Hi Bill I'm just getting back into ham radio after 33 years (last QSO: 1981), want to do it all through homebrew, seem to have the same mindset as guys like you and Frank K0IYE, bought your book [love it and Frank's], and just "discovered" the Soldersmoke podcasts. I've been
listening to them with one ear as I bike to and from work (about 40 minutes each way, so
it's almost perfect). I'm employed as a digital geek, but yearn for the
days of DeMaw's prime (worked him once when he was W1CER), when the 40673
ruled. I'm very glad that, 40 years later, people like Farhan can weave
discrete analog wonders, even if they later choose to use digital *control*
(NOT DSP! No!). I had to start somewhere with your podcasts archive, so I started with 2014 and really enjoyed your struggles with the Herring-Aid 5. My 1st receiver was the "DC 80-10" by DeMaw from somewhere around 1970
in QST or the Handbook -- used a CA3028 as the product detector -- and I had similar
struggles. While listening to it, I immediately thought "you wound the feedback coil backwards, you idiot!" I got my license back in March 2014 and want very badly to get back on the air with a homebrewed, or at least minimally-kitted, station. I've built the receiver: David White's (WN5Y) Beginner's and Experimenters receiver heavily modified, have a long wire antenna up, a decent RF ground, and all the parts I need for QRP z-match tuner, swr meter, T/R switch, sidetone, and IRF510-based transmitter. Target: 40m CW by
the middle of December, 30m in the couple of months after that with a fully-Manhattan-style Barebones Superhet and another IRF510 transmitter. Then one of these BitX things. It's been a couple of decades since I felt that there weren't enough hours in the day. Some nights I can't sleep, what with all these transistors and simple analog ICs whirling around... Anyway, keep it up, I'll be listening. -- Paul Lender, AD0HQ  I built an Arduino/AD9850 DDS -- a la AD7C -- and used it to tune a 4-crystal filter (10-cent crystals from Tayda!) for the receiver with the same Rigol scope that you use. I tried, really tried, to do it with an analog RF signal generator. Change is good. Change is good.
This is what all the cool homebrewers will be wearing next year. Just be careful at airport security -- they might not understand! Check it out: http://www.johngineer.com/blog/?p=1595 We received some comments from some noted Thermatron authorities:
This will cause all of the bells, whistles and sirens to go off all it once.
Now all that is needed is a logo on the watch that says
EBOLA ( Electronic Bi-state Operational Long Arithmetic) and this will cause you to go to jail without passing Go or collecting $200.
--------------------- Wow, I love this thing!…even though it uses little black plastic things to work. Have no idea what they are. (johngineer has knack squared)
Reminds me of a project I am trying with fellow ham. We picked up an old HP nixie tube freq counter at junk yard. We were going to strip out the nixie tubes to make a clock, but decided we could make it as clock as is. Want to program an Arduino thing into generating a frequency that is the time and feeding it into the counter.
For example 3:45:25 would be 34,525 Hz.
But my Italian is terrible so haven’t been able to get the Arduino to work. Just learning it. Project a bit over my head. picked up one of those online language courses on Italian. Hard, but not as hard as Turkish!
The SolderSmoke legal team (we too use Dewey, Cheetham & Howe!) has advised us to be very careful about divulging the details on this rig. They are not sure about the statute of limitations. Beyond what he said on the podcast, all Pete will say is that TOOBs were involved: 1S4, 3S4, 3Q4, 3Q5, 3V4s. He says power out was ALWAYS less than 100 mw ERP. That's his story and he's stinking to it.
Thomas, KK6AHT, was in Washington this week. He and I got together for a beer and a look at his Minima.
I'd seen pictures of it, but it was much more impressive in person. Thomas did a great job on this rig. It is a really nice mixture of digital and analog. I liked the fact that he built the analog portion Manhattan style using MePads. He and I agreed that while it would make sense to produce a PC board for the Arduino/Si570/LCD portion of the rig, builders should be encouraged to do the rest Manhattan style.
