Look closely at the inscription on that USB stick. Obviously I sympathize. The folks at Boldport have some very interesting ideas and projects. And they operate from a very cool location, just south of the river Thames, not far from my old home in London.
Here is their main site: http://www.boldport.com/blog/2016/2/21/boldport-club-project-1
Here is where you can subscribe to receive a monthly project (with parts!) from them:
https://boldport.cratejoy.com/
As for the solder quote from Bob Pease, this was discussed before on this blog, back in 2011. We were talking about an intereview that had been done with Alan Wolke W2AEW:
I also liked Alan's response to the question about his favorite software tool: "Gee, solder is soft, can we consider that software? I use a lot of that!" This is very reminiscent of a quote from the legendary Bob Pease (colleague of Jim Williams): "My favorite programming language is solder." (That quote was sent to me by Steve WA0PWK. Thanks Steve.)
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Sunday, March 6, 2016
Saturday, March 5, 2016
AA1TJ -- On the Air with a Tuning Fork Transmitter using the 2,212th Harmonic and Olive Oil Cooling
The saturable magnetic frequency septupler. The tiny computer memory core is submerged in olive oil (Italian...naturalmente).
Not a very good picture, but here's the 1600Hz tuning-fork, fork oscillator, SRD pulse generator, PLL S/H phase-detector (diode gate), differential amplifier D.C. amplifier, and part of the 500kHz VCO.
The Wizard (AA1TJ) reports from the Hobbit Hole:
I was pleased to have made the first contact with my tuning-fork transmitter this evening. My contact, N1QLL, runs a pretty B&B on the Maine seacoast, midway between Bar Harbor and Cutler. Jerry was operating a solar-powered QRP station. I found a follow-up email from him when I came up to the house for dinner. He's asking for a better explanation of my set-up. I can't wait to tell him about the passive frequency septupler made from an East German computer memory core, heat-sinked in a thimble of olive oil.
My signal was also logged by a number of automated "Reverse Beacon Network" receivers (image attached) located in Ohio, North and South Carolina, Virginia and Pennsylvania...not bad for 90mW on 80m. Please note that my operating frequencies, 3,528.0 and 3,539.2kHz, are the 2,205 and 2,212th harmonics, respectively, of my 1,600Hz tuning-fork frequency reference.
FYI: the third attached image illustrates the block-diagram and tuning-fork reference oscillator circuitry for three common-wavelength AM broadcast transmitters operating in Berlin, Stettin and Magdeburg, Germany from 1928 through the mid 30's. A central 2,000Hz tuning-fork generated reference carrier was transmitted by landline to transmitters in the aforementioned cities whereupon the 529th harmonic was generated, amplified and broadcast at 1,058kHz. The equipment was designed by the Berlin-based firm, C. Lorenz A.G.. The fourth image details Lorenz' technique of frequency multiplication via saturable magnetic iron-core inductors. My septupler operates in an identical fashion.
A very pleasant day...
Mike points out that this is a work in progress. He hopes to cross the pond (the Atlantic!) soon. Here is a update from Mike:
A nasty cold has delayed work on the 20 meter implementation, although some of the time I've spent crashed on the sofa was put to use redesigning the loop filter network. I think yesterday might have been my "hump" day so I'm looking forward to getting in some quality bench-time over the weekend.
FYI: the third attached image illustrates the block-diagram and tuning-fork reference oscillator circuitry for three common-wavelength AM broadcast transmitters operating in Berlin, Stettin and Magdeburg, Germany from 1928 through the mid 30's. A central 2,000Hz tuning-fork generated reference carrier was transmitted by landline to transmitters in the aforementioned cities whereupon the 529th harmonic was generated, amplified and broadcast at 1,058kHz. The equipment was designed by the Berlin-based firm, C. Lorenz A.G.. The fourth image details Lorenz' technique of frequency multiplication via saturable magnetic iron-core inductors. My septupler operates in an identical fashion.
A very pleasant day...

