Some excellent points Mike. Your comments " The strongest signal in the
bandwidth is going to
capture the AGC and the weak ones just fade away " is perhaps the most
important issue. The September PSK63 contest that I have scheduled will be
an interesting tests. In the CCCC PSK contests that I ran , the impact of
strong signals and AGC capture was a difficult issue. I even had a request
from two Brazilian hams to disqualify another Brazilian because they could
not work anyone while he was "dominating" the band.
PSK63 has some promise, that is all, it is not a threat to RTTY contesting .
As for PSK31, it is clearly more popular for digital rag chewing than RTTY
and that is exactly what Peter Martinez had in mind when he developed his
amateur radio version of PSK.
I hope that many RTTY contesters will have an open mind and join the
September PSK63 Contest. The comments afterwards will be helpful in
determining if PSK63 has any future.
For info on the contest go to
http://www.netsync.net/users/obrienaj/quickpsk.htm
K3UK
----- Original Message -----
From: "Mike Mellinger WA0SXV" <wa0sxv@mellinger.com>
To: "'WA9ALS - John'" <wa9als@starband.net>; <rtty@contesting.com>
Sent: Monday, May 19, 2003 9:23 PM
Subject: RE: [RTTY] Death of RTTY?
> 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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