trove):  https://kj7um.wordpress.com/

Three cheers for Grayson.  And thanks to Bob Crane W8SX for doing this interview.  

Bill K7WXW's FB SolderSmoke Direct Conversion Receiver

This is a very nice build.  Bill K7WXW fought a long battle to get this receiver working, and -- more importantly -- to understand why it is working.   

Bill writes: 

The cycle of design, sim, build, debug, update, repeat can teach you a lot.

FB Bill.  Welcome to the Hall of Fame! 

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

Hall of Fame: The SolderSmoke Direct Conversion Receiver -- 80 Completed Receivers, 7 Honorable Mentions, Built in 15 Countries -- Many More Receivers Being Built.

WA1MAC'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 June 18, 2025  1049Z:

So far 80 completed receivers, with 7 honorable mentions.  Receivers built in 15 countries.   

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

W1PJE             Phil

W2AEW           Alan

KN6FVK          John (Barkhausen-Be-Gone Spray) 

VU2JXN           Ramakrishnan

AA0MS            Doug 

9V1/KM7ABZ   Paul in Singapore

VK2BLQ          Stephen

N3FJZ              Rick

Daniel               VE5DLD

Student 1          Student of VE5DLD

Student 2          Student of VE5DLD

Student 3         Student of VE5DLD

K7WXW          Bill 

NK3H               Mitch

KN4ZXG         Ted

WA1MAC        Paul

N4AVC             Chuck 

K3IY                 Kevin

N6ASD             Ashish in Bangalore

W1DSP             Rick

WD4CFN         Steve

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

Honorable Mentions: 

*AA7U            Steve No PTO

*VK7IAN        Ian -- No Manhattan boards 

*KC1FSZ        Bruce's build on a PC board

*CT7AXD       Graham -- different AF amp

* DL1AJG      Andreas 

* Matthew      Student of DL1AJG

* Arash           Student of DL1AJG 

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

Candidates for the Hall of Fame: 

SA5RJS              Rasmus

KA9TII               James

AA7FO              Chuck 

VA3ZOT           Tony  Surface Mount -- Honorable Mention? 

KM5Z              Mike Yancey

AB2XT             John (Done, just need the video)

KO7M              Jeff (Piper Cub)

KD4PBJ           Chris

VU2TUM         Puneit Singh

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

Daniel VE5DLD's FOUR FB Saskatchewan SolderSmoke Direct Conversion Receivers

Daniel VE5DLD is a teacher in Regina, Saskatchewan, Canada.  Back in early 2023 several lucky students joined him in building the SolderSmoke Direct Conversion receiver.  We had asked people to build the receiver -- we wanted to test the design before asking the local high school students to build it.  Daniel and his students came through for us, and ended up having far more success than we did.  Congratulations Daniel!  Welcome to the Hall of Fame. 

Daniel wrote: 

Hi Bill!  Yes, I had my own DC Receiver that I use every so often for fun and 3 built by my students.  All working.  We didn't get any video because we just finished the school year and the kids left, but I've kept in contact with them and they told me they have been able to receive signals from their homes.  The kids developed excellent troubleshooting skills gained large amounts of confidence in their ability to fix things.  Over the next year, my students told about fixing their gaming consoles and fixing problems in their parent's electronics.  They are certainly no longer afraid of opening something up to see what is going on!  And that's what makes me the most happy!  Yeah, you can just recognize myself and only mention that 3 students were able to build DC receivers.

And yes, the Michigan Mighty Mite was a fantastic gateway to home brewing!

Thanks for thinking of me and my students!

73

Daniel D.

VE5DLD

On June 19, 2023,  Daniel wrote: 

We got everything going and all 3 students now have receivers capable of inhaling RF.  We 3D printed some knobs and hot glued them.  We took one outside but didn't hear any signals.  Mid afternoon is not good for 40m.  We will try again later this week and I'll bring my KX3 to make sure there is a single for them to listen.  This issue on that last radio was an improperly installed J310.  The angle is was installed hid the problem well!  Here are a few pictures of the completed rigs. 

Back in 2015, Daniel built a Michigan Mighty Mite.  I was pleased to be reminded that I had sent him the crystal.  Go CBLA!  For more info on Daniel's transmitter see: 

https://soldersmoke.blogspot.com/2015/10/saskatchewan-mighty-mite-video.html

Thanks Daniel! 73  

___________________________

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