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RE: Geo Opportunity



>With all the calculations ive done, on all the
>different band i tried, a Geosat
>at ~35k klm
>with a 0dbi gain RX antenna would not be useable with
>anything less then an EME
>class station.
>I may be wrong but i dont think so. 


Only the moonbouncers would be making SSB contacts but
I think the CW and PSK31 ops could be happy, 'tho my
back-of-the-napkin calculations could be wrong. 
Assuming a 2 metre downlink, a 1 dBW ERP (LP) from the
satellite and a 1.8 wavelength long CP yagi in a quiet
location with a good preamp:

satellite ERP 1dBW
path loss -168dB
polarization loss -3dB
transponder loading -10dB
station antenna gain 13.7 (dBic)
antenna/system temperature 500 degrees k
receiver bandwidth 2.7 kHz

10log 1.38E-23 * 500 * 2700 = -167 dB noise power

I come up with a 1dB s/n ratio.  I guesstimated the
system noise temperature using the VE7BQH antenna
table at:

http://web.wt.net/~w5un/144gt1.doc

and then I doubled the Ta.



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