The recent debate on very tall masts versus slow digital signal processing
was quite amusing and yet slightly disturbing. The cost factors involved
on both sides were never mentioned and the assumption seems to be that
everyone has a digital computer, lots of spare cash and/or no local
planning restrictions. It is also notable that, in the recent suggestions
for partitioning the bottom end of the 73 kHz band, those using very slow
morse proposed grabbing all the best 50 Hz slots for themselves and
relegated manual morse to the worst spot at the bottom of the band, a
remarkable sense of priority which is not in keeping with equity or with
the better ability of digital integration to overide background noise and
QRM. It is very questionable if infra-slow morse should rank for dx
records for transmission but could possibly be credited in a special
category of reception. If the the slightest signal reaches the receiver it
is possible, given enough time, and a little ingenuity, to pull it through.
The very first radar moon echoes were detected in the presence of
background noise and interference by gating the received signals into echo
times centred around two and a half seconds and using very long integration
achieved by measuring the relative quantity of gas released from an
electrolite in a half hour period - that sounds like real ham radio but it
is true! (the experiment was performed by the Hungarian, Z. Bay, c1950).
Roger, G2AJV.
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