On Wed, 11 Mar 2009 06:41:55 -0700, Tim Shoppa wrote:

Class C operation seems very well suited to HF CW operation. At least if
the resulting envelope looks "nice" by ARRL handbook definition of
keyclick reduction, I guess.

But is it good enough for RTTY?

How about for PSK-31? Olivia?

What I've got is an old Eico 720 (Novice 75W-class transmitter biased
for deep class C, for those too young to remember) that I currently use
for CW, but would like to try out for RTTY or maybe PSK-31 by feeding
appropriate waveforms into the "VFO in" jack. My gut feeling is that
RTTY would be OK but don't really understand how class C will mess up
the PSK-31 waveform or introduce intermod that will make the resulting
spectrum broader than necessary.

The Class C stages will clearly fail the usual SSB two-tone testing but
what is a more appropriate test to say that it's good enough - or not -
for PSK-31?

Tim N3QE

If the signal has a constant envelope then it'll be fine with class C.

RTTY should be fine, I don't know about PSK-31 or Olivia.

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