SolderSmoke Daily News

DSB Homebrew from Macedonia -- Sasho Z33ST

2026-04-11T07:55:00.000-04:00

This is a really nice DSB transceiver in progress. Below you see the modules, above you see how the modules will fit onto the board.

DOUBLE sideband is a mode too often dismissed by potential builders. Sasho shows that it is indeed a practical and relatively simple way to get on phone. Sasho has been using these rigs on Parks On The Air operations.

The modular approach is admirable.

Sasho writes:

Hello Bill,
This is a DSB radio design by R0AHZ using NE612 chip as mixer on receive and transmit.
Audio amp is LM386.
Frequency generation is by arduino nano and si5351
RF power amp consists of 2n3553 or any npn eqivalent as pre drive and BD139 as final. Power is about 1 to 2 watts max. I use it together with my power amp and I measure about 40 watts on tx.
Here is a link of me making a QSO wih it.
https://youtu.be/0GKlVfAPgV0?si=KstoJ64kyWRpE-up
73 de Z33ST

Thanks Sasho!

https://www.qrz.com/db/Z33ST

Sasho on POTA

SolderSmoke Homebrew Direct Conversion Receiver Hall of Fame Update: 129 Completed, 122 + 7 Honorable Mentions: (As of April 11, 2026, 0852Z)

2026-04-11T05:14:00.000-04:00

Marian SP9DEL'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.

As of April 11, 2026 0852Z:

So far Total Receivers Built: 129. 122 plus 7 honorable mentions. Total Count: 129. Receivers built in 19 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 (Canada)

KI5SRY Mark -- Gears on PTO screw

KA1MUQ Frying pan receiver

AA1N Adam

ZL1AUN Aaron -- Using SSB transmitter -- (New Zealand)

W8UC Never before homebrewed.

VK4PG Phil -- Nice case, "really pleased"

G7LQX Working well, video of CW and SSB. -- (England)

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. -- (Scotland)

KF8BOG Jim: A long struggle, but success.

Chris Wales Fantastic video. -- (Wales)

YD9BAX Wayan! Homebrew transformer! (Indonesia)

N0NQD Jeff

WN3F Roy -- Made new stickers!

AB5XQ Bill
KB7ZUT Andy
AA1OF Jer

VictorKees Holland (Netherlands)
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 (Australia)
LU2VJM Juan in Argentina -- (Argentina)
K1OA Scott "Most fun in 50 years"
KC9DLM Ben -- Had EFHW problems
PH2LB Lex Yellow, Glue Stick -- (Netherlands)

AI6WR David
G6GEV Dave (It was a blast!) (England)
KC1ONM Wayne MakerLabs NH
KB1OIQ Andy MakerLabs NH
KA1PQK Jay MakerLabs NH
W1TKO Mike MakerLabs NH
K5KHK Karl
SM0TPW Mikael -- (Sweden)
KI7LKB Brian (coat hanger tube)
M6CRD Chris (England)

W2DAB Dave in NYC
W4JYK Wes of VWS
KA4CDN Mike of VWS
M7EFO Adrian
VK5RC Rob (Australia)
KD8KHP Dave
VK1CHW Chris (Australia)
KA0PHJ Brian
W0IT Louis
W1PJE Phil

W2AEW Alan
KN6FVK John (Barkhausen-Be-Gone Spray)
VU2JXN Ramakrishnan -- (India)
AA0MS Doug
9V1/KM7ABZ Paul -- (Singapore)
VK2BLQ Stephen -- (Australia)
N3FJZ Rick
Daniel VE5DLD -- (Canada)
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 (India)

W1DSP Rick

WD4CFN Steve

KM5Z Mike

KF5DAN Dan

Fritz Fritz

N9OK Joe

WA5DSS Bill

K0GDB Grant

G0JNR Shane Glow-in-Dark Coil Form

KK7BCO Tobias

K2BVR Bob

Robert Sutton

K5YFO Dave (Texas)

KD4PBJ Chris

KN4GAH Chris -- EE perspective

F1GMA Philippe -- (France)

W2TEF Todd

EI9ITB Karl -- (Ireland)

VU2TUM Puneit Singh (India)

AA7EE Dave Richards

KI5VIR Jay

CT7AXD Graham -- Promoted from Honorable Mention! (Portugal)

G3MOT Josh (England)

KW4H Steve

NJ7V Charlie (RedSummit)

N2ETZ Denny

AB9LM James

W9XT Gary

G0PJT Alex

KF8FZZ Tyler

N7HPR Steve (Instructor) (N7HPR Group)

Clark (N7HPR Group)

KQ4ZHO Kurt (N7HPR Group)

KQ4OBR Brian (N7HPR Group)

KR4CUF Justin (N7HPR Group)

Amanda (N7HPR Group)

David (N7HPR Group)

KM4AED Jamey (N7HPR Group)

