Hello Andy,
Well, fascinating history there, congrats on all that, but you are
showing your age a bit ;) What's this new WSJT mode "FT8" all about?
Too wide a bandwidth for LF, or of interest, anyone know much about it
yet?
Saturday, July 1, 2017, 5:34:05 PM, you wrote:
> Looking back in my logbook I see on the 12 July 1997 that I made a
> transmission on 73kHz that was received by G3PLX 393km away in a
> bandwidth of a few tens of milli-Hz. Peter was using the new fangled
> DSP stuff in a Motorola DSP card, to display the narrowband filtered signal
> on a waterfall display.
> I was radiating perhaps 5 - 10 milliwatts ERP (from a 200W transmitter)
> No information was exchanged that day, just confirmation of the
> carrier being switched on or off using the telephone as a back link.
> Peter suggested I write some software to generate very slow CW to
> key the transmitter and send it to him.
> On 27 July He received the first SLOWCW signal from me with
> positive ID of the callsign, sent according to my logbook notes with
> 100s dots between 0400 to 0718 UTC. We then did the same again
> for several nights running, varying the dot speed . This
> completely smashed the one-way distance record for the 73kHz band.
> There were several at the time who said "its not real amateur radio,
> it's computers talking" but those voices were soon silenced.
> Others wrote software to generate the keying and suddenly everyone
> started using SLOWCW which for some unfathomable reason started to be called
> QRSS (why ?)
> Now 20 years later, it still seems to be widely used, albeit with a
> few variations like DFCW to speed up exchanges.
> Andy G4JNT
--
Best regards,
Chris mailto:[email protected]
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