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Thursday, November 30, 2023

AA9IL's Sputnik Tube, Altoids Tin Transmitter

November 24, 2023
Hello Bill
I have just built an tested a 20 meter “Sputnik” transmitter. It uses two Soviet era “rod” tubes and is fixed tuned to 14.060 MHz.  I was able to compress the design to fit in an Altoids tin. The plate tuning capacitor was replaced with a fixed capacitor value closest to the variable for peak power out. Plate voltage is 90 volts and I key both the oscillator and PA via the B+ line. Power output is around 200mW and my first test transmission from the Chicago area was picked up 864 miles away on the east coast via the Reverse Beacon Network. It was definitely Joy of Oscillation and Joy of Transmission!

73, Mike

Mike's rig has been heard by many Reverse Beacon Network stations: 

November 29, 2023
I started a QSO with AC2C in Ellicott, MD who responded to my CQ but the band dropped (20m)
But that’s a good start and I’ll keep at it!  So, yay!
73 Mike

Here are some earlier blog post on rigs using Soviet rod tubes: 

Wednesday, November 29, 2023

Other Workshops: Genius Girl Fixes (Re-builds!) Old Tractor

This is amazing.  I put it in the "other workshops" category, but when you watch this you will see that she re-builds this tractor with NO WORKSHOP AT ALL.  It seems to be done at roadside and on the front yard of her house.  With some very basic tools. 

I would be a complete mess if I tried this.  And I would fail to get it going. 

I have posted about Lin's projects before.  See:  https://soldersmoke.blogspot.com/2022/04/the-next-time-you-hear-someone.html

Monday, November 27, 2023

Video on Discovery and Restoration of the Apollo Guidance Computer

I've probably posted before about CuriousMarc's efforts to restore the DSKY Apollo Guidance Computer.  But this Wall Street Journal video sums it up and adds detail about where the computer they worked on came from:  the guy in the video found it discarded in a junk warehouse that he bought in the 1970s!  Those of us who scour those under-the-table parts boxes at hamfests will appreciate this find, and the ensuing restoration. 

Saturday, November 25, 2023

Some Short-Wave Listener QSL Cards

Click for a better view

I haven't received many, but I always like QSL cards from shortwave listeners.  Someone out there is listening!  

The top one is from recent contact. It arrived from Hungary via the W2 QSL bureau.  Here is Tamas HA00001: 

The middle one is from my youth.  in 1975 Nick in Moscow USSR heard my contact with OD5IO.   I didn't remember the contact with Lebanon.  It turns out that the operator was K4NYY (who is now a silent key.  See https://www.qrz.com/db/K4NYY/?mlab=). 

The bottom one pre-dates me by more than twenty years.   It comes from Berlin in 1936. W5AIR was heard working EI7F on 20 meter CW.   Does anyone have any info on this SWL? 

Over on The SWLing Post blog,  readers posted this info: 

Friday, November 24, 2023

A FREE Book from the Early Days of Ham Projects with Transistors: The CK722 -- The Device that Got Pete Juliano Started in Homebrew

Pete N6QW sent this amazing book to me this morning.  Pete wrote: 

"The book was the size of a Notebook and had a gray cover. I built some of the projects like the CPO. If you had a CK722 then you were there."

You can get the book for free here: 


The impact of the CK722 on Pete Juliano, on ham radio, and eventually on SolderSmoke was quite profound. Back in 2015,  I wrote about this on the blog

I knew Pete had a lot of experience with transistors, but I didn't realize just how far back this experience reaches.  Pete writes, "The March 2015 issue of QST  had an article about a 1953 transistor transmitter project which was really advanced technology since the transistor was only invented about 5 years before that time...  About 1953 at the age of 11, I built my first solid state audio amplifier using the venerable CK722 from Raytheon. The transistor did look a bit strange in that cool blue cube shape with a red dot on the side to identify the collector. What a joy and surprise to me that it worked the first time power was applied...  It  was the CK722 that in large measure started me on a life’s work and engagement in a wonderful hobby. That CK722 path also led me to designing and building a QRP solid state version of the Collins KWM2 which I call the KWM-4."  I asked Pete why an 11 year-old kid in 1953 felt compelled to build a solid state audio amp.   The answer is very cool:  Pete's father had introduced him to crystal radios at age 8.  Pete wanted an amplifier for his crystal set, but his dad was worried about him building high voltage tube gear.  So that's how Pete got his VERY early start with transistors.

We are really lucky to have Pete Juliano sharing his vast tribal knowledge with us.


You can see a complete set of SolderSmoke posts about the CK722 here: 

Wikipedia has a nice article on the CK722.  The design contest Raytheon sponsored would be the kind of contest we could really get into!  https://en.wikipedia.org/wiki/CK722

Thanks Pete.  And thank you Raytheon! 

Thursday, November 23, 2023

Other Workshops: A Twin Cylinder Solenoid Electric Motor and some Very Cool Craftsmanship

This project caught my eye for a couple of reasons:  

First, it is the product of a very cool metal shop and a very skilled craftsman.  It is fun and inspiring just to watch Maceij build this motor.  We see great precision in the metal cuts, speedy tap and die work, and some great PC board technique.  The use of an open flame on the heat shrink material was, well a bit courageous. 

