Helge LA6NCA Builds a One Tube CW Transceiver -- And Makes a Contact!

Helge has done it again!  He has shown us the benefits of homebrew CW.  And he has done it with one tube.  FB Helge. 

Of course, I really liked the wooden box.  His is a lot nicer looking than mine.  I also liked how he carefully laid out the parts -- I seem to be stuck in my 13 year-old "build then design" mode.  Helge's way of doing it is better: design, build.   In that order! 

Some will quibble about a lack of 700 Hz offset between transmit and recieve.  With a VFO rig, this could lead to the stations chasing each other across the band.  But Helge is crystal controlled here, so I don't see a problem.  Is that right?  Please comment below. 

Thank you Helge for another great rig, a great schematic, and for showing us your obvious joy at reaching 400 km across the sea to your friend in Norway.  FB! 

The Roman Space Telescope

The New York Times reported today that you would need HALF A MILLION high definition TVs to display just one image from the Roman Space Telescope in full.  Wow. 

The telescope will be at L2. 

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

KW4H -- Steve -- "Knobs > Menus"

 

I really like the "KNOBS are greater than MENUS" sign.  For years we have been saying that menus are for restaurants.  FB Steve.  

Steve's resotation man-cave is very interesting, as are the rigs he has on the shelf or on the bench.  Lots of good work is obviously being done there.  

I also have one of those KP4USA QSL cards. Steve and I got into ham radio at around the same time, so it is possible that he was on the other end of that QSO.  I will check. 

Check out Steve's QRZ page: https://www.qrz.com/db/KW4H

W9TH - Jeff -- Shames Me Into Building a 6T9er -- "You Have No Excuse"

 

First off, that my friends is a ham radio shack.  Note the many books.  And the many Heathkit HW-8s and at least one HW-7. There is a 'scope.  And sig gens.  And a vise!  This is a thing of beauty.  

Jeff sent me a KiCad circuit board for an 6T9 transmitter.  He heard me moaning about it on the SolderSmoke podcast.   As he notes, I no longer have an excuse not to build this things.  The Radio Gods are demanding it.  Who am I to say no? 

Check out Jeff's QRZ page: https://www.qrz.com/db/W9TH

And his website: http://w9th.com/     (QRP before QRP was cool!) 

Thanks Jeff! 

"Solvitur ambulando." Latin for "It is solved by walking."

We've been proponents of this idea for a long time:  Essentially it is that sometimes you have to at least temporarily put a hard technical problem on hold.  Sometimes you need to just STOP working on the problem, put the rig on the shelf, and go out and take a walk.  Or, perhaps, a hike. 

In the travel section of the New York Times today, I found this phrase from Latin: "solvitur ambulando."  It was in an atricle by one of my favorite authors, Paul Theroux. One of his his novels, "The London Embassy" was eerily true to life, and had me thinking that the house he described was, in fact, the house in London that I was living in.  Paul has been at it for so long that, frankly, I thought he was gone.  I was delighted to learn that he is not, and that he is still writing books. 

Theroux wrote, "Is something fuddled in your mind? Searching for an idea? Then lace your boots, leave the house, and set off alone: Chances are you will find the answer along the way.  This remedy (attributed variously to Diogenes the Cynic and St. Augustine) is one that all true piligrims know, and in many respects serious hikers are the modern embodiment of medieval pilgrims."  

Indeed, if the solution is fuddled in your mind and you are searching for an idea, take a break, do something different.  Take a walk: "solvitur ambulando." 

Keeping the Voyager Spacecraft Alive

 

https://www.nytimes.com/2026/08/18/science/nasa-voyagers-big-bang.html?unlocked_article_code=1.8VA.nYO7.tliu0Kleh5vJ&smid=url-share

Here is a really nice New York Times story about NASA efforts to keep the Voyager spacecraft alive.  They are approaching 50 years old. They are very far away.  They are running low on the plutonium that keeps them warm and powered.  The fuel for the thrusters is starting to clog the pipes.  But NASA recently carried out a "Big Bang" effort to extend the life of these two spaccraft. 

One of the 25 year-old engineers admitted that he treats the Voyagers like he treats his aging parents -- problems do crop up.  But then he was reminded that his parents had been born AFTER the launch of the Voyagers.  

The animation above shows where the two spacecraft are, and where they have been. 

Solid State Transformers -- Are the small DC supplies from Amazon small versions of what we need?

The algorithm seems to KNOW what I have been reading.  This week the New York Times Sunday magazine had a really frightening story about the vulnerabilities of the U.S. electrical grid.  The big vulnerability is the large transformers.  They are very very hard to replace.  Replacement takes years.  If something were to happen to only a few of these transformers, the U.S. could be plunged into an apocalyptic power outage.  This is not theoretical stuff.  People in the U.S. have been taking out transformers with high powered rifles.  What is that old saying about people who live glass houses?   Well it appears we live in one. 

The NYT article ended with one optimistic note:  Solid State Transformers.  These are being used in the AI Data Centers.  Asianometry took a look at these devices -- I really like his YouTube channel, but I think he missed the big down-side of old clunky tranformers: their extreme vulnerability.  

One additional ham radio note:  Pete N6QW, Grayson KJ7UM and Helge LA6NCA have recently been using very small high voltage power supplies.  Back in the day,  thermatron rigs required much larger transformers.  Are these tiny DC supplies small versions of the Solid State Transformers discussed in the NYT article and the Asianometry video?   

