You're hearing MFSK16 (Multi-Frequency Shift Keying)I'm sure with an actual
text-throughput of about 31.25bps. I did some experiments with a fellow in
Australia on 20m running RTTY, PSK31, and MFSK. We could almost make a
contact on RTTY running 100watts (band conditions weren't that great and I
was running a dipole at 15ft at the time) but only bits and pieces, with
PSK31 at 25w I had about 75% print but any QSB took him out completely.
MFSK16 on the other hand was perfect 100% copy, even when the signal dropped
just above the ambient noise on the waterfall display. I've run MFSK
aeronautical mobile with some great results on occasion (I'm usually on
PSK31 though), seems to get through static noise pretty well.
MixW also lets you send files and pictures via MFSK, although it's not
technically legal as per Part-97 for US ops; supposedly they're going to
change that rule (maybe already have). I've watched some guys send pictures
though, and it works really well at a fraction of the bandwidth of SSTV.
Occasionally you'll hear THROB between 14070 and 14080. There are a couple
of different width THROB modes, and they all sound strange (but they do work
pretty well). You can download a demo version of MixW from mixw.net and
listen to the different modes.
73 - Scott, N4GVA
-----Original Message-----
From: rtty-bounces@contesting.com [mailto:rtty-bounces@contesting.com] On
Behalf Of Jerry Pixton
Sent: Monday, May 31, 2004 7:03 AM
To: rtty@contesting.com
Subject: [RTTY] signal on 14.080?
Anyone,
This old dog is trying to learn new tricks. What modulation are the
signal(s) that generally are around 14.080?
It sounds to me as if it where a rtty signal, that is I only hear several
tones, the shift seems to be 170 hz but the baud rate is much higher. I
have tried to decode it at other baud rates and I have tried ASCII codes
but no print.
It is not bursty like AMTOR, which often is on this frequency, although it
does seem to have short transmissions - I just switch to a new decoder and
it is gone for a while.
Jerry, W6IHG
------------------------------------------
Dr. Jerry R. Pixton, PIXOS Designs LLC
http://www.pixos.com/designs/RadioTuner/
jpixton@shentel.net
------------------------------------------
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