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Re: Parabolic AB Query

-bb posted for "others" also.

I don't know the LO frequency of the  Parabolics downconverter.  The output
for AO-40 is "around" 145.300 to about 145.370 depending upon doppler, on my

I run QuikTrak 5.02 here.  It controls the antennas with KCT and Yaesu 5400,
and it gives me the correct doppler frequency without having to do any math.
Depending upon the "freshness" of the keps I put in, and the setting of the
clock, usually the frequency indicated by QT 5.02 is within .0010 of what
shows up on my FT 736R.  I have not checked calibration on the FT-736R.

If you are trying to hear AO-40 for the first time, it's tough because you
are playing with two variables, frequency and antenna pointing.

My suggestions:
1.  Make sure your antenna is pointing towards AO-40, + / - 5 degrees in
azimuth, elevation does not seem to be that critical, but keep it as close
as possible.
2.  Listen around MA= 230-240, etc.
3.  Tune around until you find the signal
4.  The signal should be over S9 at this time.
5.  Make sure there are no trees between the dish and the satellite.
6.  My 3 ft dish outperformed my 10 ft dish on Saturday, when the 10 ft dish
had to look up through the trees and my 3 ft dish was in the clear.(P.S.:
The trees will be gone today).
7.  To determine if your system is working at all, try a couple of these
tricks:  Attach the antenna to the rig while the rig is on and notice if
there is a noticeable increase in receiver "noise". There should be.  Put a
large glass of water in the microwave oven and run it for about 2 minutes
while listening to the receiver.  My oven is about 75 ft from the 2.4 GHZ
antenna, and I hear the "pulsating" signal quite well.

IMHO, the Parabolics AB downconverter is about as good as they come.
Nothing here; (2) Trans 3733's and a Cal Amp come close, unless when they
are connected to the 10 ft dish.  Because the Parabolics AB works so well
with the Phillips SPG 36, I haven't moved it to the 10 ft dish, (yet).

BUT, I have heard AO-40 with good signals on the 3733 with the dish that
came with it, the 3733 with a solid 39 inch DSS dish and, of course,  the
3733 and dipole on the 10 ft dish.

What type of antenna are you using?

Bob,  AC9R

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