Dear LF Group,
Was interested to see Bill's report of the reception of LEK using
slow CW. I played the .WAV file back using spectrogram - I have to
admit I could not make out the CW by ear (it's rather a short
sample), but the signal is clear enough on the spectrogram trace -
it looks like 3s dots, once the compression factor of 40 is taken
into account.
Something else that is interesting is the noise on the display. If you
look at a night-time spectrogram at my QTH, it is like a crazy tartan
pattern, with vertical streaks every few seconds due to QRN, and
horizontal ones every few Hz due to various signals and Loran. On
VE2IQ's sample, there is nothing in the bandwidth apart from LEK
and what appears to be random noise (although I suppose this
would only correspond to a bandwidth of about 10Hz in real time) -
this is what it sounds like too. Is this an effect of the 'Crunch'
compression process, or does it mean that Bill's QTH is very quiet,
or mine is very noisy?
On 73kHz, The Rugby TX seems to have spent most of the last two
days transmitting a pair of carriers spaced 85Hz, centered on
73.250kHz - perhaps they have problems again. On Tuesday, they
shut down on schedule, between about 0800 and 1700. I Hope to
be QRV friday evening, and will also try to be on Saturday morning -
earlier in the year, the mornings seemed to be better for DX
reception on 73k. This week I will be listening for cross band
contacts too.
Cheers, Jim Moritz
73 de M0BMU
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