First Earth-Moon-Earth Echoes: 1946 from New Jersey on 111.5 MHz using Military Radar Gear

https://www.nationalww2museum.org/war/articles/project-diana-moon-and-soviet-union

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

Maxwell's Equations Explained

I really liked this one, and the follow-on videos show a lot of promise.  The maker starts with the four equations that we see on T shirts.  He admits that at the time he first saw them, he did not understand.  But in this video, he digs in, and finally gets it.  The connection between Maxwell's equations and C (the speed of light) are especially well presented.  

There is a document that goes quite a bit further, and explores the connections between Maxwell's equations and quantum mechanics.  It is by that wonderful physicist Freeman Dyson. It is entitled "Why is Maxwell's  theory so hard to understand?" Check it out: 

https://davidtong.org/pdfs/teaching/electromagnetism/dyson.pdf

The Solar Eclipse in Spain, Balloons, and Veritasium

This was all pretty cool.  There was a lot of good scientific info.  I had noticed the crescent shapes on the ground during earlier solar eclipses (from tree leaves!), but I never knew WHY we were seeing them. Thanks for the explanation Veritasium.   

There was also a cool balloon launch and recovery, and some great video recovered from the balloon. 

It looked like everyone had a great eclipse in Spain. 

SolderSmoke Podcast 266: TROUBLESHOOTING! Test Gear, LA6NCA, ZIA Rig, Australia, Nuvistors, 75 AM, MAILBAG

SolderSmoke Podcast # 266 is available. 

Video version: https://www.youtube.com/watch?v=_hbLmsFxzx4

Audio version:  http://soldersmoke.com/soldersmoke266.mp3

Travelogue:   Dean to Boston, Bill to Glenmore in Maryland.  

Discussion of AI, data centers, and ham radio. 

Dean's Bench:  

--  Troubleshooting 

--  Why we emphasize building in stages

--  Understanding what your test equipment is telling you

--  Measuring everything and expecting precision from analog circuits.

  

--  Recent examples from our Discord channel, examples were my rigol scope was lying to me.

Pete's Bench:  

-- Helge LA6NCA's Rig

-- Troubleshooting when the data fools you:  The ZIA rig. 

SHAMELESS COMMERCE DIVISION: 

-- Mostly DIY RF. 

-- Please continue to comment on blog posts. 

-- Please think about becoming a Patreon sponsor/ 

Bill's Bench:  

-- Working Australia on 20 and 17 SSB. 

-- Putting 80 meter antenna back up.  But high (August) noise level on 75. SOLVED! 

-- Nuvistor adventures with 1964 Parks Electronics Converter. 6CW4s. 

-- Thinking of audio derived S-meters. 

Mailbag: 

Grayson KJ7UM -- admiration for Helge LA6NCA. 6L6 Rig. 

Hidehiko JA9MAT's super regen, And FT-101 VFO Box. 

Chuck WB9KZY on older UK covert listening devices. 

Paul VK3HN:  Australian CBLA rig. 

Andri in Bandung, Indonesia -- Built a SolderSmoke DC receiver. 137 built so far! 

Mike WN2A liked 3885 kHz post (not everyone did -- AI Slop?) 

Walter KA4KXX liked piece on G0UPL breaking the I and Q code of Si5351.

Bob KD4EBM and Peter VK3TPM on AI. 

Ryan KJ7KVD will build MMM when family duties permit. 

Chris KD4PBJ noted SolderSmoke on a ham radio sign sheet.  FB.

Eric 4Z1UG -- Interviewed Will N5OLA (Heathkit Guy) https://www.qsotoday.com/podcasts/n5ola

K6AUS seeking understanding on mixers.  FB! 

K6AUS:   Did Drake make any 2Bs with serial numbers 3000-4000? https://nomadiq.net/blog/post/how-many-drake-2bs-were-ever-made

I am still looking for a Drake 2B for K6AUS.

NT0Z -- Kirk.   A big fan. Thanks. 

Why is Lahti on the Dial of the Receiver? Where is Lahti?

I have seen Schenectady and even Springfeld (see below!) but Lahti was new to me. I spotted it yesterday on the dial of the receiver that the fellow from the UK was fixing. Lahti? What was that? 

Turns out, this is a European Longwave thing. 

Gemini explains: 

When you see Lahti printed on the dial of an older radio, it is typically marking a Longwave (LW) broadcast frequency rather than a shortwave frequency.

The presence of Lahti on the dial relates to several historical factors:

• The Lahti High-Power Station: Located in Lahti, Finland, the national broadcaster Yle operated a massive, high-power longwave transmission station on "Radio Hill" (Radiomäki) starting in the late 1920s. Because of its central location and immense power (reaching up to 200 kW in later years), its signal could blanket all of Finland and carry across northern Europe.

• Dial Navigation: On older European and world-band radio dials, manufacturers frequently printed the names of major high-power European broadcasting cities (such as Lahti, Rome, Berlin, Moscow, or Droitwich) directly onto the glass or metal scale. Because consumers tuned radios by city or wavelength rather than just abstract kilohertz numbers, these city names served as benchmark reference points for specific frequencies (such as Lahti's long-standing assignment on the longwave band, which eventually settled on 252 kHz).

• The Era of "All-Wave" and Multi-Band Radios: Older vintage receivers—particularly those manufactured in Europe or targeted at international markets—often featured multiple bands spanning Longwave, Medium Wave (AM), and Shortwave. Even if a radio is broadly referred to as a "shortwave" or multi-band radio, its dial layout almost always incorporated the Longwave band where powerhouse European utility and broadcasting stations like Lahti lived prior to the widespread decommissioning of European LW transmitters in the late 20th century.

The old dial on my wife's grandfather's receiver