Showing true homebrew dedication, Thomas was unhappy with the level of audio output when we turned it on. He started to trouble-shoot right there in the Ruby Tuesday bar!
It turns out that we were in a very Knack-ish location. We were on the site where they created ARPANET. Thomas very kindly left me with a nice package of Minima digi-parts including the Arduino chip loaded with the software and an SI570. So now I have no excuse. Thanks Thomas!
I am a long time listener of SolderSmoke and a big fan! Since your last podcast was on the use of Arduino’s for ham radio, my Arduino Hellschrieber project may be of interest to you and your listeners. I am using the $15 dollar RadioShack color display they are closing out and a simple circuit with our favorite transistor!
I have a video in my second blogpost and all the details with code below.
I have learned that esteemed homebrewer Michael Rainey, AA1TJ, recently whipped up a 56 MHz, quarter-wave, helical coaxial resonator (BTW: the spoon is also homebrew). Hmm, 56 Mhz. Or perhaps we should say MegaCYCLES? Michael claims this device is for a low phase- noise VFO, but I find the frequency selection highly suspicious. The last time I heard of that frequency it had to do with an underground group set up by the late (or not so late) Frank Jones. Here is all the info on Frank's Five Meter Liberation Army. http://www.sunflower.com/~brainbol/frank/ A man of the '30s awakens one night in the '90s (episode 13) with a new mission: recapture 56-60 mc. He forms a Five Meter Liberation Army from his mobile home in a Barrio trailer park run by Tom Joad of Steinback's Grapes of Wrath (episode 9), and soon draws a decidedly uncolorful bodyguard (episode 7). A six foot tall half Mexican stockbroker named for Ayn Rand makes him rich and a demonic white ferret and a half-siamese cat become his familiars. (episodes 10 and 9). The leader of all this, called only "Frank," settles down in the narrator's basement to be joined by Maj. Armstrong (episode 8), Hiram Maxim (episode 23) and one-time pals Carl and Jerry from the 1950s Popular Electronics (episode 25). His huge 1940s sedan, with contemporary plates, is immune from police (episode 13 et seq) and his breadboarded electronic creations recall those distant days when a ham built his own rig and could "fix a radio." Of course all this is crazy. No one builds anything anymore and the other things Frank stands for, like self- reliance, tolerance and a generally Boy Scout viewpoint are simply out of step. Frank knows that too (episode 20), but he does not care. If you're standing in the middle of the road and see a big brown Frazer coming at you, you better jump - one way or the other. VIVA EL FMLA! VIVA!
This is the guy who wrote the biographies of Einstein, Steve Jobs, and Ben Franklin that I've been talking about on the podcast. President of the Aspen Institutes, former Chairman of CNN and editor of Time Magazine. And, as I learned today, a former ham radio operator. In his new book, "The Innovators," he writes: "My father and uncles were electrical engineers, and like many of the characters in this book, I grew up with a basement workshop that had circuit boards to be soldered, radios to be opened, tubes to be tested, and boxes of transistors and resistors to be sorted and deployed. As an electronics geek who loved Heathkits and ham radios (WA5JTP) I can remember when vacuum tubes gave way to transistors." When I told Billy about this, he said, "No wonder you like his books so much!" Indeed. Walter has THE KNACK. I'm enjoying his book, "The Innovators."
Sometimes it is good to take a break from the electronics and look at how people are making other things. I've been working on the heat sink for a 140 watt solid state amplifier, so this fellow's comments about working with metal kind of resonated with me.
I heard your description of the echo on your podcast and
before listening I knew the cause - but I think you know that now!
Yes, it's from two separate transmitters, and quite common,
though not usually noticed.
It has nothing to do with path length differences - the
longest round-the-world echo via the ionosphere is only about 0.15 seconds - so
anything more has a different cause.