KN4MVH Larry (N7HPR Group)

N5GVW Dick (N7HPR Group)

W7KAL Kal

KC9LFP Joe

SP9DEL Marian (Poland)

LB8VA Ivar (Norway)

-------------------------
Honorable Mentions:

*AA7U Steve No PTO

*VK7IAN Ian -- No Manhattan boards -- (Tasmania)

*KC1FSZ Bruce's build on a PC board

* DL1AJG Andreas -- (Germany)

* Matthew Student of DL1AJG

* Arash Student of DL1AJG

*KA4KXX Walter -- FB 20 Meter version

Dean KK4DAS and Pete N6QW Talk to the River City (Sacramento, Ca.) Radio Club about the 40 meter Direct Conversion Receiver

2026-04-10T09:49:00.000-04:00

On April 7, 2026 Dean and Pete spoke to the River City Radio Club about the 40 meter Direct Conversion Receiver project (see above). Great job guys!

Thanks to Carol KP4MD for the invitation.

ANOTHER AMAZING Homebrew Station -- This one from Belgium -- ON1MWS

2026-04-09T05:44:00.004-04:00

Those large "steering wheels" on the regen rig caught my attention, and I'm glad they did, because they led me to the sites of Danny ON1MWS.

https://www.qsl.net/on1mws/

https://www.qrz.com/db/ON1MWS

Danny writes on his QRZ page:

I'm especially interested in homebrewing my own station. everything from the power supply to the antenna is scratch-build. I have no commercial ham gear, nor do I use pre-fabricated kits or DDS chips.

My gear is a toy compared to a modern station. And it will never even come remotely close to commercial gear. However, the journey to learn how radio circuits work, improve the station and add capabilities over the years has been satisfying. R&D as amusement.

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

FB Danny! Thanks for the rigs and web sites. 73 Bill N2CQR

A really AMAZING Homebrew Station in Brunei

2026-04-08T11:11:00.003-04:00

Didier is F5NPV but he is V85MPV in Brunei for a few years. Check out his amazing QRZ page:

https://www.qrz.com/db/V85NPV

Are There Really Photons on the Signals from, say, a 20 meter Dipole?

2026-04-07T05:59:00.005-04:00

This line from the Hack-A-Day article got me: "Everything on the electromagnetic spectrum has some properties of both waves and particles, but it’s difficult to imagine a radio wave, for example, behaving like a particle."

It is indeed difficlut (at least for me!) to imagine this, especially when we think of the operation of that dipole using waves (not particles).

I really like Jeroen's channel and his approach. Note him waking up, obviously thinking about this question.

Thanks Jeroen, and thanks Hack-A-Day!

U.S. Administration Supports Ham Radio Homebrew

2026-04-01T04:56:00.003-04:00

In a decision that puzzled many analysts, the Federal Communications Commission has come out with a new policy that seems to support the at home construction ("homebrew") of amateur radio equipment. The commission outlined a series of new requirements (see below) that, collectively, seem intended to breathe new life into what many considered a dying art.

Commission spokesman Brian Cox tied the move to recent efforts by the Administration to bring industry back to the United States: "For too long we have stood by and watched foreign manufacturers take larger and larger portions of the electronics market in the United States. Part of this seems to be the unwillingness of many Americans to do what their grandfathers did and actually build their own electronic equipment. These steps are intended to help reverse that trend." Greene's comments may have been undercut by the fact that they were sent from his FCC-provided Iphone (which allegedly was not homebrewed in the USA) and then disseminated via Tik-Tok.

Sources in the Administration also point to recent tariff moves by the government that will have the effect of removing the incentive of cheap foreign-made equipment. "Just wait until those 1000 percent tariffs kick in. You can almost feel those soldering irons warming up!"

Collectively, this initiative seems tied to the political effort known as MAGA. An anonymous White House spokesman explained: "First there was MAGA (calling for a return to GREATNESS). Then came MAHA (HEALTH!). Now we see MASA: MAKE AMERICA SOLDER AGAIN. We think this will be a real winner. There will be so much winning, American hams will soon get tired of winning."

The emphasis, a spokesman explained, will be on DOMESTIC production of radio equipment. "We see the Michigan Mighty Mite as a good example. I mean it just oozes domesticity! MICHIGAN! Why can't we go back to the day when millions of MMM rigs dotted our fruited plains, and people happily conversed via Morse Code using homemade transmitters? Well we can. And dammit we will, whether people like it or not!"

Construction techniques will also be closely regulated, and the naming of these techniques has become an issue: "We like the 'Manhattan' style of construction, but the name is too, well, too 'New York City.' So we are re-naming the technique: From now on it will be known as the 'Mississippi Technique.' We also discovered that all of the Crazy Glue used in the Manhattan -- I mean Mississippi -- Technique comes from overseas. So from now on, only good-old Elmer's Glue can be used. MASA!"

