[amsat-bb] Re: FO 29 help

K5OE k5oe at aol.com
Sat Apr 23 12:08:12 PDT 2011

It sounds like you are hearing a "reflection" of your signal, not the downlink from FO-29.  This is a common malady associated with 3rd harmonic interference on mode J (V/U) satellites.  Try this on a pass that will reach at least 30 degrees above the horizon:
1.  Turn HRD control of your TS2K off
2.  Set your uplink at 145.950 CW
3.  At AOS you should hear the beacon about 8-10 kHz above the beacon freq of 435.895 (about 435.904 MHz)
4.  Tune your receiver to 435.850 plus that same delta from beacon (about 435.859 USB).  You should be able to tune your receive and hear your CW dits (clearly). 
5.  Zero beat the CW dits on the low side, switch to LSB and you should be exactly on frequency and can turn on TRACE and go anywhere in the passband.  

If you have auto-Doppler turned on in HRD, your program should do the same thing as this manual procedure.  

You should be able to hear yourself.   If not, Google the diplexer fix for the harmonic problem.

>From the center of the passbands, whatever the UHF Doppler shift is, the VHF Doppler will be approximately 1/3 in the opposite direction.  This is a helpful rule for finding your downlink manually.

Jerry, K5OE

-- original message --
Good morning,

Since putting up the Elk on a rotor (fixed el +- 25 deg), I decided to try
some linear birds.

I have tried FO 29 about 3x but seem to have some issues. I am using TS-2000
in SAT mode with HRD Sat program.
Up: 145.9  LSB
Dn: 435.8  USB

I am clearly able to track the bird with doppler as I can hear the CW beacon
through the entire pass (switching back and forth). I can also TX into the
bird and hear my signal coming back duplex. However, what is coming back is
my voice signal but totally unintelligible. Also, I have heard no other
stations on these passes.

Am I doing something wrong?

Tnx for any help

Ted, K7TRK

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