Re: [amsat-bb] Bounce your signal off Mir (passive satellite)

[Roy Welch <rdwelch@xxxxxxxxxx>]

I have not tried "Mir Bouncing" transmissions.  However I have noticed when
there was a lot of ground activity trying to contact MIR that if I just
tracked MIR and had my  squelch barely closed, it would open noisily for
the duration of a MIR pass.  I feel that with MIR having a nice resonant
antenna on the outside that it was being excited by all the on-frequency RF
from the ground and was re-raidiating it back, although ever so weakly.

Jean-Louis.RAULT@tcc.thomson-csf.com wrote:
> 
> I leave in a valley (the name of my street is Valley Road!)
> and am definitely NOT in line of sight of a 144 MHz beacon which
> is located at about 280 miles from home.
> More than 10 times per hour, the signal becomes readable
> for a few minutes, with a nice Doppler effect (shifting from + 300 Hz
> down to - 300 Hz).
> The same phenomenon occurs with a short waves broadcast transmitter
> located about 150 miles from home. The 21 MHz ground wave is just
> readable but many + or - 40 Hz Doppler shifted strong sigs appear.
> I use the Spectrogram FFT software to clearly analyse
> and display the echoes. (Bmp waterfall pictures showing nice "S shape"
> records are  available on request).
> Where do these echoes come from ? From the airplanes flying in
> the Paris area.
> 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 :+))
> 
> Cheers
> 
> Jean-Louis F6AGR
> 
> > -----Message d'origine-----
> > De: Robert Rice [mailto:rcrice@netropolis.net]
> > Date: vendredi 21 janvier 2000 04:34
> > Cc: amsat-bb@AMSAT.Org
> > Objet: Re: [amsat-bb] Bounce your signal off Mir (passive satellite)
> >
> >
> > In a very small way, I've done this terresterially.
> >
> > For some time several years ago I accessed a packet node that
> > was directly
> > east of me,  but blocked by many buildings in the medical
> > center 10 blocks
> > down the street to the east by pointing my 3 element beam due north at
> > downtown Houston and doing building bounce.
> >
> > Amazed the daylights out of me when I first did it.  Took me
> > entirely by
> > surprise... until I thought about it.
> >
> > Rob Rice
> > WB5PKN
> >
> >
> > ----
> > Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
> > To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org
> >
> ----
> Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
> To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org

-- 
73, Roy

Internet: w0sl@amsat.org
Home Page: http://home.swbell.net/rdwelch
----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org