You have to be careful about sweeping generalizations in this matter,
but I think I can add some measurable observations. PSK31 is by far
the most used digital mode for the average non-contesting amateur
radio contact. If one simply fires up the multiple channel
capabilities of Multipsk (or other similar software) and parks the
rig on 7035 or 14070, you will decode dozens of active QSOs in PSK.
If you do the same in RTTY mode and scan the RTTY frequency ranges on
40M and 20M during a non contest, you will often find NO RTTY stations
for periods in excess of 30 minutes. As a basic "rag-chew" mode, RTTY
is not dead but it is less used these days that Hellschreiber (sp?) ,
ALE, or MFSK16.
For contesting, I can affirm Bill's speculation. The contest logs
for RTTY versus PSK31 (or PSK63) are NO CONTEST, RTTY has far more
entrants per contest than PSK31. While RTTY does not perform as
robustly as some other digital modes, it is a tried and trusted mode
that contesters do not wish to give up.
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