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ERP "budget" for Oscar-10



Hello, all.  I am quite new to the list, and quite new to working
amateur satellites.  So far, I managed 3 contacts on AO-27 without
even realizing that it was not normal for the bird to be operational
in the middle of a Monday morning.  This, naturally, led to some
frustration when I couldn't ever seem to hit it again.  Now that I
understand its schedule better, I am not agonizing why I can't find
it in the sky on a Wednesday evening overflight.  Amazing how much
frustration can be prevented with a little knowledge.

But my real question concerns satellites that can't be worked with
a 5-watt HT and rubber duck or Arrow antenna.

More recently, I have, with considerable difficulty, worked only 2
stations on FO-20.  Fiddling with transmit and receive frequencies
while keeping one eye on the PC monitor and the other eye on the
rotor control, my third hand (?) keying the mic and my fourth hand
(?) pointing the antennas takes more coordination than comes easy to
me, but I guess that makes the couple of successes even more
memorable as well as more rare.

Last night I attempted to work Oscar 10, with nothing even close
to success, and I'm wondering if anyone can suggest to me what are
reasonable minimum uplink and downlink equipment to make the trip.
I am using a Yaesu FT-847 (50 watts output standard, but have a
"brick" for 2M that gives me 150 watts and one for 70cm that gives
me 100 watts), an older 11-element Cushcraft 2M beam, and a new
Cushcraft 719B 70cm antenna (19 elements on 13.5' boom), rated by
them as an optimistic 15.5 dbi.  I have no elevation ability at
present.  Last night, my tracking software indicated that Oscar 10
would be above my horizon (no more than 6.5 degrees) for over 2
hours, and I spent most of that 2 hours trying to detect its
presence, both with and without transmitting anything.  At times,
I heard a slight modulation of the background ambient noise that
could have been extremely weak SSB, but I really couldn't swear
to that.  And a couple of times, I heard definite CW activity, but
could not copy it well enough to tell if it was someone trying to
work the bird or someone attempting a terrestrial contact in the
satellite passband.  Listening to my own echoes wasn't much clearer.
At times, I thought that the ambient noise changed in a way that
was vaguely related to the noises I was putting into the mic, but
again the change was so subtle that I couldn't swear it was my
own signal coming back from Oscar 10.  At the time, my tracking
software said that the bird was about 20,000 statute miles out.

Is my station hopelessly under-equipped for this satellite?

John Toscano, KB0ZEV
Apple Valley, MN  EN34js

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