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re: Bounce your signal off Mir (passive satellite)



   I have been trying "MIR bouncing" for more than one year now, but with no
   success at all. For theses tests, I'm trying to listen to the VHF transmissions
   of a french VHF transatlantic test beacon which beaming west. Beeing located east
   of the beacon, I usually don't receive any direct path signal, but I try
   to detect MIR echoes. No result ... I have to dig a little bit more 
   on the link budget :+))

If their beacon beams west, then they are probably using a gain antenna
of some sort. Terrestrial gain antennas (especially terrestrial omni gain
antennas) are useless for space communications unless the satellite is
close to the horizon.  One way they obtain gain is to avoid needlessly
sending the signal skywards.  If it's a transatlantic beacon, you can be
pretty sure not much is going into space unless they're hoping for meteor
scatter.  That's probably what's wrong with the link budget, negative 
antenna gain.

That doesn't mean that "MIR bouncing" won't work, but if you want to try
it, see if you can find an EME 'big gun' to be your source signal. Because
of the antenna reciprocity principle, such a station might stand a chance
of hearing you (but plan to use CW [even via PTT] as that's what they're
used to hearing).
			  -- KD6PAG (Networking Old-Timer, Satellite QRPer)
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