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Re: Two Sats



> Wouldn't you have less loss as you don't have to go 
> through all that atmosphere?... Of course we did it 
> on PCSAT and ISS...  :)

Yes, but communictions loss is almost insignificant going
through
Atmosphere except at some very high microwave frequencies.  The
Biggest loss in any comm link is the DISTANCE term.  It is 192dB

for going 40,000 km at 2.4 GHz.  192 dB is 10 to the 19th.  
That is, the signal is one divided by
16,000,000,000,000,000,000.

It takes power and/or a lot of antenna gain to make up for that.
Bob

> 
> 73s,
> de Eric KF4OTN
> 
> 
> Robert Bruninga wrote:
> >> If two sats like Hamsat (or Echo) were in orbit at the same
> > time and 
> >> could see each other ...
> >>
> >> Could User#1 uplink to Sat-A and then Sat-A would link to
> > Sat-B 
> > 
> > Its rather easy to evaluate that situation.  Look at what it
> > takes for a user uplink and downlink station just to hit the
> > satellite.  Now imagine that you are asking for all that
power
> > and gain antennas to be added to one satelite just so now
this
> > one satellite can work another satellite.  As you can see,
it is
> > pretty much impractical.
> > 
> > Bob, WB4APR
> > 
> > _______________________________________________
> > Sent via AMSAT-BB@amsat.org. Opinions expressed are those 
> of the author.
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> > 
> > 
> 
> 

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