Leigh L Klotz, Jr. wrote:

> I think MARS adopted it so it has some momentum there. Are they still
> using it?

Increasingly so.  Since most traffic is pre-prepared the fact that
keyboard interactive has some lag isn't considered a big deal.  The
region six AF digital net is pretty much an all MT63 show, and word has
it that it's increasingly the most common mode on the Navy side as well.
 It's starting to leak onto TRANSCON, so there's no doubt that
acceptance is spreading.

Comparing modes is always a bit dodgy thanks to the affects of
environmental conditions, but a fellow MARS operator did a comparison of
MT63 vs. various Olivia submodes a while back using a short but still
valid EEI message.  His findings for said message:

MT63 1kHz: 1 min 10 sec
MT63 2kHz: 37 seconds
Olivia, 32 tone, 1kHz: 4 min, 1 sec
Contestia 4 tone, 500Hz: 1 min 14 sec
Contestia 8 tone, 1kHz: 50 sec
Contestia 4 tone 1kHz: 31 sec
Contestia 8 tone 2kHz: 25 sec
Contestia 4 tone 2kHz: 19 sec
RttyM 8 tone 2kHz: 13 sec
RttyM 4 tone 2kHz: 10 sec

Naturally S/N degrades for reduced block size.  MT63 isn't too bad with
-8dB S/N minimum, and Contestia 8 tones, 1kHz isn't a slouch, either.

One of these days we'll get around to observing how these things work
under differing conditions and as they degrade, but it hasn't percolated
to the top of the to-do list yet.

-- 
Chris Kennedy
[EMAIL PROTECTED]               AF6AP
http://www.mainecoon.com        PGP KeyID 108DAB97
PGP fingerprint: 4E99 10B6 7253 B048 6685  6CBC 55E1 20A3 108D AB97
"Mr. McKittrick, after careful consideration..."

Reply via email to