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Wednesday, August 20, 2025

Grant K0GDB's FB SolderSmoke Direct Conversion Receiver

Congratulations to Grant K0GDB on his FB SolderSmoke Direct Conversion receiver.  Welcome to the Hall of Fame Grant! That PTO former is especially FB!  Grant is a relatively new ham, making his smooth construction of this receiver even more admirable. 

Grant writes: 

Proof of life video! Many thanks for the helpful YouTube tutorials, everything went together pretty smoothly.

The windings are actually as close to the specification as I could get them on the nanoVNA. It's been a bit since I built that part, but if memory serves I had one fewer turn and had to do some bunching to get it to read correctly. The main difference in the PTO is that I made the former on a laser cutter from slices of quarter-inch plywood since I don't have a 3d printer. The center cyllinder is actually just rolled up paper.

A Second Aeronautical Mobile Contact with Mike KX4WC/Aeronautical Mobile


August 19, 2025 20 meter SSB in the afternoon. Mike KX4WC/Aeronautical Mobile was enroute to San Juan from Miami, flying through the edges of Hurricane Erin. Also in the QSO was John VY2WW and Mike WA3O. WA3O is a long-time listener to SolderSmoke. He has a water-cooled amplifier and he sent me his Heathkit HW-7 (which I still have).

Mike and I could hear each other through most of his flight.  We were both especially strong when he reached his closest point to my location.  At this point he was about 50 miles over my north-east horizon: 


Amazingly, this was NOT my first contact from the DR with KX4WC/AM.  In January 2020 (just beore the pandemic) I was in Samana, and, early one morning Mike flew over the Dominican Republic.  Here is an e-mail that I sent yesterday to all three guys who were in this very memorable QSO: 

I really liked today's QSO.  Mike called me from around 50 miles out.  We were both very strong. 

The first link describes in detail my 2020 QSO with Mike from Samana, DR.   The second describes my Samana station.  

https://soldersmoke.blogspot.com/2020/01/aeronautical-mobile-contact-from.html
and

Here is my current station:


And wow!  WA3O  Who could forget that water-cooled amplifier!?  And I still have his HW-7   Thanks Mike. 

Tuesday, August 19, 2025

Coil-Making in Japan -- Manual and Automatic

 I found this video sort of soothing.  I liked the manual process, but the automatic process is amazing too. 

Thanks to Rogier PA1ZZ for sending this.  


Thursday, August 7, 2025

SolderSmoke Podcast 261: Travel, AI-Apocalypse, ARRL Award, Amplifiers (with Claude) , Transcoms, Smoke released in DR, QRP, CW, MAILBAG

SolderSmoke Podcast #261 is available for download: 



Alaska, Colorado, Dominican Republic

Opening:   Travel notes:    Pete to Denver.  Dean to Alaska.  Bill in the Dominican Republic. 

The future of the podcast.  We will embrace our NIMCEL status and fight on in spite of the AI Apocalypse.   Thanks to Peter VK3TPM, Hamilton KD0FNR, Sam AI7PR, Todd K7TFC  and the WayBackMachine for providing backup and transfer options for the blog. Google could end Blogspot at any time.    

Dean and Bill win the 2025 ARRL Technical Service Award.  Thanks to Bruce KC1FSZ for the nomination. And thanks to Bill Morine N2COP for letting us know.  91 receivers completed so far!  

SolderSmoke East was pleased to host Phil W1PJE, a distinguished MIT radio astronomer AND member of the SolderSmoke Direct Conversion Receiver Hall of Fame.   


Dean:   Amplifier design,  woes, triumphs, tribal knowledge.  And help from Claude. 

KK4DAS 100W MOSFET AMP

Pete:  Project X  -- The Transcom SBT-3Crossroads and Decisions

Transcom SBT-3

SHAMELESS COMMERCE DIVISION:   FIGHT THE AI-APOCALYPSE -- BECOME A PATREON SPONSOR.
GET BEZOS TO SEND US BEZOS BUCKS!  Use the Amazon link on the upper right.   
BUY PARTS AND STUFF FROM MOSTLY DIY RF. 