In a related move, the FCC announced that henceforth, only American Morse will be permitted in the United States. The use of International Morse Code will be banned, and masked ICE agents will destroy any equipment found to be using it. "I mean, we invented it right? So when did we go all 'woke globalist international'? Enough of that." It is hoped that this move will reduce the number of radio contacts with foreigners, something the FCC finds "highly woke suspicious." "Americans should be talking only to other Americans, right? " An exception seems to have been made for one country: contacts with Russia will be allowed to continue. No explanation for this exception was provided.

Tracy Kidder, author of Soul of the New Machine, dies at age 80

2026-03-31T13:52:00.001-04:00

He was a great writer. His books are inspirational. Thank you Tracy Kidder.

Obit:

https://www.nytimes.com/2026/03/25/books/tracy-kidder-dead.html?unlocked_article_code=1.XVA.hssv.-OA5DxfI4WPv&smid=url-share

SolderSmoke Blog Posts about Tracy Kidder and his books:

https://soldersmoke.blogspot.com/search?q=Tracy+Kidder

The Green Hornet -- My Visual and 10 meter Beacon from the Dominican Republic

2026-03-25T10:03:00.008-04:00

This all started a LONG time ago when I built a "Lil Slugger" CW transmitter, designed by Doug DeMaw. The schematic appears below -- it appears in both the W1FB Design Notebook, and his QRP Notebook.

Last year I decided to put it on the air from the Dominican Republic. Mike WN2A sent me a programmed PIC chip to key the beacon. I just connected the output of the keyer to the base of the Lil Sluggers keying transistor. This transistor just switched the transmitter's driver transistor on and off.

In the course of messing with this device (and trying to get it to work with a 2 meter beacon) I managed to release smoke from Mike's keyer. Fortunately, Mike had sent the schematic and I was able to tell that it was probably just the PNP transistor at the very end of the keyer circuit. I have some 2N3906s on hand. I replaced the suspect part and Bob was my Uncle. I consider this a "good repair" -- I had to identify the fault, and then replace the part to make the device work.

Then came the fun part. The visual part. I used the keying transistor from the Lil Slugger to drive a super bright green LED from LighthouseLEDs. I had in my DR junk box the parabolic mirror from an old car spotlight (the kind you'd plug into the cigarette lighter). That mirror became the mount for the LED. Before I got the thing going this year, I had to remove some of the window coating that keeps the UV out of the house. Unfortunately it was also keeping some of my beacon's photons IN. It had to go. I used my wife'd hair dryer to take the coating off. As you can see, the visual beacon is now really bright. So far, only one neighbor has noticed the green flashing light. So far, we have heard from no ships at sea. But we are hopeful. Pete N6QW warns of possible cruise missiles. I am prepared to live dangerously.

This video shows the set up from inside the shack, during the daytime:

The ten meter beacon has been doing well and is showing up on the Reverse Beacon Netwok (K1RA and NU4F). I will improve the antenna and this should strengthen the signal even further.

SDR vs. HDR -- Are analog hams Troglodytes, stuck in a rut, resistant to change, and all that ?

2026-03-24T18:50:00.003-04:00

The above paragraphs appeared in a very good ham radio club magazine. I had some comments on it which I shared with the author and the editor. In light of our recent discussion of the ARRL Clean Signal Initiative, I thought that it would be useful for me to post these comments here.

I think the author misses an important point: The ability of radio amateurs to homebrew their equipment. I know from experience that it is difficult to homebrew traditional analog SSB equipment
-- I am running analog SSB gear from two separate
locations. But here is the key: With traditional analog gear, homebrewing of the gear can be done. Not so with SDR gear.

Sure, hams can do their own software (but usually this is limited to the software experts). I suppose that AI will let people vibe code their own SDR software, but I suspect that most hams will not do this. Even if they did, software development is a very different activity than is homebrewing of analog hardware.

And as for the hardware, I suspect that we are rapidly approaching the point where this will come down to the placement of two (maybe one!) chips in their sockets. One ADC chip, one FPGA chip (programmed by an FPGA expert) and you are essentially done. Again, you are talking about a device that is radically different from a homebrew SSB analog transceiver. I can build an analog SSB transceiver, I really can't build an SDR transceiver.

I have problems with your claims that SDR is inherently more sensitive than traditional analog rigs. Maybe if you go FT8, but not with SSB. As for selectivity, well some of my rigs have homebrew 10 pole crystal filters. The skirts are very nearly vertical.

Finally, related to all of the above, is the commercial/SDR vs. homebrew/analog issue. If we go down this supposedly superior path, all of the rigs used by "amateur" radio operators will be commercially produced. They will be much like the Iphone in my pocket. And amateurs will have as much of an emotional connection to their "rigs" as I do to my Iphone: ZERO.