A nasty cold has delayed work on the 20 meter implementation, although some of the time I've spent crashed on the sofa was put to use redesigning the loop filter network. I think yesterday might have been my "hump" day so I'm looking forward to getting in some quality bench-time over the weekend.
By the way, my PLL-based transmitter frequency stabilizing circuit has much in common with a garden-variety frequency-synthesizer. Obviously, the tuning-fork frequency reference is the main point of departure. My sampling phase detector, for example, was old hat by the mid-1960's. Nevertheless, this has been a fun project.
Labels:
AA1TJ,
Germany,
QRP,
radio history,
Rainey -- Michael
Friday, March 4, 2016
That Time We Were Re-Transmitted on 487 THz On a Red Light over Salt Lake City....
Some of you may remember this from back in 2012:
http://soldersmoke.blogspot.com/2012/09/soldersmoke-in-red-light-zone.html
Fast forward to November of last year. By this time I'd forgotten about the Utah light beams. Ron Jones, K7RJ, was kind enough to send me a wonder-filled bag of electronic parts. I have been slowly sorting them. All kinds of great stuff is in there, but I noticed a lot of stuff that you don't normally find in ham shacks -- lots of optical stuff, lots of LEDs and photo transistors, little transistors with lenses on the top. Cool stuff all, but not the kind of parts you'd use for a 40 meter CW rig. What the heck was Ron building? I wrote and asked. Here is his reply.
I’m like you, Bill, I’m a jack of all trades and master of none. I dabble in this and that. I always have a hand full of half finished projects on the bench.
The optical stuff probably fell on the floor when Clint (KA7OEI) and I were experimenting with “through the air light communication” a few years back. Clint in the real guru in that particular project. We made optical contacts over what we think is a world record – 173 miles! That meant packing in optical gear to the top of remote Utah mountains, but what a great time we had! We used a high power LED – NOT a laser. Lasers really suck for super long range communications. They are great for wide band across a parking lot, but not for voice communication over tens of miles (in our cast 173 miles) over the air. We did over 100 miles with a laser pointer – can you believe that? A $3.00 laser that you torture your dog with… 100 miles! But, that is a different topic. If you do say anything about the optical stuff, be sure to mention Clint, he really engineered the optical communication project.
By far, most important thing that we did with optical communication was on one of our short tests (only about 50 miles) when we broadcast one of the Solder Smoke episodes for anyone who cared to “look in” on our red beacon. I think Clint sent you a picture from his side of the path a few years ago.
If there are any parts in that pile of junk that you are particularly interested in, I may be able to find more data and/or circuit ideas I had. But, honestly, a lot of that is stuff that is as strange and wonderful to me as it is to you. Fun as heck to look at, but needs to be put in the “YAFP” pile (Yet another .. project).
Thanks for doing the podcast. It is always an inspiration for me to keep my soldering hot.
73
Ron K7RJ
Very cool. So Ron had been at the other end of Clint's Red Light beam, the light beam that was carrying a SolderSmoke podcast across Salt Lake City. And it appears that some of the parts involved in that amazing project have ended up in my junk box. The Radio Gods like this sort of thing and may have been at work here. Thanks Ron.
Labels:
Laser,
Light Beam Telephony
Thursday, March 3, 2016
DD4WH's Fantastic Teensy SDR Receiver (Videos)
This is almost enough to make me abandon my analog, discrete component, HDR fundamentalism. Check out that display. And that StereoAM mode in which the upper and lower sidebands go to the left and right headphones "useful for CW"... Wow, that's seems like a step beyond binaural.
Don't miss Parts 2-4 --They are all on YouTube and will appear in the right hand column when you are watching Frank's videos. But I couldn't resist embedding the video that shows the hardware. Note: the oscillator is an Si5351! Yea! And the LP filter board comes from Hans Summers.
Beautiful work Franz! Thanks for making the videos. 73 Bill
Labels:
Germany,
SDR,
Si5351,
Summers-Hans
Wednesday, March 2, 2016
From Paul Darlington M0XPD: A Book!
