[amsat-bb] Receiving FO-29 verses AO-7

B J va6bmj at gmail.com
Mon Dec 22 14:35:09 UTC 2014

On 12/20/14, Todd <superiortrading at gci.net> wrote:
> Hello:
> I am new to the Sat world and hope somebody can steer me in the right
> direction with a issue I have working FO-29. It seems I have no problem
> most times working AO-7's transponder and the SO-50 fm bird but can't
> seem to receive well with FO-29. I can hear the beacon (weak) but can't
> seem to hear my signal come back down. I am using a CW signal and using
> a Icom 706 and 746 rigs. SatPC32 is controlling both radios. Antenna is
> a cross polarized modified Cushcraft A6270-13S with the six meter
> elements left off and the UHF elements rotated 90 degrees. I have a
> Comet diplexer on the boom. I had problems with desense before rotating
> the elements. I have gone through everything I can think of using
> SatPC32 in calibrating but still can't tune the downlink CW signal.
> Yesterday FO-29 came by and I could hear my cw signal but seemed like I
> couldn't tune it in correctly (pitch). I don't have that problem at all
> with AO-7 and can tune the correct cw pitch and voice audio with no
> problem. I am wondering if the maybe the two radios are interfering with
> each other on those frequencies or at 435 the antenna still has some
> desense happening? The only difference is VU for AO-7 and UV for FO-29
> and 432MHz verses 435 for FO-29.


FO-29's downlink is known to fade once in a while, often making it
difficult to hear.  I haven't heard what causes it but it doesn't
appear to be related to illumination.  I've worked passes in daytime
and there are certain points in its path during when it become
difficult to copy.

Maybe the bird's wobbling and the antenna isn't pointed in a
favourable direction.


Bernhard VA6BMJ @DO33FL

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