Fine Jim,
Did you save a copy of the text ?
When you say the fec took longer to recover , was that at the expense of
missing text ?
I assume that the system is not quite as robust as olivia if you where not
seeing 100%
decodes? But at the data rate , that might be a miss observation ?
I had a couple of qso's with olivia on 7 mhz last night 8x250 it did
produce quite a good copy in qsb and recovered
very quickly .. may be a little wide for 7 mhz but with the shaped
modulation envelope,
very little spread. the data rate is 'just' qso speed
Thanks for standing by
Graham ..
--------------------------------------------------
From: "James Moritz" <[email protected]>
Sent: Sunday, January 11, 2009 12:23 AM
To: <[email protected]>
Subject: LF: DominoEX and FEC
Dear Graham, LF Group,
Quite interesting to watch the two modes (BTW, the continuous text gives a
much better comparison, thanks). At present, signal strength has improved
a
lot, and both signals are clearly audible between fades, which are 20dB or
more (see attachment). When near maximum, both modes print almost 100%;
the
FEC version corrects the occasional error due to static cracks and pops,
so
has fewer errors, but throughput is only half. When there are bigger
crashes, errors appear in the FEC copy as well, and it seems to take
longer
for FEC to "recover", so there are also more gaps in the copy, although
probably less actual printed errors. It also seems to take longer for the
FEC mode to recover after a deep fade. So the FEC does something, but in
this implementation, not really what you want... I suspect it would be
more
advantageous to go to the narrower-band Domino EX4 sub-mode rather than
use
the FEC.
Cheers, Jim Moritz
73 de M0BMU
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