Our friend Paul Darlington M0XPD is a member in good standing of the International Brotherhood of Electronic Wizards. His AD9850 Arduino shield propelled me into the world of I and Q. His "Shack Nasties" blog is a valuable resource for all of us. And now he has written a book. Paul was kind enough to let me read it before it was published -- I enjoyed it very much. It is the story of a very personal journey. At one level it is about Paul's trip to the Dayton Hamvention. But the trip goes much further than Dayton, both geographically and personally. I especially enjoyed Paul's observations on the United States -- our British cousins often see things we ourselves overlook. I'm really pleased that George Dobbs wrote the foreword -- he is the ideal person to do this for Paul's very philosophical book.
We give "Getting There" our highest review: the coveted FIVE SOLDERING IRONS. And we are nominating Paul for a Brass Figlagee with Bronze Oak Leaf Palm.
Read Paul's description of the book here:
Buy the book here:
Congratulations Paul!
Labels:
books,
Dobbs-George,
hamfest,
UK
Tuesday, March 1, 2016
Radio Row, New York City, 1929
Labels:
New York City,
Old radio,
radio history
Monday, February 29, 2016
Antennas and National Monuments
We started SolderSmoke 185 with a brief description of my recent ascent to the top of the Washington Monument. A few days later I was visiting George K9GDT's wonderful web site
http://www.qsl.net/k9gdt/radio/radio.htm and in the humor section came across the above Gil cartoon from 1959. That is the general idea.
Pete then sent me this:
Pete originally had a three element Yagi coming out of Teddy Roosevelt's head, but that just wasn't right. I asked that it be changed to a 17 meter Moxon. Thanks Pete.
I would like to note for the record that I have no intention of using the Washington Monument, the Statue of Liberty, Mount Rushmore or any other national monuments as supports for any Yagis, Moxons, Cubical Quads, Ray Guns, Lazy H's, Inverted L's or any other type of electromagnetic wave launcher.
http://www.qsl.net/k9gdt/radio/radio.htm and in the humor section came across the above Gil cartoon from 1959. That is the general idea.
Pete then sent me this:
Pete originally had a three element Yagi coming out of Teddy Roosevelt's head, but that just wasn't right. I asked that it be changed to a 17 meter Moxon. Thanks Pete.
I would like to note for the record that I have no intention of using the Washington Monument, the Statue of Liberty, Mount Rushmore or any other national monuments as supports for any Yagis, Moxons, Cubical Quads, Ray Guns, Lazy H's, Inverted L's or any other type of electromagnetic wave launcher.
Sunday, February 28, 2016
75 and 40 Meter AM on my HQ-100 (Videos) + Digital Display
And here is how I sample the oscillator frequency for the digital counter. I use an old trick: I wrap some wire around the oscillator or mixer tube. I made the coil out of an old coil form. I had to play around with the number of turns to get suitable pickup on both 160 and 40 meters. The San Jian board allows for IF freq offset. I use a similar arrangement on the transmit side with the DX-100. By the way, the box that houses the two displays is the carcass of one of the Heath QF-1 Q multipliers from which I heartlessly pulled the nice reduction drive variable caps for use in my BITX rigs.
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Labels:
AM,
DX-100,
Hammarlund,
heathkits,
Old radio
Saturday, February 27, 2016
Sputnik Replica Transmitter, an "Error" in the Sputnik Schematic, and Why 20.005 MHz?

Mark K6HX pointed me to very interesting Hackaday article on Frank PA3CNO's Sputnik transmitter replica. As blog readers will recall, we went through a period of Sputnik-mania a few years ago: http://soldersmoke.blogspot.com/search?q=sputnik Chief Designer Comrade Mikhail Rainey AA1TJ sent me some of the Russian tubes (like those pictured above).
The Hackaday article pointed to our post reporting that Oleg RV3GM had found the schematic:
http://soldersmoke.blogspot.com/2013/04/sputnik-schematic-found.html Stefan reports that PA3CNO found "an error" in the original Soviet schematic:
http://www.radio.cc/post/Franks-power-supply-for-sputnik A mistake you say? HAH, I say! Hah! This must have been part of a sinister commie plot to prevent the capitalist imperialists from ever being able to reproduce the glorious transmitter of the Soviet people. They almost succeeded.