The article portrays the users of analog gear as old Troglodytes, resistant to technological change. I just don't think this is accurate. Some of us stick to the older analog gear because it is possible to really understand it, and it is possible to really homebrew it. That, I think, is very valuable.

73 Bill Hi7/N2CQR

G-QRP 2025 G2NJ Trophy

2026-03-23T10:21:00.003-04:00

Thanks to G-QRP for selecting us for this prestigious award. This was for our efforts with the SolderSmoke Direct Conversion Receiver.

The ARRL's 2025 Technical Service Award

2026-03-22T13:03:27.344-04:00

The ARRL's "Clean Signal Initiative" -- Does the ARRL Now ASSUME all Transmitters are Manufactured?

2026-03-21T05:54:53.349-04:00

Will, KI4POV alerted us to this -- we've been reading about it for some time. I have always found it worrisome. Here is why: ARRL -- an organization that has its roots in HOMEBREW radio -- seems to be adopting standards that will discourage radio homebrewing. They seem to be pushing for transmitter cleanliness standards that can only be met by advanced, SDR-based, manufactured radios.

I realize that the number of hams who actually build their own SSB gear is shockingly small. Many of us eschew SDR architecture because of its complexity, and because much of it is based on CPU, ADC, and FPGA chips that, well, are manufactured by some distant company, and are NOT homebrewed by us.

I am sure the Iphone in my pocket will meet or exceed the ARRL's Clean Signal Initiative standards. But should this be the model that radio amateurs follow? Is the ARRL -- with its badges! -- moving us closer to FCC standards that will -- in effect -- outlaw things like non-SDR architecture, LC oscillators, and homebrew crystal filters? What about older boatanchor gear? Will the new standards be applied to my Hallicrafters HT-37? Or my DX-100? And what about the homebrew CW gear that is sometimes (all too rarely) heard on the ham bands? These "rigs" (they deserve that title) often use (GASP!) tubes. It seems that under the ARRL's CSI, all of these kinds of rigs will have to go. They will all have to be replaced by properly-badged SDR mystery boxes from overseas manufacturers. Get out your credit cards guys, and put away the soldering irons! A new day has dawned, brought to you by the ARRL CSI!

I can hear the howls of complaint already: Bill is such a trolodyte. He is opppsed to progress. He is in favor of dirty signals. He would have been with those defiantly proclaiming "SPARK FOREVER!" He refuses to embrace progress and get with the CSI program.

Well, if the new program does -- in effect -- lead to the prohibition of simple, homebrew circuitry by radio AMATEURS -- if it does move us ever closer to the day when the only way to meet purity standards is via a manufactured SDR mystery box, I am opposed to that. I prefer homebrew rigs.

Here is the latest on this ARRL initiative:

https://www.arrl.org/files/file/QST%20Binaries/April%202026/Spatta%20Clean%20Signal%20Initiative.pdf

Space Hints from the Dominican Republic in 1994

2026-03-21T04:58:22.070-04:00

Check out the article in the link below. I too got a QSL from RS-10!

https://www.gadgeteer.us/SPAHINT.HTM

The 2 meter portion of the Ray-Gun appears below. I still have the elements.

Solar Powered Drone from South Africa

2026-03-20T09:04:31.935-04:00

I've been flying a DJI 4K Mini drone here in the Dominican Republic, so I am interested in the whole drone thing. The technology involved is pretty amazing, with many of the drones featuring GPS tracking systems, onboard compasses, and inertial (gyroscopic) stabilizers. This in addition to high resolution, stabilized cameras, look-down landing cameras, and obstacle avoidance systems. Oh yea, if you lose sight of the 249 gram drone, you can just hit the HOME button and it will miraculously fly to its start point and land. Wow.

This fellow in Capetown takes things quite a bit further. I like his solar-powered drone. He has a really cool workshop. There is something for everyone here: He uses 3-D printing, carbon fibers, and computer assisted design tools. And he does a lot of good-old soldering. I really like his portable wind meter. I will get one for this very windy location in the Dominican Republic.

Audio Amplifier Stage Template and Handout: SolderSmoke Direct Conversion Receiver by N7HPR

2026-03-12T06:09:00.003-04:00

Above is Steve N7HPR's template for the audio amplifier board, the board that gave a lot of people a lot of trouble. But it SHOULD have caused a lot of trouble! It is the only gain stage in the receiver -- it provides at least 80 db of gain. It deliberately uses no feedback -- we did it this way to keep the circuit simple. So if you let too much of the output find its way to the input, this amplifier will turn into an oscillator. Then you will have to tame it. And almost all builders did. This was a valuable lesson: All amplifiers aspire to be oscillators. They have to be denied the Barkhausen criteria.

Above we see the placement of Rex's Me pads, and the transformer. (Note that Steve DOES ground one of the output pads.) I think that Steve's layout was really good -- it sounds like they did not have a lot of the feedback and motorboating problems that were reported by others. This is a good reminder of the importance of careful layout.