It's from the audio feed to the transmitter. Your regen
receiver picked up two transmitters on different frequencies. It was very
noticeable before transmitters used digital land-line feeds, just analogue and
On a BBC SW frequency (forget the which one now) one tx was
in UK and the other in Singapore, on the same frequency with the same programme
to completely different service areas. When propagation was right and listening
in Europe, the UK signal fed by analogue audio from Bush House came first and
the Singapore tx came with two geostationary satellite delays later, plus the
tiny bit of UK-Singapore ionospheric path difference.
Now it's worse because there are all sorts of digital delays
via land-line and satellite, although using the same frequency for the same
service in not common.
In the UK Absolute Radio on AM medium-wave has multiple
transmitters (mostly 1215 kHz and 1197 kHz) on the same frequency which are
audible at night. If you listen carefully you can often hear multiple (up to
FOUR!) echoes from different transmitters all being fed by different internet
feeds/satellite links with varying delays.
As an ex-BBC engineer, I can tell you that in the old days
not only were these AM medium-wave group stations all synched to within 0.05Hz,
but the phase of the modulation was adjusted so all tramsitters were modulating
in phase! Now the commercial boys have taken over most of these syched groups,
not only are the frequencies all over the place, but the modulation isn't even
time delayed to match, let alone synchronized! Some even put diferent
commercials in the breaks so if you're geographically between stations you get
a complete, unlistenable-to mess. Apparently these days that's ok.
Why did we bother...?
Anyway, I hope this adds to and confirms your findings.
Wow, the Minima presentation by Thomas at Pacificon was really great. I think he had exactly the right tone and tech level for the digitally-savvy California audience. His very open description of the ups and downs of his Minima build will surely lure in some new builders, and will at the same time prepare them for the travails ahead! Great stuff. I like the mention of Pete's "noodling." Thomas obviously gets it. And he obviously has THE KNACK. Thanks Thomas! Thomas has posted his slides and (MOST IMPORTANT) the audio of his presentation. Just click on the BIG ORANGE play arrow below the slides. You folks will love this: http://www.sarfata.org/2014/10/Minima-Presentation-at-Pacificon/
After using the Arduino DDS as a crystal substitute with my 1982 Barebones Superhet recevier (scroll down), I moved back two more decades and used the DDS as a crystal substitute to put my (early '60s) Drake 2B on the 12 meter band. This was a hack in which I actually used a hack saw -- I used it to cut open the container holding a crystal so that I could make a socket that would carry the signal from the Arduino DDS into the Drake 2B. This video is a bit repetitive, but it stated out at two different videos. I just put them together. The last part shows the actual crystal socket hack.
I like it! You and I may be the only people in the world with that kind of VXO range control switch on the front panel!
I checked my VXO. I run it at around 23 MHz. I use two single crystals, also switched by a relay.
The 23.144 rock tunes from 23.127 to 23.151 24 kHz
The 23.166 rock goes from 23.144 to 23.168 24 kHz
So I could have had 48 kHz were it not for the overlap. As it is, I get 41 kHz. Not bad.
The reason I went with this LO freq was that I had these crystals from the Dale Parfitt/Doug DeMaw Barebones Barbados Receiver. DeMaw had used color burst rocks for a 3.579 MHz IF, but Dale shifted up to 5 MHz. I could occasionally hear WWV! (But with the 3.579 I heard W1AW in the IF!)
Wow. This guy has a really inspirational Knack story. He welded (with coat hangers!) a sidecar onto his bike when he was a kid. He majored in Physics and Theater. He did all kinds of hardware and software hacks. He plays a Theravin in a band. He now flies spacecraft for the Jet Propulsion Laboratory. And Congratulations to Peter Parker, VK3YE, for having one of his ingenious hacks picked up by Hackaday: http://hackaday.com/2014/10/06/dusty-junk-bin-downconverter-receives-fm-on-an-am-radio/ Thanks Hackaday! And Happy Tenth Birthday to You!
