I sent this privately to John, but he felt I should share.
This is in response to John's message as well as the W2HOS bulletin received
today.
What got PSK31 started is simple: FREE SOFTWARE. And W2HOS always mentions
that in any discussion. He is an evangelist on the topic of replacing RTTY
and ignores the fact that many of us have transitioned to FREE RTTY software
also.
The reason that you hear PSK31 all of the time is not its superiority -- it
is just where the guys on 75m that wanted to try something else went BECAUSE
IT WAS FREE.
His example of how PSK63 would be great for contests because you could say
"hi there and goodbye" in addition to the exchange really is ridiculous. If
you give AA5AU twice the sending speed he is going to use that time to work
more stations -- not to discuss his life.
The supposed power advantage to PSK is overstated. They ignore issues of IF
bandwidth, receiver dynamic range, phase distortion on bad paths, and
frequency stability. MMTTY will copy into the noise. Sure PSK has a few db
of advantage but the QRP thing is all hype. In addition, of course, if we
go to PSK63, any serious contestant is going to run as much power as his
power class allows. So the argument that you can only run 5 watts will go
to pieces.
I don't even want to go into macros. RTTY used to have plenty of them and
when I first got back on the air again in 1996 the advent of computers had a
lot of completely canned RTTY QSO's. Heck, even back in 1966 all of us had
paper tape readers and brag tapes. At least they were interesting because
the motto was "RTTYers build". So there was some fascination regarding how
a station had interfaced with their RTTY machine and which machine you'd
actually gotten working. How a bunch of canned messages saying that you're
running a Mark IV with Rig Blaster and an old IBM laptop is interesting is
beyond me!
I've tried hard to work some of the PSK contests. Not a lot of fun. Long
exchanges, overly sensitive tuning, and unexperienced contestants. And
forget a PSK pileup -- even more chaotic than the RTTY ones. Lastly, in a
contest situation the theory of running 2.1khz bandwidth and sorting things
out in the audio card and clicking on multilple "tracks" from a waterfall is
not going to work. The strongest signal in the bandwidth is going to
capture the AGC and the weak ones just fade away. The solution, of course,
is to defeat the AGC by turning down the RF gain -- but the real solution --
and one that will let you use this wonderful bandwidth advantage -- is to
crank your IF selectivity down to 50hz. Of course, when you do that, you
lose all of the AFC advantages and the like that allows the PSK guys to talk
using equipment that doesn't have the stability to maintain a plus or minus
5 Hz frequency stability. Heck -- even my Taos Icom Pro has problems
because the transmit and receive are offset by something like 10 hz. When I
work PSK I have to use a transmit offset continuously for this reason.
Picture a whole lot of contesters running AFC and NET with transceivers that
have a small offset problem or a bit of frequency drift.
Imagine 20 of the biggest RTTY signals all crammed into one 2.1 khz
passband. What a mess.
And to what end? What is it that makes these guys try to push "their" mode?
I'm always willing to try something new and I'll be happy to experiment with
PSK63. But to be honest, what makes a mode are those that use it -- its
advantages are only a small part of the equation. Ragchewers like PSK31,
contesters use RTTY. Why does one or the other have to win the discussion?
Use the mode you like and leave those of us who don't like it alone!
Looking forward to watching the discussion.
73,
Mike WA0SXV
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