Here is Steve's handout:

Steve's messages have caused me to reflect a bit on this project. I will try to write about this in the days ahead.

Thanks Steve. And thanks to all the builders.

SolderSmoke Direct Conversion Receiver: TOROIDS! Steve N7HPR's Handouts on the BP Filter and the Mixer/Diplexer

2026-03-11T05:47:00.004-04:00

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

Winding the trifilar toroids was the hardest part of building the mixer board, and with the high school students, I admit to chickening out. Instead I prepared about 17 of them using a batch from Hyderabad (wound by the seamstresses!) that Farhan left me. Here is how we did it: https://soldersmoke.blogspot.com/2023/02/progress-report-high-school-students_25.html Steve's use of wires of different colors is a good idea. It helps to keep track of the different wires.

We often hear that winding toroids is a show-stopper for many would-be homebrewers. This should not be the case. Winding the coils is not difficult.

The Diplexer came from Roy Lewellan W7EL's optimized QRP Transceiver. Dean and I were struggling with the suppression of signal from Radio Marti on 7335 kHz. When we added Roy's diplexer, it seemed to help knock down Radio Marti.

We too used the NanoVNA to tune the BP filter. I remember this as one of the more pleasing moments for the students.

SolderSmoke Direct Conversion Receiver-- N7HPR Handout #1 -- The VFO

2026-03-10T10:14:00.003-04:00

I like the way Steve N7HPR did this: First, that he had a working receiver on display to serve as a prototype. Second, that he asked the students to come up with their own Manhattan board designs and third, he provided templates that would allow them to properly place their Me Pads.

We did some of these things with the high school students. We definitely had a prototype on display, and they looked at it a lot. We did ask them to deisgn their own Manhattan boards -- as I recall, the response to this was uneven at best. The templates are a good idea that we did not try with our group build.

One big advantage of building the VFO first -- the students get something of the Michigan Mighty Mite sensation. They have successfully built a source of RF, a transmitter! We had one of the students move around the room with his oscillator (battery powered) turning it on and off as he listened to the tones from a DX-390 receiver. This is very similar to the demonstration that Marconi did with the very first radios.

More tomorrow.

Thanks again Steve.

Steve N7HPR Describes the Group Build of 10 SolderSmoke Direct Conversion Receivers

2026-03-09T17:28:00.005-04:00

Group Build of the SolderSmoke Direct Conversion Receiver Challenge

By Steven Bible, N7HPR

Andrew Johnson Amateur Radio Club and Greene County Makers, Greene County Tennessee

The main goal for the group build is hands-on learning. Each of the students are working on their amateur license. Three are working on their Technician, one General, and the remainder on their Extra. The extra exam has a great deal of detailed technical knowledge and the SolderSmoke Direct Conversion Receiver Challenge is a great vehicle for teaching many of these technical details.

Several in the group have experience soldering thru-hole components on a printed circuit board. However, Manhattan style construction was new to them. It would add a valuable skill to their toolbox. The question, from an instructor’s point of view, was how to ease them into this skill before taking on a much larger project? The answer was to first build a smaller project to introduce the students to this unique construction style. I chose Allen Wolke’s W2AEW YouTube video on building a buffered Colpitts crystal oscillator. The added benefit was teaching the oscillator questions on the amateur exams.

#123: Build a crystal oscillator from schematic thru prototype construction and

testing – DIY [https://www.youtube.com/watch?v=blalAktxFoI]

In the video, Allen shows how to identify the nodes on a schematic and use them as the

pads on the PCB. From this I came up with a teaching method where the students study

the schematic and sketch on a handout how they plan to assemble the board. I

designed and 3D printed a template for the student to trace onto the PCB with a pencil.

They would superglue MeSqares onto the squares of the template, and the circles were

suggestions of where to ground components to the PCB. This gave them the mental

exercise to reason how to take a schematic and turn it into a prototype. Building the

oscillator was an excellent introduction and helped lead the students into the larger

DCR Challenge.

PCB Template. Students sketch the template onto the PCB.

Over the course of eight weeks of 2-hour classes, the students built the four blocks of

the Direct Conversion Receiver. I designed and laser cut a baseboard from 1/8-inch (3

mm) Baltic Burch plywood where the students could mount the four blocks of the

receiver. This provided the students some structure in assembling the receiver.

We started with the VFO block first. The most challenging thing was winding the PTO

form. But everyone managed. Other challenges were poor solder joints and missing

connections, which were easy to remedy. They became excellent teaching points.

I also noticed that students would look at the (what I called) the prototype Direct

Conversion Receiver that I built to show everyone what it would look like in the end. As

it turned out, this was a valuable part of the group build. Students would take photos of

the prototype so that they could gain a better understanding of the construction of the

receiver.