Bill: 
-- Smoke released in TWO RD06 finals.  Scrounged IRF-510s to the rescue.   
-- Working VK6 on 20 SSB.  
-- My old HW-101 -- inspired by Pete and by Will N5OLA.   
-- Eleven contacts on 40 with the DC RX and a Tuna Tin 2. Mike Bryce WB8VGE came back to my CQ! First ever QSO with SolderSmoke DC receivers on both sides:  K1OA-N2CQR.  
-- Do real hams use ALC? Do we really NEED ALC? 

Mailbag: 

Who is the Project 326 Guy?  A British engineer resident in China for last 20 years. 

Steve EI5DD  Ham Radio Ireland magazine.  Hey -- Why no Irish DC RX builders? 

Paul K9ARF -- Thanks for the very kind e-mail about SolderSmoke

Rogier PA1ZZ -- Many nice videos and suggestions on blog backup. 

Grayson KJ7UM on the EF-50 valve (thermatron!) 

Bruce KC1FSZ  Four DC RX builders at the Wellesley Mass radio club. 

Chris KD4PBJ -- Long trip to pick up two directional beacons possibly for 630m or 2200m bands! 

Alan W2AEW did a Minimum Discernible Signal test on the DC RX.  FB! 

Mike WN2A  -- Many great comments on MDS in its various forms. 

Philippe F6GUH is a FB homebrewer.  

Mike EIOCL -- Always great to talk on the air with an old friend. 

Walter KA4KXX -- I checked into the Sunrise net!  With my HW-101!  Thanks Walter. 

Farhan VU2ESE -- Watched our interview with Phil W1PJE

Phil W1PJE was an SWL with an old Halli receiver.  VOA?  Boo!  But Radio Marti is BACK! Also, the hydrogen line from the cosmic dark ages has red shifted to... 7.1 MEGA hertz!  So LISTEN UP! 
Phil W1PJE with a Halli and the Haystack Observatory Dome

Wednesday, August 6, 2025

Antenna Options and Views from the Terrace of SolderSmoke Shack South


Above is the view to the east.  North-east to Europe will be up to the left.  Straight out to the east gets me across the Atlantic to Central Africa.  


Here is the view looking south.   All of South America is down there, followed by Antarctica. Then up an around the pole to Sumatra and Borneo.  I can hear the Indonesians quite well on 15 SSB.   


Looking west.  Central America, then lots of Pacific Ocean all the way to Western Australia.  I have worked VK6JMS who is in the northern part of Western Australia, in "The Kimberly."



Here is the view to the north-west.  You can see how the top floor of our building blocks most of the signals from the U.S. and Canada when the antenna is at the terrace level (where it is now).    


I think I will stick with simple 1/4 wave verticals.  There is a lot of wind up here and we are not in the apartment about half the year.  I wouldn't want a Hex Beam to get blow over, especially when we are not here.  Simplicity is a virtue.   I think I can get the antenna above the top floor of our building by mounting it (base of the antenna near the top) on the support beam (for a sun shade) shown here.  This should greatly improve signals to and from North America. And I could easily take it down before we leave without having to climb up onto the roof. 

CuriousMarc Fixes the HP-182C Power Supply -- But More Fun to Come!


I really like how Marc stops and gives an account of all the parts he has changed,  and that he HONESTLY talks about parts that he mistakenly replaced, or replaced when the original turned out to be good.  Too often wizards write about their troubleshooting experiences and conveniently leave out these inconvenient changes.   But this is a big part of the troubleshooting game, and I am really grateful that Marc describes what really happens, WARTS AND ALL! 

I must say, Marc's replacement parts drawers are looking kind of empty.  He needs spare parts for videos like this.   

Wow, plastic polish!  Who knew?  I want some.   

Marc is a ham.  His callsign is AJ6JV. 

This kind of video is ALMOST enough to get me to work on my old HAMEG 'scope. 

