[Moon] Reply to Peter SM2CEW

[Doug Allen]

Peter, SM2CEW, describes JT-65 in a way that makes me question the validity
of JT-65 contacts, but I am not competent to discern whether his software
description is accurate. I have operated meteor scatter for 43 years. For
almost a decade during the 1990's, I operated conventional CW EME with high
power and a four 5 wl 2M yagi az-el array. For several of those years, I was
editor/publisher of the "EME Newsletter" which had subscribers from over 30
countries. The EME operating procedure we all used was adapted, I think,
from meteor scatter operating procedures, and was uncontroversial. I had
little reason to publish anything about it during those years.

I first used digital high speed meteor scatter in the early 1990's with
software that preceeded Joe Taylor's WSJT, and I have used WSJT FSK-441 from
the beginning, making the first meteor scatter contacts with it, I believe,
from Mexico and from Belize in the 1990's. I think FSK-441 is a wonderful
advance in technology making meteor scatter communication possible with
modest stations at any time. I continue to use it and think Joe Taylor has
made a wonderful contribution to amateur radio. WSJT is a free program used
by thousands. Thank you Joe!

Recently, I have made a number of JT-65 EME contacts with 600 watts and a 2M
5 wl yagi from my new SC QTH. The decoding sometimes did not convince me
that I had made a solid contact. Let me give a related observation. Several
times I ran JT-65 in AUTO mode with message # 6, "CQ W0AH EM85," BUT WITHOUT
ACTUALLY TRANSMITTING. Without transmitting, I have received up to a half
dozen calls with signal reports from different stations in one hours time!
Obviously, JT-65 decodes a lot of misinformation from white noise. I will
leave others to evaluate the significance of this observation, but I wonder
if Joe might not "tighten" the decoding thresholds a bit in order to make
the software receive parameters more analogous to the aural reception
parameters of conventional CW EME, thus addressing Peter's criticism while
at the same time satisfying, I would hope, the many dedicated users of the
software?

Doug Allen W0AH EM85  Inman, SC


-- 
Doug Allen
Here's a new webpage I'm working on:
http://DougW0AH.googlepages.com/home

And here's the 73 CIRCLES blog-
http://73circles.blogspot.com/
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