As students completed their VFO, I would test it using an oscilloscope demonstrating to

them what and how an oscilloscope works and the signals coming from their VFO.

The second block was the Band Pass Filter. This block had easier transformers to wind

compared to the mixer. This allowed a gentler introduction to toroid winding. To aid in

the identification of the windings, I purchased red and green enameled wire that had a

poly-coat that was easy to remove using a blob of solder on the soldering iron. Overall,

this was a simple block for the students to assemble. As students completed their Band

Pass Filter, I connected it to a nanoVNA and allowed them to tune the filter. Another

great teaching moment introducing them to filters and vector network analyzers (VNA),

all if which are on the General and Extra exams.

The third block to be assembled was the Mixer. This had a little more challenging

transformer with the trifler windings. I purchased enameled wire in three colors: copper,

red, and green. The copper-colored wire was coated with enamel which required

scraping to remove. The red and green was the poly-coating the students were familiar

with from building the Band Pass Filter.

The three colors allowed the students to identify the primary (indicated with a dot on the

schematic) and secondary sides. The schematic showed the location of the colors and

the MeSquares they were to be attached to. This alleviated much of the confusion that

can occur with connecting trifler windings (see DCR Mixer Handout.docx).

The forth block was to assemble the Audio Amplifier. By this time the students have

developed their knowledge and skills to assemble the one block that had the most

components. Assembly went smoothly; however, we would have the occasional

misplaced component, bad solder joint, etc. This was the case throughout the build, but

they were welcomed as excellent teaching moments.

When the entire Direct Conversion Receiver was assembled, we would test them first

using a tinySA in signal generator mode and inject a 7.1 MHz carrier. We would tune the

PTO to tune down to 7.0 MHz and up to 7.3 MHz. We had to add an inductance in

series with the PTO to accomplish this range. This took some trial and error. There was

some troubleshooting to be done to find an error or two. Finally, we connected the

receivers to a loop antenna and listened to on-the-air signals. It was not the best

antenna setup, but it gave the students confidence that their receivers were working.

The amateurs in the group took theirs home and hooked them up to their station

antennas to listen further. Each reported good reception.

The Soldersmoke Direct Conversion Receiver Challenge was an excellent group

project. The students learned a great deal from the hands-on experience. W2AEW’s

buffered Colpitts crystal oscillator video was perfect for introducing Manhattan style

construction. Creating a kit of parts, 3D printed templates, handouts, and laser cut base

gave structure to the group build and minimized construction errors. Having a fully built

receiver (that I called the prototype) for students to refer to proved extremely valuable.

Building as a group provided an encouraging environment where the students would

assist each other and share teaching moments (what to do, what not to do). Finally,

there were many teaching moments that helped solidify knowledge and skills and there

were many direct references to the questions on the Technician, General, and Extra

exams. The goal of the group build was met!

Many thanks to the SolderSmoke team for an excellent project!

73, Steve N7HPR

Thanks Steve! More to follow -- Steve's handouts on the construction of each stage are really great.

Stay tuned!

SolderSmoke Homebrew Direct Conversion Receiver Hall of Fame Update: 128 Completed, 121 + 7 Honorable Mentions: (As of April 5, 2026, 0833Z)

2026-03-06T11:39:00.007-05:00

N7HPR's Group

One of the 10 Receivers They Built

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.

As of April 5, 2026 0833Z:

So far Total Receivers Built: 128. 121 plus 7 honorable mentions. Total Count: 128. Receivers built in 18 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 -- New Zealand

W8UC Never before homebrewed.

VK4PG Phil -- Nice case, "really pleased"

G7LQX Working well, video of CW and SSB. -- England

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. -- Scotland

KF8BOG Jim: A long struggle, but success.

Chris Wales Fantastic video. -- Wales

YD9BAX Wayan! Homebrew transformer! Indonesia

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 -- Argentina
K1OA Scott "Most fun in 50 years"
KC9DLM Ben -- Had EFHW problems
PH2LB Lex Yellow, Glue Stick -- Netherlands

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 -- Sweden
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 -- India
AA0MS Doug
9V1/KM7ABZ Paul -- Singapore
VK2BLQ Stephen -- Australia
N3FJZ Rick
Daniel VE5DLD -- Canada
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

KM5Z Mike

KF5DAN Dan

Fritz Fritz

N9OK Joe

WA5DSS Bill

K0GDB Grant

G0JNR Shane Glow-in-Dark Coil Form

KK7BCO Tobias

K2BVR Bob

Robert Sutton

K5YFO Dave (Texas)

KD4PBJ Chris

KN4GAH Chris -- EE perspective

F1GMA Philippe -- France

W2TEF Todd

EI9ITB Karl -- Ireland

VU2TUM Puneit Singh

AA7EE Dave Richards

KI5VIR Jay

CT7AXD Graham -- Promoted from Honorable Mention!

