[amsat-bb] Re: 144 Mhz contact made using ISS as passive reflector

Robert Bruninga bruninga at usna.edu
Wed Dec 12 09:38:53 PST 2007

> ..."big" signals are small when they arrive up there .
> Assume 1kw and 20dB antenna gain... makes an ERP 
> of 100kw... once your signal is about 600km further 
> then you have -50dBm , so nothing to worry about .

Yes, although - 50dBm is a very "strong" signal... 100 million
times more power than the sensitivity of a good receiver, it is
still only one one-hundred-millionth of a watt. Couldn't even
harm a flea's eyeball.  And even a hamtronics receiver has over
100 dBm rejection just 15 KHz away.

So as long as it is not transmitted on exactly a channel
presently in use by an ISS receiver, then there is no problem.  

Or something like that.

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