LF: DominoEX and FEC

["James Moritz" <james.moritz@btopenworld.com>]

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

2_dominos.jpg
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