G3MOT Josh

KW4H Steve

NJ7V Charlie (RedSummit)

N2ETZ Denny

AB9LM James

W9XT Gary

G0PJT Alex

KF8FZZ Tyler

N7HPR Steve (Instructor) (N7HPR Group)

Clark (N7HPR Group)

KQ4ZHO Kurt (N7HPR Group)

KQ4OBR Brian (N7HPR Group)

KR4CUF Justin (N7HPR Group)

Amanda (N7HPR Group)

David (N7HPR Group)

KM4AED Jamey (N7HPR Group)

KN4MVH Larry (N7HPR Group)

N5GVW Dick (N7HPR Group)

W7KAL Kal

KC9LFP Joe

SP9DEL Marian

-------------------------
Honorable Mentions:

*AA7U Steve No PTO

*VK7IAN Ian -- No Manhattan boards -- Tasmania

*KC1FSZ Bruce's build on a PC board

* DL1AJG Andreas -- Germany

* Matthew Student of DL1AJG

* Arash Student of DL1AJG

*KA4KXX Walter -- FB 20 Meter version

Rex Harper on the 50th Anniversary of the Tuna Tin 2 -- DONATIONS NEEDED!

2026-03-03T06:56:00.003-05:00

I was really pleased to see Rex Harper W1REX on a special edition of the RedSummitRF video podcast:

https://www.youtube.com/watch?v=SUQE4OvkAtU

Rex provides a lot a great background info on the Tuna Tin 2. We are approaching the 50th Anniversary of the publication in QST of the Doug DeMaw article that launched the TTT revolution. Rex has the original TTT in his possession, and is organizing a 50th Anniversary tour. We can only hope that much Mojo will be dispensed.

I built one in a real tuna can: https://soldersmoke.blogspot.com/2014/05/fdim-midnight-mojo-ceremony-tuna-tin-2.html I still have the board!

And above you can see Rex allowing the Mojo of the original TTT to flow into my homebrew 17 meter BITX (2014). Rex and Charlie talked about this ceremony in the video cast. Very cool.

Rex is making available a 50th Anniversay edition kit of the Tuna Tin 2. Get yours here:

https://www.qrpme.com/?p=product&id=50A

Also, Rex needs some help in financing a Tuna Tin 2 world tour. YOU CAN HELP! No need to limit your donation to 1 dollar. Donate here! https://www.qrpme.com/?p=product&id=WWT

Thanks Rex, thanks Charlie!

Stuart Brand

2026-02-25T09:39:00.001-05:00

A couple days after I announce that I don't want to help Jeff Bezos make any more money, it might come as a surprise that I am linking to this article about a guy who seems to LIKE Bezos (and also Musk!). But I do like Stuart Brand. I have a copy of the Whole Earth Catalog, and it had a lot of good ham radio content in it:

https://soldersmoke.blogspot.com/search?q=Whole+Earth+Catalog

Anyway, here is the article. I found it very interesting.

https://www.theguardian.com/technology/2026/feb/25/tech-legend-stewart-brand-on-musk-bezos-and-his-extraordinary-life-we-dont-need-to-passively-accept-our-fate

SolderSmoke Podcast 263: DR-PR, UM, DCRX, SKN, Design, PSSST, W7ZOI, FT-101, HW32A, VK, HST, AMP, MAILBAG

2026-02-23T10:49:00.002-05:00

Pete Juliano N6QW

February 23, 2026

SolderSmoke Podcast #263 is available for download:

Audio: http://soldersmoke.com/soldersmoke263.mp3

Video: https://www.youtube.com/watch?v=Fn164glxQ6s

Opening

May 26, 2014, coming up on 12 years! That was the 1^st podcast where Pete N6QW was interviewed by Bill in Podcast #161, which means 102 podcasts ago. 12 Years of Julian-ismo. Thanks Pete!

What to build? Question faced by VWS Makers Group and by Charlie of RedSummit RF. Regen? Test Gear? Simple oscillator?

But did you DESIGN it yourself? What does that even really mean? Barrie Gilbert in Jim Williams' book: https://soldersmoke.blogspot.com/2025/12/homebrew-you-say-but-did-you-design-it.html

Grayson KJ7UM on a podcast -- Make it your own way. Copper Clad and Glue! Manhattan style! "BUILD SOMETHING!: Tube testers not necessary. OK to call thermatrons "vacuum tubes." No ruling on calling them "valves" yet.

Pete:

-- When hams were hams -- Turning a Heath monobander into a tribander

-- Simple SSB

-- W7ZOI rigs

-- The Yaesu FT-101

SHAMELESS COMMERCE DIVISION: Mostly DIY RF! Patreon! But no more Amazon. We do not want to help Bezos make more money. Even if this will cost us. So please, consider a donation or a Patreon sponsorship instead. But no more Amazon through SolderSmoke.

