Re: LF: M0BMU test transmission on sunday evening.

[DL4YHF@aol.com]

Hello Jim, Markus and group.

> didn't know there was such a thing as a "squelch killing postamble tone",
> so my hardware may be ignoring it - what form does it take?


Your TX hardware does not ignore it, Jim...
my receiver ignored it in the QRM, and it was not visible on the spectrum here. But it can be seen in a screenshot of your transmission which Markus sent me (see attached image).

It is just an unmodulated carrier at the center frequency, visible on the right side.
If the PSK31/PSK08 decoder detects it, the accumulated 'squelch' value is cleared.
In PSK08 mode, the postamble tone is transmitted for about 4 seconds. The "LED" is yellow during this time (steady, flashing yellow/red indicates "TX buffer empty").

>
> So congratulations are due to DL4YHF...

Thanks for the flowers, I'll have to pass them on G3PLX who had the idea for PSK31 and did the hard work to implement it for the first time.


As I see it, PSK08 is a 'quite weak signal mode' useful for communications with a fair amount of information exchange but cannot be compared to 'real weak signal modes' like WOLF, JASON and Bill's very slow BPSK modes.

If there is a significant performance gain for PSK08 compared to PSK31 on a noise LF band, remains to be tested. For static crashes which block the RX for a few hundred milliseconds, PSK31 may be just as good as PSK08...



Regards,
 Wolf  DL4YHF.