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Re: Making Progress at KM0T - A040



It appears that something goofy was happening this morning.
>From a report posted on the AMSAT-BB the beacon was
AWOL until 1230 UTC about MA-106.
As far as your antenna goes there are a lot of people using a BBQ.
I have one that is 39"x24".  I have screened it in with 1/4" mesh screen
and also extended the sides out to 39" with the screen so that I now have
a 1-meter dish.  I also added a circular G3RUH patch feed and have
my preamp mounted right on the patch feed, i.e., NO coax/pigtail.
Unfortunately I did not make any precise before and after measurements,
BUT,  the changes made a tremendous improvement.
The rib spacing on my BBQ was marginal so that is why I screened it in.
I am getting 3.5 Db of hot ground noise over cold sky when aimed at the
horizon.
(I could probably get a little more if I could aim the antenna at the
ground)
When aimed at a hot body, like my house, I get, 4 Db of noise over cold sky.
When aimed at the sun I get a 4.5 Db noise increase over cold sky,
at a solar flux of 145.
I hear 2.5  Db of AO-40 transponder noise floor at squints less than 10 when
the bird is
at full Apogee, i.e., 65,000 KM.
I would be very curious to see what you measure with your STOCK dish !!!!!
73
Rick


----- Original Message -----
From: "Mike A. King - KM0T" <scsueepe@mtcnet.net>
To: <amsat-bb@AMSAT.Org>
Sent: Tuesday, August 20, 2002 8:15 AM
Subject: [amsat-bb] Making Progress at KM0T - A040


Hi all,

First I would like to thank all the folks who got my first post a few weeks
ago on uplink antenna questions, I do appreciate all the info.  This has
been a very informative list.

The last week or so has been spent playing with NOVA and Uni-Trac with a
Yaesu G-5500 rotor.  The antenna I have is a BBQ dish - about 3' vertical
axis and a SSB UEK-3000 downconvter.  The feed on the dish says "Andrew" -
that hardline company, I guess I did not know that they made antennas.  All
the stuff is used and was to be in working order.

Anyway, most of the time has been spent getting the NOVA and Uni-Trac
software to talk to one another.  Also figuring out the config files, etc.

Well all appeared to be tacking except there was no AO-40 around.  So I set
my alarm for last night and caught the bird around 0645 UTC.  I found the
Middle Beacon, real strong, adjusted the antenna back and forth and and in
elevation to verify - sure enough it was a signal from space.  It was very
strong - about S-5 with a bit of QSB.

Now, I know this may not be a big deal, but its the first time I have every
heard a sat!

Then the beacon seemed to just cut off about 0654 - which coorelated with a
"MA30"?  I looked up on the Web and found that this was a scheduled turn off
of the S2 beacon.  More proof that I actually heard AO-40?

I also at the same time tuned the band, no ham signals found.  When
investigating on the beacon turn off- I notice the transponder schedule.  No
wonder it was quiet.  It said it would turn on at like MA-76.

So I hit the sack for a bit and got up around 4 am local - nothing heard at
all - no beacon or hams on the bird.  Went outside, did not seem to be
pointed into anything, a mystry?  I think I recall this was around MA-90 but
not sure.

Then got on to listen this ealy am and heard the beacon again, but no ham
signals, this was around MA-97 to MA-103.  The beam heading was 7 degrees,
pretty much on the horizon and  NOVA ranged AO-40 at 62278 km.  I still did
not hear any ham stations or any other beacons other than the middle beacon.
This beacon was much weaker than what I heard around 0645 UTC.

So the question is, It appears to be working, but no hams to be heard?  Is
the middle beacon that much stronger than anyone else?  Or could it be there
really was nobody on?  (I doubt it).   Or is the fact that I heard something
at all a good thing.  I guess I dont know what else to do with the RX
system.  Perhaps local clutter, just not sure.  Not sure what else I need to
do as far as improving the downlink except a better or bigger dish?

Any comments appreciated.

Also - is Uni-Trac a bit difficult to get running?  I found it to be a bit
taxing.  Or am I the only one?

73

Mike - KM0T en13vc
www.qsl.net/km0t



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