Just kidding.
In the course of looking through our old Sputnik posts, I came across a question I posted:
I have a question: OK so the crafty Soviets picked 20.005 MHz for some good reasons: Being so close to the WWV freq, it would be easy for hams and SWLs to find it with precision. In the November/December 2007 issue of "Break In" (from NZ -- thanks Jonathan-san!) ZL3DW notes that this frequency selection would allow a receiver set to exactly 20 MHz to "produce an audio tone plus or minus the Doppler shift without ever going through zero beat." But zero beat with what? Most of the receivers out there would not have had BFOs, right? So the Soviets wouldn't have been using ordinary CW, right? Were they using AM, with the beeps produced by an audio oscillator modulating the carrier?
Was their diabolical plan to use WWV as the BFO for those using ordinary AM SW receivers? If so, a 5 kHz separation from WWV seems to be too much right? Especially when the Doppler shift on approach would push the frequency up a bit. Maybe they just chose this freq to make it easy for listeners to find -- just a bit above WWV. Comrade Rainey surmised that they were keying the PA stage -- the oscillator "backwave" was at times audible on the ground.
What do you think Comrades?
DSW and 73.
Labels:
Netherlands,
New Zealand,
Rainey -- Michael,
Russia,
satellites,
space program,
Tubes
Friday, February 26, 2016
The Power and Potential of Small Computers (Quad Copter Videos)
Start by looking at this one:
https://www.ted.com/talks/raffaello_d_andrea_meet_the_dazzling_flying_machines_of_the_future
Then, for more details, look at these:
Labels:
computer history,
microcontrollers,
R/C plane,
Switzerland
Thursday, February 25, 2016
"Hot Iron" New Issue, Great Articles
Hot Iron is free. Tim writes:
"Hot Iron is published by Tim Walford G3PCJ of Walford Electronics Ltd. for members of the Construction Club. It is a quarterly newsletter, distributed by e mail, and is free to those who have asked for it. Just let me know you would like it by e mailing me at electronics@walfords.net"
Thanks Tim!
Labels:
UK,
Walford Electronics
Monday, February 22, 2016
SolderSmoke Podcast 185 -- SPECIAL FEBRUARY ANTENNA SHOW
SolderSmoke Podcast #185 is available
22 Feb 2016
http://soldersmoke.com/soldersmoke185.mp3
Travelogue: 550 feet above Washington DC
Bench reports
Pete: Simpleceiver update. Adventures in Raspberry Pi SDR.
Bill: A daring but failed attempt at divide by 2 I&Q.
Audio Mods on the Hammarlund HQ-100.
Dual Digital Readout for the AM station.
SPECIAL FEBRUARY ANTENNA DISCUSSION
Why we build antennas in February.
Why hams should concentrate on antennas.
The importance of noodling.
Pete's beam project.
Pete's Lazy H.
The pernicious influence of automatic antenna tuners.
Bill's Ray Gun Antenna.
Bill's Moxon and his 160 inverted L.
MAILBAG
Tom Gallagher NY2RF (new ARRL Exec VP).
Mike Rainey AA1TJ on the air with a unijunction transistor.
Dale W9DKB sends me 160 meter book.
Alan Wolke W2AEW builds a Mighty Mite.
Daniel HK4DEI builds a DSB rig in Medellin.
Chris KD4PBJ modulates an AD9850.
Charlie ZL2CTM Builds a Teensy Superhet.
Jim W8NSA -- a Tek 465 goes toes up.
Thomas KK6AHT has roof, needs antenna!
Grayson TA2ZGE homebrewing crystal filters in Ankara.
Ian G3ROO and I had QRP QSO in 2001!
Steven G7VFy sent me a box of VALVES.
Frank KM4AXA repairs a rig and thus adds SOUL to the machine.
Labels:
antennas,
Phasing Rigs,
SDR,
SolderSmoke Podcast
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