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AO-51 fading?

Thanks for taking the time to read this.  I noticed during the last two
periods that AO-51 was in mode L/S (but also when in V/U) significant fades,
at least for my signal.  There are periods when I sound solid into the
satellite and then periods when I hear nothing.  Others who are on L/S
mention to me that my signal is on the weak side.  On Mode V/U it is too
much of a free for all to get a signal report.

As a check of at least my V/U set-up, I tried FO-29 and found my signal is
solid for nearly the whole pass.  I conclude from this that at least the V/U
side of my station is in good shape.  

My station consists of an FT-847 configured the following way:

L band uplink: 435 MHz connector on radio >> 3-ft 9913 >> N position switch
>> 3-ft 9913 >> IF to Parabolic 1268 MHz uplink converter >> ~3-ft 9913 >>
bias tee >> 75-ft of RG-8 cable >> 15-watt mast mounted PA >> 6-ft of 9913
>> 15-turn helix RHCP antenna.

S band downlink:  60-cm prime focus dish illuminating a 3.25 turn helix >>
6-ft 9913 >> Parabolic S-band down converter >> 50-ft 9913 >> bias tee
coupled to one leg of an N position switch >> 4-ft 9913 >> 144-Mhz connector
on the radio.

V band uplink:  from the V/S N position switch >> ~50-ft 9913 >> Mirage KP-2
preamp >> 12-ft 9913 >> KLH 144-22 CP antenna (RHCP only).

U band downlink:  from the U/L N position switch >> coupler to bias tee >>
~50-ft 9913 >> Mirage KP-2 (70-cm) preamp >> ~12-ft 9913 >> Gulf Alpha 16 el
CP antenna (RHCP only).

Comments are welcome particularly of my L/S set-up.  Before you comment on
the RG-8X cable on the L band side, Parabolic requires attenuation of RF to
1/4 watt feeding the PA. RG-8X does the job nicely.

Kevin Smith
AMSAT 29705
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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