In the next video Marc pledges to take on the 1966 trigger circuits.  

Tuesday, August 5, 2025

The Internet is Dying

 Thanks to Rogier PA1ZZ for sending this.  Rogier is a real human! 

Monday, August 4, 2025

ElectroBOOM! CuriousMarc Tries (and fails) to fix an old HP182C Oscilloscope -- Words of Wisdom for all Homebrewers


"You try your best to improve something that already almost works... and then you ZAP it entirely in the process.  This is the worst feeling ever.  But don't kick yourself.   This is our lot.  We are made to suffer." CuriousMarc

Indeed.  Take heart homebrewers.  Even CuriousMarc (who is a ham!) has been there and done that. 

This particular CuriousMarc episode was, I think, especially good: 

-- It reminded me of WHY I gave up on my beloved Tek 465 and went with Rigol DSO scopes.  I found I was fixing the Tek scope too often.  Plus, my Tek 465 had PLUG-IN TRANSISTORS.  Yikes!  One false move and you would insert 2 or 3 new problems into the already broken 'scope.  The high voltage in there was really scary.  I had to borrow a high voltage probe from Alan W2AEW.  I survived, but we shouldn't have to risk our lives for hobby test gear!

-- I would advise all homebrewers to be more careful around the really high voltages you will find in old 'scopes and TVs.  Remember the lesson of Ross Hull:

Read the article that starts on page 7:

-- Marc struggled with a junction FET.  This reminded me of the raging J310 debate on the Discord channel for the SolderSmoke Direct Conversion Receiver. 

-- We see the oscillator signal flat-topping when it turns on the diodes -- again DC RX memories. 

-- Marc had trouble seeing how the oscillator would start.  I too had trouble understanding how an oscillator would get going. 

-- At one point Marc replaced a transistor with a device that grounded the drain.  This will happen if you switch too quickly from say an RD06 to an IRF-510.   With the IRF-510 you need to insulate the tab from the grounded heat sink.    

It will be great to see, in subsequent episodes, how Marc makes it work.  It is really great to see someone present an unvarnished view of how troubleshooting really works.  

Thanks Marc.   73 

Here is Marc's YouTube channel:

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

FAKE, FRAUDULENT COMPONENTS on Ali Express


We had been thiking that no one would go to the trouble of deliberately labeling electronic components as something that they are not.  Surely, we thought, the fake components we were seeing we probably just factory rejects that were swept up off the floor and sold rather than being discarded. 

But it is much worse than that.  This video from Spain shows how someone is taking PNP transistors and DELIBERATELY labeling them as Unijunction transistors.  And then selling the fake UJTs on Ali Express. 

The Spanish video priducer is, I think, far to kind to the fraudsters.  He claims that they are simply trying to get a decent price for their product. Apparently, in this view, buyers are unwilling to pay what it would be worth to make REAL UJTs.  So, what is a producer to do?  Just take some BJTs and FRAUDULENTLY labelt them, selling them as real UJTs to unsuspecting buyers. 

There is no sugar-coating this.  This is fraud.  

The video from Spain appears above.  Here is the article from Hack-A-Day:

Sunday, August 3, 2025

Paul K9ARF -- SolderSmoke and a Knack Story


Bill:

Having been an occasional Solder-Smoke listener, I recently purchased your book "Solder Smoke Adventures" to read during vacation.  Previously I limited reading material to technical material, but I retired two years ago and can now allow myself to read stuff just for fun.  I devoured your book.

I found you and I to be kindred spirits, seeking to understand the mysteries of electricity and electromagnetic waves as we follow life's path.  We're close to the same age, you're a couple years my senior.

My fascination with electronics began as a boy when my Dad and I put together a crystal receiver as a Cub Scout project.  I fondly remember my father scrambling up on the roof to string a long wire as an antenna, and then listening to the Cubs ballgame in the earpiece.  No batteries required!

