Re Shelby's comments ( and my previous after the RTTY Roundup ) on:
"COULD ALL CONTESTERS START (and end) ALL TRANSMISSIONS WITH A CR, PLEASE"
We're probably in most cases "preaching to the Choir" on matters of
"etiquette" or lack thereof.
However I also wonder if there is another gremlin working in some cases....
I saw some pretty convincing evidence that suggests that in some cases the
TNC/Modem/Soundcard is sending data too soon after asserting PTT (or VOX)
and the start of some transmissions are going into the bit bucket not into
the airwaves.
I would see something like this:
CQ CQ TEST DE XX0YY K
N1NB N1NB N1NB K
AB1CD K gobbledegook After My transmit ends and any other
good print an interval of decoding noise
garbleNB 123 123 BK while the CQ station to sorts out
calls and then comes back
Thus at least 3 characters are missing the 'N' ,"figs' ,'1', and possibly
'ltrs' plus any leading space,CR etc.
As I have been in recevie mode and decoding for some time in this example
it's not turnaround at my end, nor is the CQ station coming back before I
end my transmission (not that this ever happens HI HI)
I notice that the DXP38 has a parameter to control delay from PTT assertion
'til characters are send - default 20ms.
I don't see any obvious similar setting for MMTTY.
I'm not sure how a station can easily determine if this is a problem, but
wonder whether this is a contributor?
As a further note. For the first time I had both MMTTY and DXP38 looking at
the received audio. I used Writelog + MMTTY on my main machine running
MMTTY in FSK mode to my FT1000MP Mk V and the DXP38 to an old laptop. Each
feed from separate constant level AF out sources. Both indicated the
situation indicated above.
The purpose was not to do a formal comparison of the two demodulators, but
to allow me to do better in the contest.
There were times when one would clearly decode what the other saw as
gobbledegook and vice versa. There was no clear winner, but I did find a
number of times when I didn't need a repeat because one of them had clean copy.
CU in the WPX
73 Steve N1NB
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