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.
talkSPORT in the UK to close 7 AM transmitters on the Medium Wave band
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It was recently announced that OFCOM, the UK regulator has given permission
to *talkSPORT* to close down 7 of its 18 AM transmitters on the Medium Wave
b...
5 minutes ago
Hooray! Glad to see AA1TJ is oscillating
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