AA1TJ reports:
Breaking news from W1PID... "Mike! I just copied the beacon. I got 'VVV de AA1TJ 150 uw' and it faded out. 2146Z on 3551.95MHz" That's it! Jim copied a message produced by a lowly unijunction at a distance of 112km. How's that for cool! In a nutshell... the unijunction runs as an R-C relaxation oscillator at ~500kHz. A quartz crystal at the emitter frequency-locks the sawtooth waveform to 507kHz. The 7th harmonic is admitted to the antenna via a bandpass filter. The RF output to DC input conversion efficiency is all of 0.1%. Heat-sink? Check! Mission statement:
"...to boldly go where no unijunction has gone before." Cheers,
Mike, AA1TJ
I think the really cool thing is that EM waves are once again flying out of the Vermont Hobbit Hole, propelled into space by the poet laureate of QRP.
FreeDV Sunday net - 14 stations
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The weekly FreeDV net on 40m in South Eastern Australia was excellent this
morning despite wet weather here. Mark, VK5QI had planned a balloon launch
that ...
50 minutes ago
Hooray! Glad to see AA1TJ is oscillating
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