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Help with L1 uplink on AO-40



Hello,

I am debugging my ground station for AO-40 and was wondering if someone who
might have been using the L1 uplink tonight could tell me how well it was
working? I was just barely able to hear myself on the downlink, however I
could hear the beacon and many others well above my signal level. I am
assuming that my receive setup is OK since I could hear myself (in the
noise) and others (well above the noise) and the beacon (very strong).

At the time of my experiment (1/5/03 05:00 - 06:00 UTC) the squint was about
12 degrees (assuming I set Nova up correctly).

I am thinking that I have a serious uplink problem. I have two 12-turn-helix
(RHCP) phased for approx 17dBic of gain, with about 60 feet of LMR-400
ultra-flex and a SSB 80watt amp feeding the system. I am loosing 3.4dB in
the cable run and according to my directional wattmeter I am getting 2 watts
reflected. Could something be wrong in the phasing that wouldn't show up as
a reflected energy? I am thinking of swapping the phased helix out and
replacing it with a 22 element yagi just to help isolate the problem.

I only plan on running enough power to get my signal 8dB below the beacon,
but right now, I am way below that.

How much power are others using for their L band uplinks? And what antenna
(and gain) are you using?

Any thoughts?

Joe
k6sat
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