Skip apparently doesn't subscribe to the RTTY reflector. He sent me the
comments below privately, but later gave his permission to copy to the list:
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Hi John,
Jim, N2HOS, forwarded your comment on his Gazette article to me, and I'd
like to offer my own comments.
"There is plenty of room for both, but RTTY has already given up this
battle. Peace!"
Taken in the whole context of Jim's editorial, I interpreted this not as
RTTY has really lost anything, but that PSK31 has earned the right to be
recognized as a good mode for ragchewing, so that is why it is so prevalent
outside of contests. In fact, PSK31 is definitely too slow for contesting,
and that is why I tried to provide a faster version, PSK63, as an
alternative to RTTY.
"1. PSK63 has some attributes that should be attractive to digital
contesters - Fast (100 WPM) and narrow bandwidth to name a couple. They
also claim much better participation, judging from current PSK31 use. Thus
I think we need to evaluate it for its strengths and weaknesses and not just
stay with our heads in the sand saying "RTTY FOREVER [no matter what]".
John, I really appreciate your open-minded attitude in this regard. I have
merely tried to provide a new tool which I hope will be useful for digital
contesting. Like you, I see no reason to try to defend either RTTY or PSK63,
because both will be available. It is going to take a long time for PSK63 to
become a significant contest mode, because there are currently so few on
PSK63 to contact! Even at that, if PSK63 lives up to its promise as a
contest mode, I forsee a mix of PSK63 and RTTY during contests, and
whichever mode proves to be more advantageous will eventually become (or
remain) the most popular. PSK63 is not going to benefit the super station
with the strongest signal who camps on a few frequencies and rapidly works
all those who call him. Rather, it will help the others who roam the band
looking for new contacts. In this regard, being able to pick and choose out
of a collection of as many as 24 signals in one place should prove to be an
advantage for PSK63.
"2. Veteran RTTY contesters need to evaluate PSK63 for another reason -
RTTY
contesters have experience! I would value the opinions and experience of
veteran RTTY contesters over that of novice PSK63 contesters."
Definitely! I have been trying to figure out how to find willing RTTY
veterans to try PSK63 and pass along their impressions, good or bad. PSK63
will not provide its potential benefits unless it is evaluated, found to be
beneficial in ways that RTTY may not be, and then truly embraced by the
majority of RTTY contesters. The idea is not to promote one mode over
another, but to offer an alternative to RTTY and let the operators decide
which mode they prefer, or just use both.
"Jim points out that there are "wall to wall" PSK signals when there are no
RTTY signals (unless there is a contest). I could counter that yes, there
are lots of PSK signals, but there are also a lot of over-driven signals
endlessly sending macros back and forth to multiple stations at a very slow
rate (PSK31). That's not a great criticism, however - Some AFSK RTTY
signals are overdriven too."
I guess I really do not get the point here. PSK has a 3 db S/N advantage
over FSK in the same bandwidth, but necessitates keeping things linear. To
keep things linear, you need to run half-power on PSK63 compared to RTTY, so
you are back at the same place regarding S/N, but the transceiver runs
cooler, and using PSK63 instead of FSK63 has the advantage that when you are
not typing, it is indicated by the familiar "railroad tracks" of PSK31.
FSK63 looks the same on the waterfall whether or not you are are typing.
This is a small distinction, but a useful one. The better transceivers can
run full power without overheating, and some, like my two old IC761's, can
run full power and stay linear, so in that instance, PSK63 has a 3 db (twice
power) advantage over FSK63. Overdriven signals are usually generated by
those new to the mode, and those operators soon learn to keep it linear by
just running at a lower power level. It is the narrow bandwidth of PSK63
compared to RTTY that makes it p
"'ll stop here - I just wanted to put something out here and hope for some
discussion. I'd like to see some knowlegeable and experienced RTTY
contesters evaluate PSK63 so that we will have some feedback from our own
community. Hopefully some of us will be able to participate in the first
PSK63 contest in September. I suspect that, once again, RTTY will come out
on top. I just hope that our guys will jump in and evaluate PSK63 and not
let moss grow on our keyboards in the name of tradition. Have faith - RTTY
is a tradition because it's passed the test of time and several new modes."
John, again, I wish to thank you for such sage advice and openmindedness. I
think it does not matter which mode "comes out on top". 850 Hz shift RTTY
was used long before 170 Hz shift RTTY, and enabled us to use frequency
diversity to reduce the error rate. In the same way, 170 Hz shift RTTY will
survive more often over the polar path than PSK63, even when PSK31 is
totally unreadable. We don't know yet how PSK63 will do, but in that regard,
RTTY will always have a better chance of success because it is wider and the
doppler shift has less effect on the overall signal. The latest alternative
to both better polar path performance and weak signal performance is MFSK16.
So, there are many tools these days to select for each job. It is not
necessary to use just one, but to use the tool that does the best job for
your desired task.
If PSK63 proves to be at least as much fun and effective to use for
contesting as RTTY, then many will use it. As I told Jim, you can't listen
to PSK63 for very long, but RTTY is music to these old ears, and even if
PSK63 becomes popular for contesting, I will still be able to find a group
of old friends on RTTY, turn up the volume, and bask in the sweetness of old
faithful!
"As for "already given up this battle" - Jim, I respectifully think not!
;-)"
I think there is no "battle" - just individual preferences...
73, Skip KH6TY
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