Second, this is a far more sophisticated version of the trivial electric motor that my son Billy and I built 17 years ago (I still have it!), following up on inspiration from Alan Yates VK2ZAY (see below).   With Alan's device we turned on power to the commutator by just sanding away the insulation on one side of the enameled wiring.  Maceij takes a much more sophisticated approach, with carefully milled switches and opto controllers turning on and off power at the right time to each of the solenoids.    


Maceij's YouTube channel has many other projects, many like this one:  https://www.youtube.com/@maciejnowakprojects 

Thanks to HackaDay for the heads up. 

Tuesday, November 21, 2023

On my Second Day on 10 meter AM, I Worked K5JC -- the Creator of the Mod that I was Using (Video)

See video above.  This happened on my second day on 10 meter AM. I was using the little GE CB radio that I had modified for 10 meters. I had lucked out. First bit of luck: the CB that I bought (for parts!) at a hamfest turned out to be just the thing I needed for a quick and easy mod. The GE box had what is called a Hygain board and -- most important -- a PLL02 chip. Second bit of luck: I stumbled across an article by Jerry K5JC on how to put this particular kind of device onto 10 meter AM. Boom, Bob was my uncle, and I got on 10. Then, today, the miracle happened. I heard Benny K5KV and I gave him a call. He asked about my rig. I described the mod to the GE CB. Benny seemed kind of surprised, and for good reason. You see, Jerry K5JC (the guy who created the mod that I was using) had just broken squelch on Benny's rig! Benny told him to get on 10 and soon I as in contact with the guy who had created the mod that I was using. The Radio Gods Have Spoken. Thanks Benny and thanks a Jerry. This was all really cool.

Think of odds of this happening: On my second day on 10 AM, running just 4 watts, I just happened to contact Benny K5KV in Texas who just happened to be in 2 meter range of Jerry K5JC, who just happened at that moment to be breaking squelch on Benny's 2 meter rig. TRGHS.

Bill's Fortune Cookie

 TRGHS (The Radio Gods Have Spoken)

Mr. Carlson's ART-13 Transmitter (with Dynamotor)

Here we have a really cool video from Mr. Carlson.  In it he reveals (admits!) to what we already know:  HE IS A HAM RADIO OPERATOR.  FB Mr. C!

You can see that he is a true ham, with a true case of THE KNACK, when you see his reaction to the inside view of the ART-13.  He seems to gasp as he notes that there is a lot of "RF goodness" in that box.   There is a vacuum relay, a bread-slicer capacitor, there is even a variometer. And lots of good, big THERMATRONS.  Only a true ham, a true Knack victim can recognize this RF goodness. 

The Dynamotor that goes with this transmitter is really interesting to me.  I have been hearing these things whining in the background (audible noise, not a signal defect) on many early morning (Saturday 3885 kHz) of the Old Military Radio Net.  I can often hear the dynamotor of Buzz W3EMD as he transmits from Rhinebeck, New York.   It was great to see the inside of this device.  

Back in 2017, Hack-A-Day took a look at Dynamotors: 

There are several good ART-13/BC-348 pictures on W3EMD's QRZ page:

I was especially taken by the handwritten frequency chart on the front panel of the ART-13.  This reminded me a lot of the handwritten readout that I have been using on various rigs, including (most recently) the 15-10 SSB transceiver. I hope Paul focuses on this paper-and-pencil frequency chart;  it is nice to step away a bit from the glowing numerals of San Jian. 

Mr. C points out that the ART-13 was the transmitter that was paired up with the BC-348 receiver.  He will be working on both in the weeks ahead. 

Thanks Mr. Carlson. 73 OM. 

Thursday, November 16, 2023

Bill N2CQR Goes Citizen Band

 10-4 Good Buddies! 

The Grid Leak Detector -- Follow-up from Yesterday's Post on the Whole Earth Catalog's "Hippy" One Tube Receiver

Click on image for a better view
When I first looked at it in the Whole Earth catalog circuit, I thought it was a regen.  But a commenter correctly questioned this conclusion.  I remembered the grid leak circuit (WN2A provided more info in the comments).  This morning I found a Wikipedia page that explains it all very well.  I especially like the description of how this detector works both with small signals in the "square law" range of the tube, and with larger signals in the linear range of the tube.  The history of the discovery of the need for the large resistor is also very interesting.  I remember building FET amplifiers and finding that they would -- after time -- shut down.  This would happen as charge built up on the gate.  I had neglected to include the normal 100k ohm resistor (that would "leak" this charge to ground).  Once I put this resistor in, the amp worked fine.  

Here is the Wikipedia article:  

Wednesday, November 15, 2023

Whole Earth Catalog Part II: More on SWL (and a Hippy One-Tube Receiver)

Click on image for a better view

Lee McKusick was correct about many things, but of course we were a bit disappointed by his focus on store bought gear.  But the 1971 Whole Earth catalog made up for this by publishing the schematic for a very simple single-triode receiver: 

Click on image for a better view

There is a follow-up article on grid leak detectors here: 

Designer: Douglas Bowman | Dimodifikasi oleh Abdul Munir Original Posting Rounders 3 Column