Thread: CW Skimmer
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Old February 18th 08, 07:41 PM posted to rec.radio.amateur.moderated
Michael Coslo Michael Coslo is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 828
Default CW Skimmer

Doug Smith W9WI wrote:
On Fri, 15 Feb 2008 09:39:13 -0500, Steve Bonine wrote:
My question, based on limited experience with the ability of computers
to copy CW in less-than-ideal conditions, is how many of the signals on
a crowded contest band it would actually be able to successfully decode.
Maybe this technology has made great leaps forward since I last tried
to use it, but I just can't see it being effective enough to dig the
signals out of the QRM and parse out the callsign.

I didn't find any actual use in a contest, so such real-world experience
would be most interesting.


W4LT tested it last night on 40 meters. After the contest is over I'll
see if I can find & excerpt his post. He seemed fairly impressed.

I wonder to what degree the improvement in Morse sending has made this
kind of project more effective? The quality of transmitted Morse (in
terms of spacing & element lengths being correct - and in terms of fewer
errors) has improved considerably since I got my license in 1973.



Certainly the ascendancy of keyers has helped, but even then, older
software had some issues with noise, signal level, and adjacent signals.

I'm a real dilletente on the subject, but I think that the older
versions of CW decoding software relied heavily on timing to try to
emulate the human brain's decoding of Morse. Trouble is, I don't think
our brains work that way, because humans can decode some Morse that is
sent pretty badly.

But the old software could have big problems when the sender didn't use
the proper space timing, or when the dashes or dots were significantly
long or short. The human just adapted in real time.

I think that is what the new software is starting to tackle.

- 73 de Mike N3LI -