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Re: EIRP for AO-10 ?

I have been experimenting with AO-10 over the last several months and can
offer some observations from my setup.  Using 10 Watts: 

I can make an acceptable SSB uplink with a pair of 8-element RHCP antennas
(quagi's), an effective 150 W EIRP, only when the satellite is under 11,000 km
and less than 10 degrees elevation.  CW is good out to about 16,000 km.

I can make an acceptable SSB uplink with a 14-element yagi (vertical, LP) out
to about 23,000 km, any elevation.  This is about 325 W EIRP.  I have made
contacts (well, 2 actually) out to 35,000 km, but my signal was barely above
the noise.  CW is good to apogee with this antenna, but now you are into
discussing the receive anenna as the limiting factor.  I suspect it would be
at least 3 dB better if CP and switchable, but haven't had the time to test it
yet (winter project after the HF contest season).

My best estimate right now, based on AO-10's current operating mode, at least
750 W EIRP would be needed to have reliable uplink capability and 1,000 W EIRP
is probably more comfortable--an FT-847 and a 15 dBi antenna would be a pretty
good system.  My current setup allows me to make opportunistic QSOs, but when
the sat is unfavorable--like this whole weekend (it's in the southern
hemisphere and FAR AWAY), I'm shut out.  Fortunately, there's the ARRL 160 m
contest to keep me out of trouble :-)

Jerry, K5OE
(PS:  My Christmas Arrow came in the mail--I can't wait!)
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