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AO-40 Reception



Good Day To All,

I would like to share some information on Saturday's pass.  I would like
to agree and disagree with some of the comments of the past week.

Squint angle was very low for a long period of time on Saturday morning. 
There were not as many stations on as previously but no doubt that had
something to do with the Dayton Hamfest.  I managed to work a half dozen
stations with my simple set-up.  I have a Trans System converter with the
stub removed and a Drake with all the G0MRF mods.  Both are fed with a 21
turn helix with the grounded feed.  At a range of 58 to 50 K and a squint
angle of less than 5 degrees I could decode TLM and hear and work
stations in the transponder passband but it was a struggle.  I estimate
(by using a step atten in the IF line) that the beacon  was no more than
6 to 7 db out of the noise and the transponder signals were less than
that (perhaps about 3 db).   I could  hear the beacon with the Drake but
I could not decode any TLM and I could hear stations in the transponder
passband but could not copy them.

Obviously this supports the notion that the MMDS down converters and
simple antennas are not "good enough" and I agree until I consider what
"good enough" really means.  They can not compete with the dish antennas
and the high cost converters but I, and several others, are having QSO's
with them even if is is difficult.  As they say "if it were easy anyone
could do it".  Actually I think there is a place for the simple
equipment.  Certainly it's a start and my setup might be good enough for
the high gain antenna.  And even though the Drake doesn't quite make it
for me at the moment I want to continue to work with it.  I have in mind
putting a Down East Microwave preamp in front of it and I think it would
then be good enough.  I might also go for a quad array of helicies
instead of a dish.  Why?  I don't know.  I guess it's like climbing the
mountain.  You do it because it's there!

Good luck to all.

73's de Jess - W4MVB
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