I exhibited "knack" tendencies later as an early teen.  At a local estate sale I picked up some magazines teaching basic TV repair, and a box of parts that previously was a portable B/W TV.  My family was amazed when I resurrected that little TV set.

My career path went into audiovisual interests - I heard broadcast engineers made a lot of money, so I went to Milwaukee Area Tech College electronics communications program.  The students there ran UHF channel 36 alongside the professionals running TV channel 10 (both pbs affiliates).  On the way to getting your 1st class "phone" license, we learned 2way radio (2nd class).  I found that repairing things was far more fun than pushing buttons in Master Control, so I ended up working in 2way.

While attending MATC, I met some guys who were hams - and they invited me to my first-ever hamfest.  Wow.  A gathering of electronics enthusiasts, many who also have "the knack".  I purchased a couple of old books cheap, not knowing this would steer my life in the future: the antenna book and a 1970s radio amateur handbook, both from ARRL.  Reading these books, I was intrigued by people who design and build their own equipment - the ultimate in coolness!

I guess what really kept me interested in reading your book is your desire to understand the basic building blocks of electronics - how does it work?  This mirrors my personal experience.  Though I have formal electronics training, my schooling was aimed mostly at troubleshooting, finding the malfunction.  The understanding of why the components in a circuit are the values specified and how they produce the desired output was, like you, a lifelong learning process I still work on today.

My adventure into Amateur Radio was delayed by life activities: marriage, a house, and a child.  It didn't help that I never met any hams in rural north Wisconsin.  I finally met an amateur who was a VE, and Radio Shack study materials had me on the way in 1990-91.

I tested in early '91 and passed the Novice, Tech, and 5 wpm code - the VE knew that I was a career radio tech, and at his urging I passed the General written test too.  My initial call was N9KQX (a horrible cw call).  The next months had me work on my code speed and study the Advanced material, and later I became KF9GQ.

At that test session, I sat alongside a gentleman who was taking his 20 wpm code test (wow).  A few months later he was one of my interviewers as I applied for a new job - Radio Tech for the Electric & Gas utility in Green Bay.  I believe my ham radio hobby helped me land that position, which I held 30 years to retirement.

When the vanity call sign program started, I changed my call to K9ARF "amateur radio fun" (yes, I like dogs...) or "analog radio fan" - life must include a sense of humor.

In my years as a ham, I have done quite a bit of homebrewing, from repeaters and accessories for my station, to test gear and complete transceivers.  My proudest projects were building W7ZOI's spectrum analyzer and a multiband KK7B based phasing transceiver using AA0ZZ's DDS synthesizer kits.

I want to thank you and the other solder smoke guys for what you do.  Hopefully I will someday have an opportunity to meet you in person to share a cold beverage, laugh and tell stories of molten solder variety.  Keep up the good work!!

73 de K9ARF Paul, Green Bay, Wisconsin

Saturday, August 2, 2025

Bill WA5DSS's FB SolderSmoke Direct Conversion Receiver

 

Bill WA5DSS built this beautiful receiver back in December 2024.  Somehow I failed to include him in our Hall of Fame.  Well, better late than never, right?   Please let me know if we have missed anyone else. 

I think it looks and sounds great, on both CW and SSB.   Note the Costa Rica station in there in the SSB portion of the recording.  

Back in December 2024, Bill wrote: 

Bill, Dean,
I forgot to send you a recording. This is what I recorded last night. I did not let it “warm up” so the stability is a little better after awhile. Also, I have a knob for tuning…just haven’t hacked off the head of the bolt yet.

I have put the receiver up for now. I am trying to get a Heathkit DX-60 on the air for New Years Eve Straight Key night. It’s the only time I attempt a straight key. Also I am amazed at how difficult it was to operate these old cw radios. No wonder I didn’t get many contacts back in the early sixties...

...This has been an interesting project for me. I have built many kits since becoming interested in electronics during the 1960s but this is the first time I have started with unetched boards. I think I prefer the “dead bug” style over Manhattan. I don’t have the patience to plan out where all those islands go! 


Bill WA5DSS

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