Bill:

-- Dominican Republic to Puerto Rico on 2 meters -- status report.

-- Working Australia on 20 meter SSB in the morning.

-- The SpiderWeb net.

-- The Hubble Space Telescope -- an old friend

-- One contact on Straight Key Night (Dean reminded me). I worked NB1U on 20 meters with QCX from KD4EBM.

Dean:

-- The University of Michigan ant the Direct Conversion receiver project.

-- Boxing up the amplifier. A tale of woe. Identifying oscillations. A QSO with the Dominican Republic: https://soldersmoke.blogspot.com/2026/02/a-qso-with-dean-kk4das-northern.html

Travails with other homebrew gear... Trying to find a working transceiver.

AI assisted repair of Bitx40 PA in my Mythbuster

VWS club station update, tendency of Flex and other SDR makers to not release even basic technical information.

MAILBAG:

Ian VK3MO Huge antennas, big signal, friendship with WA3O https://soldersmoke.blogspot.com/2025/11/vk3mo-and-wa3o-brotherhood-of-ham-radio.html

Bob KD4EBM 2 meter propagation info

Todd K7TFC -- Mostly DIY RF

Mike K6STR Worked Pete on 40, building for CW and SSB on 2 meters

Grayson KJ7UM German Avionics, MMM Origin. Old Steampunk Homebrew rig: https://soldersmoke.blogspot.com/2025/12/a-very-interesting-old-steam-punk.html

Phil W1PJE Forrest Mims III Mims's sad denial on climate change.

Ciprian YO2DXE Heard the SAQ Alternator see: https://soldersmoke.blogspot.com/2025/12/alexanderson-alternator-on-172-khz.html

Tom NS6T: Very useful azimuth map with grey lines: https://ns6t.net/AzShadowMap/experimental.html

Walter KA4KXX -- 20 meter Direct Conversion Receiver. FB Walter!

WN2A Mike Dos Equis man is BACK! https://soldersmoke.blogspot.com/2026/01/hes-back-dos-equis-man-most-interesting.html

KB4HG Rhett: On USB on the Old Military Radio Net with a PRC-74. Want one!

Saw the Hubble Space Telescope Again this Morning

2026-02-15T05:49:00.004-05:00

Skies were brightening at 0626 local. And there were a lot of clouds. But HST appeared right on schedule, and I saw it between the clouds as it passed overhed. There should be even better passes in the morning during the next two days.

The Mahbood Radio Service Company of Hyderabad, India

2026-02-13T10:16:00.000-05:00

Our friend Farhan sent this today. It is really beautiful and captures very well the magic of radio. Thanks Farhan. and thanks too to Mohammad Moinuddin of the Mahbood Radio Service.

“Before television and smartphones, Hyderabad listened to the world through radios. And in those days, my father ensured that the city stayed tuned in.

My father, the late Shaik Mahboob, founded Mahboob Radio Service in 1933 in Dabeerpura. At a time when radio was still a luxury, he began selling and repairing sets for households across the Old City. In 1948, after Hyderabad’s accession to the Indian Union, he shifted the shop to its present location in Chatta Bazar, where it continues to stand even today.

Interestingly, he did not begin with radios. In the late 1920s, he was involved in the PVC pipes trade. But as radio technology slowly entered Indian homes, he recognised its future and transitioned into the business of radio sales and repairs. That decision shaped our family’s destiny.

Like my father, my brother and I grew up surrounded by valves, wires, and wooden cabinets. After school, we would sit beside him, carefully observing how he handled brands like Murphy, Philips, Bush, Marconi, and later Sony. Those were the golden years of radio in Hyderabad.

Among our customers were prominent families of the city. We even serviced radio sets for the palace of the last Nizam, Mir Osman Ali Khan. Payments would arrive in a sealed lifafa — a gesture that felt both formal and special. In those days, radio wasn’t just entertainment; it was how people heard news, music, cricket commentary, and the world beyond their homes.

Over time, technology changed. Transistors replaced valve sets. Then came television. Now, smartphones have taken over. Radio sets are no longer common in households. Many shops that once repaired them have shut down.

My brother, who shared this passion with me, is no more. But I continue to open the shutters of our shop every morning. People still travel from different parts of the country — some carrying radios that are older than me — hoping to restore a memory. I repair them not just as machines, but as pieces of someone’s past.

Today, in my late seventies, I sit at the same wooden table where I learned this craft as a boy. Because this is not merely a business, it is continuity. It is a responsibility.

On World Radio Day, my only wish is that people remember the warmth of gathering around a radio set. I also hope today’s radio jockeys continue to create thoughtful and meaningful programming. Because radio is not outdated — it is timeless. As long as I am here, Mahboob Radio Service will remain tuned in.”

– Mohammad Moinuddin, Mahboob Radio Service