I have been testing the difference between Op8 (8-second message) and
Op32 (32 second message). Thanks to the software, receiving stations
can report on both modes without having to switch.
Reports on my signals from PA0A, PA0AM, G4WGT and F6CNI (between 257
and 465km) show variable results. The slower speed never produced a
worse S/N, though sometimes it was exactly the same. Usually the
result was between 4 and 9dB improvement with the slower speed.
Intuitively, I would assume a 6dB improvement (though I am no digital
expert), but occasionally better iif QRM is present as I would expect
this to affect the faster signal more. Is this a reasonable
assumption?
Not a totally scientific test, but at least it demonstrates that it
is worth using Op32 when signals are weak.
I have now stopped Windows automatically rebooting my computer in the
middle of the night so I should be able to monitor all of tonight. A
nighttime transmit test is scheduled for the weekend.
Mike, G3XDV
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