[amsat-bb] Re: Not hearing S-band on AO-51

[Andrew Glasbrenner]

Have you checked your downconverter with some sort of frequency standard to 
make sure it is where you think it is? Also, are you tuning for the +/- 50 
khz of doppler shift? Both of these are common pitfalls with Mode S on 
AO-51. The downlink is very strong, Sunday night I copied the downlink thru 
the shack window with my downconverter and corner reflector.

Good Luck,
Drew KO4MA

----- Original Message ----- 
From: "Michael Tondee" <mat_62 at netcommander.com>
To: <amsat-bb at amsat.org>
Sent: Thursday, September 14, 2006 8:01 PM
Subject: [amsat-bb] Not hearing S-band on AO-51


> I've been trying to get a handle on my S-band receiving setup for a
> couple of months now. It seems when the bird has been in V-S mode that
> I've had one problem or another that hasn't allowed me to test it. I
> don't have an L-band antenna up at the moment so I thought I would at
> least listen to some passes the past couple of evenings  to see how my
> receive would work.
> I have a AIDC 3731 downconverter and a small BBQ-grill dish on my Az/El
> rotator system. The IF of the downconverter is at 123 Mhz.  I built
> another converter that was featued in the AMSAT  Journal awhile back.
> The purpose of this converter is to further reduce the 123 Mhz output
> to  6 meters where I can feed it into my TS-2000X. Unfortunately I
> haven't heard anything with this setup. I've had some near overhead
> passes and once my dish gets above about 30 degrees or so it is pointing
> at clear sky. I thought maybe my homebrew  converter was to blame so I
> dug up an HT that will receive directly on 123 Mhz. Still nothing.
> I can hear the noise level increase and decrease if I cut power on and
> off to the  downconverter so I assume it's working. Could I be wrong in
> that assumption?
> The other thing is that it's been kind of rainy and overcast here the
> past couple of evenings. Would this affect my reception?
> I don't know what I should be trying here. It's pretty new to me. I know
> a BBQ grill dish isn't the best antenna but it seems to me it should
> work ok considering people hear the bird with this same downconverter
> and a small corner reflector  plus an HT.
> Any ideas or suggestions out there?
> TNX and 73,
> Michael, W4HIJ
> AMSAT #  36017
> _______________________________________________
> Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
>