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Re: 144 Mhz contact made using ISS as passive reflector



Already discussed on the MoonNet reflector:

Subject: Re: [Moon-net] ISS communicaton  NOT a GOOD idea !!!!

Hi Steve ,

Even our "big" signals are small when they arrive up there .
Assume you use 1kw and 20dB antenna gain , this makes an ERP of 100kw or 80
dBm ERP, once your signal is +/- 600km further then you have about -130dB
less power due the path loss (on 144MHz)  , this means that your signal
arrives at ISS with a level of -50dBm , so nothing to worry about .


Best regards,
Kenny ON4DPX


At 07:49 PM 12/11/2007, Greg D. wrote:

>I thought of doing this back in October, when all the Sputnik-1 / 
>early satellite discussion was happening.  Echo-1, and all 
>that.  But, I would think that NASA (if not the crew) would frown on 
>a bunch of folks on the ground hurling a few megawatts EIRP at their 
>home in outer space.  If Bob had to have a bazillion levels of 
>safety in place for the little PCSAT-2 transmitter, I would think 
>this would be right up there in the safety category, no?
>
>I haven't done the math yet...  Are we far enough away that 1/x**2 saves us?
>
>Greg  KO6TH
>
>
>----------------------------------------
> > Date: Tue, 11 Dec 2007 11:32:50 -0800
> > From: bob@evoria.net
> > To: amsat-bb@amsat.org
> > Subject: [amsat-bb]  144 Mhz contact made using ISS as passive reflector
> >
> > http://www.southgatearc.org/news/december2007/bouncing_signals_off_iss.htm
> >
> > Congrats to the DF2ZC and DH7FB on making a CW contact using
> > the ISS as a passive reflector!
> >
> > It's interesting that in the article Bernd discusses the problems
> > with using PSK due to doppler, as well as manually having to
> > set az and el.  It seems to me that a couple of well equipped
> > computer-controlled earth stations should be able to do this using
> > One True Frequency principles with PSK.  Wish I had the equipment
> > to give it a try.
> >
> > Bob - AE6RV
> > _______________________________________________
> > Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author.
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>
>_________________________________________________________________
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73,
Ed - KL7UW
======================================
  BP40IQ   50-MHz - 10-GHz   www.kl7uw.com
144-EME: FT-847, mgf-1801, 4x-xpol-20, 185w
DUBUS Magazine USA Rep dubususa@hotmail.com
====================================== 

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