Doug KB8M did a beautiful job with his Michigan Mighty Mite. But, as often happens, it still didn't work. He turned to us for advice. I gave him a long list of things to check, but Pete brought the power of superior tribal knowledge to the problem and spotted the defect immediately: The transistor was in backwards. It is a P2N2222. That means the pin out it C-B-E not the usual E-B-C. I had fallen into this trap with one of my BITX rigs and had to pull out and reverse many of those transistors. Fortunately for Doug he had used a socket for the transistor. TRGHS!!!!!!!!!!!!! JOO!!!!!!!!!!!
Podcasting since 2005! Listen to Latest SolderSmoke
Saturday, August 13, 2016
Wednesday, August 10, 2016
Some Really BIG Coils
I met W1VLF on 40 meters last week. "VLF" was a hint. And indeed, Paul has been experimenting in the 10 kHz range. His antenna loading coil is seen above.
More info here: http://rescueelectronics.com/9-Kilohertz.html
Very cool that Mike was working with Jay Rusgrove, W1VD, on this project. Jay designed the 6 watt VXO rig that was my first homebrew transmitter.
And additional VLF info here:
http://n3cxv.com/WH2XND_station_1.pdf
More info here: http://rescueelectronics.com/9-Kilohertz.html
Very cool that Mike was working with Jay Rusgrove, W1VD, on this project. Jay designed the 6 watt VXO rig that was my first homebrew transmitter.
And additional VLF info here:
http://n3cxv.com/WH2XND_station_1.pdf
Labels:
antennas
Monday, August 8, 2016
Saturday, August 6, 2016
SolderSmoke Podcast #189: Juliano Blue, FET Amp, Si5351 QSK, Bill LC VFO, QSOs
SolderSmoke Podcast #189 is available:
http://soldersmoke.com/soldersmoke189.mp3
Billy in Europe. Bill in Virtual Reality.
Great News: Little Gonzalo is "all clear." Thanks for the help.
BENCH REPORTS:
Pete paints the rigs blue.
Pete's FET amplifier project with FET switching and key pad
Using an Si5351 for CW offset and QSK.
Bill working on VFO for a rig built around HRO dial and gear box.
HRO gears seem a bit loose. What should I do?
The search for an Imperial Whitworth.
For variable caps, brass is better, but two bearings beats brass.
QSO REPORTS
Pete having fun with homebrew rigs.
Bill works K3MRK, WA3O, W4OP, W1VLF and N6ORS
MAILBAG:
Dallas CBLA
Conventional Current Flow Controversy
"I regret ever listening to your podcast!"
LCR recommendations
Gonzalo just turned TWO and is doing very well
Labels:
Juliano -- Pete,
SolderSmoke Podcast
Thursday, August 4, 2016
Dallas Mighty Mites from a MakerSpace
Bill,
I sent you an email a few weeks ago to let you know that I joined the
Colorburst Crystal Army and that I was preparing to teach a couple of
classes at the Dallas Makerspace on constructing the MMM. We had our
first class last night,
I sent you an email a few weeks ago to let you know that I joined the
Colorburst Crystal Army and that I was preparing to teach a couple of
classes at the Dallas Makerspace on constructing the MMM. We had our
first class last night,
https://talk.dallasmakerspace.org/t/build-a-radio-transmitter-class/11010/8
It was a great success, every student had a working transmitter at the
end of the class! So there are six new enrollees in the CCA! For all
but two of the students this was the first piece of radio electronics
they had ever built, including one who had been a HAM for 15 years.
Just wanted to thank you for preaching the MMM, it was just the simple
circuit needed to get folks started! We have another class on the 20th,
and requests have been made to schedule additional classes!
73
Walter Anderson
AF5WH
Labels:
Michigan Mighty Mite
Monday, August 1, 2016
Walking the Plank with N8NM's 60 Meter Rig
Steve N8NM writes:
The free-range rig is coming along! I'm receiving with decent sensitivity (my generator's only calibrated to -100 dB/m, and I hear a CW note there just fine) and I'm getting about -2 dB/m out of the mixer. Yippee!
I ended up using an IF of 20 MHz, mainly because I had a bunch of crystals left over from my Minima. The architecture (left to right) is: Diode ring mixer using 1N4148s, 20dB W7ZOI bilateral TIA, 6 pole crystal filter (BW ~= 2.3 KHz), Another 20dB bilateral TIA, 1N4148 product detector (cribbed from the Minima), 2N3904 audio driver, LM380 PA. Microphone amp is two FET stages (J310). Oscillators are courtesy of an Si5351, controlled by an Arduino Uno. T/R switching is done using a couple of counterfeit 2SC1969 RF transistors that, ironically, don't amplify at RF, but work fine as power supply "pass" transistors.
Yet to do is the PA, which I've noodled in LTSPICE (shooting for 20W PEP using a bunch of BD139s, just because...) and cleaning up my Arduino sketch. Right now, I just modified the start-up values of the sketch from my all-band rig for testing. Since that code is pretty full featured (dual VFOs, RIT, filter switching, LCD Display, etc.) using multi-function pushbuttons to select all sorts of crap, I'm betting that 80% won't be used in this rig. Adding simplicity is always good.
So, nearing the end, I'm already thinking about my next rig (that and building a 60m antenna...) I think this one will be similar to my "all band" rig, but limited to the WARC bands (I have a WARC tribander that's screaming for a rig of it's own.) That's kind of boring, so, to challenge myself, I'm going to try using a touch screen in lieu of the usual pushbuttons. What would really be cool, though, is an interactive slide-rule dial - don't think anyone's done that before! One of the things that has always drawn me to the SX-101 is that large slide-rule dial. To me, that allows each station to occupy a physical place on the dial, so after scanning the band, you know were everyone is. It's really a joy to operate those rigs!
73! Hope to work you HB2HB on 60M soon!
-Steve
Sunday, July 31, 2016
W9ZN's CW Warm-up: "Ben's Best Bent Feet"
I happened to come across this fellow's signal on 40 a week or so ago. His warm up routine really had me scratching my head. I've been on the air for a long time, much of it on CW, and I never heard anything like this. Listen to the video (!) and you will see what I mean. Harmless fun I guess, and there does seem to be a connection to radio history.
Labels:
CW,
Old radio,
radio history
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