I talked to him last night on 17 meters. He's a nice fellow. When your first name is Edison, that's an indication that you might have THE KNACK. From his QRZ page: Ready for this? My wife and I have lived off-the-grid for more than 24 years. Solar and wind are our main power sources on our mountain, although, we did finally add a generator to our available power sources, for those long days of "NO SUN" in Winter. Check out the view from my home at this site: http://mycampage.com/rosevalleycam and also look at the other links on the page. You might find something you like.... I've been a ham since 1967. Started as a Novice near Sacramento, California, where I was born. But WN6FIC soon became WA6FIC, which I remained until the late 90's, when I became N7GCW. I am a musician. Along with my wife, and Blaine Lindgren, our fiddle player, we comprise the band called "Half-way There". Click on my campage link to see more about me, and you will find all of my other links there too. I am also a photographer. I shoot it all, but REALLY enjoy taking pictures of scenery, and live bands at Concerts we go to. I am also very fond of Sunrises, and Sunsets, and they ARE beautiful here..... Also, check out his TREK page: http://n7gcwtrek.weebly.com/index.html And I liked his description of his county in Washington state: "...I absolutely LOVE my world, here in our little valley. Our friends are like
family here. People smile and wave...and mean it! We heat exclusively with
wood we cut from dead trees on our land, use propane for cooking and
refrigeration, and we use solar and wind for most of our power needs, only supplemented by a generator in those long days of no-sun in Winter. It's like
living in a time warp, here in our neck-of-the-woods.... Do you know that there
isn't a traffic signal in the entire county?" See: http://edisonshomesite.weebly.com/
Another great video from the famed Italian Director Giovanni Manzoni! Bravo Giovanni! Pete's discussion of double balanced mixers and the associated toroids has made me feel uneasy about my efforts in this area. I wonder if my diodes were completely matched. And I KNOW that my toroids are not as well done as Pete's. I recently put an SBL-1 into my old, long-evolving 20 meter ceramic resonator DSB rig. Careful with those nice little boxes! A bit too much juice and you can fry the little internal toroids (as I have done!). A while back I found in an RSGB Handbook a nice diagram showing how the diode ring mixer does its thing:
SolderSmoke Podcast 166 is available for download: http://soldersmoke.com/soldersmoke166.mp3 Bench Report: Pete working on Direct Conversion Receivers. Bill on his 2B and on 20DSB rig, and an M0XPD/Kanga DDS kit, and a 140 watt amp. GETTING STARTED IN HOMEBREW: Start simple: Build an oscillator. Make it oscillate! Gather tools, simple test gear, and books. Try to understand what you build. Build a direct conversion receiver. Don't fear the toroids! Be patient. This is not Plug and Play. Build a DSB transceiver. Little tips: Protect variable caps. Use heat sinks. Use reverse polarity protection. Don't breathe the solder smoke! Ventilate your bench. China Radio International Mystery Solved. Book Recommendation: "International QRP Collection" by Dobbs and Telenius-Lowe MAILBAG
Bil Herd of Hackaday did a very nice video on Sine Waves, Square Waves and FFTs. This is, of course, an important part of understanding how mixers mix. I look forward to his upcoming video on Direct Digital Synthesis.
In response to popular demand, "SolderSmoke -- Global Adventures in Wireless Electronics" is now available as an e-book for Amazon's Kindle.
Here's the site:
For the print version:
For shipping from a printer in the U.S. (probably better for N. American buyers) Click here: SolderSmoke USA Version
For shipping from a printer in the UK, Spain, or the USA (probably better for UK and other European buyers)
Click here: SolderSmoke EU Version
The two versions are identical, except for a minor difference in the paper used. That's why the prices are a bit different.
Bill's OTHER Book (Warning: Not About Radio)
Click on the image to learn more
W4HBK's QRSS Grabber: The Amazing Pensacola Snapper (Live!)