[amsat-bb] Re: S band and Eagle: an appeal for a higher leveldiscussion

i8cvs domenico.i8cvs at tin.it
Sun Sep 10 19:11:17 PDT 2006


----- Original Message -----
From: "Greg D." <ko6th_greg at hotmail.com>
To: <amsat-bb at amsat.org>
Sent: Sunday, September 10, 2006 8:40 PM
Subject: [amsat-bb] Re: S band and Eagle: an appeal for a higher
leveldiscussion

> If 2.4 ghz pollution is going to be a problem for stations on the ground
who
> are looking up (and away from) the noise, how is it possible that a
> satellite in the sky looking down on half of a planet's worth of 2.4 ghz
> noise, is going to be able to pick out one earthly station over the din?
> This is totally backwards in my mind.

> Greg  KO6TH

Hi Greg, KO6TH

It is possible !

During the test of 23 Feb 2003 AO40 was looking down on half of the
planet's using his S1 high-gain dish connected to the S1 RX worth of
noise on 2400.475 MHz and was able to pick out G3WDG and i8CVS for
the first experiment on S/K band in wich an amateur satellite was
succesfully tested the first time to receive over the dim an uplink at
2400.475 MHz

So it is totally backward in my mind why the S band is considered a sewer
three years now from the above test.

If you look at the following page you have the complete report written by
G3WDG and a wave-file showing how clean where both signals over the
noise on SSB

http://www.g3wdg.free-online.co.uk/s_ktest.htm

----------------------------------------------------------------------------

Quoting Stacey E. Mills W3SM
[amsat-bb] AO-40 Update, 2003-02-23

Two tests were performed on AO-40 today.

The second test involving the S-band receivers was completely
successful.  Extremely strong downlink signals were possible using S-band
uplink to K-band downlink.   Charlie (G3WDG) phoned me and I heard
beautiful downlink signals from his ~5 watt uplink to S1.  S2 was also
active, but because of its higher, less common frequency (2446 MHz), it may
not have been tested.  The S1 Rx uses the S1 Tx high-gain dish, and the S2
Rx uses the 5 turn helix used by the S2 Tx, so signals would not be as
strong through S2 at low squint.  More information will undoubtedly be
posted on this by the participants, but special thanks to Charlie (G3WDG),
Mike (N1JEZ),  and Dom (I8CVS), and any others who participated in this
successful test.

The S1 Rx can certainly be listed as fully functional.  We will await
further testing/info. on the S2 Rx.

--W4SM for the AO-40 Command Team
----------------------------------------------------------------------------

Quoting Charlie G3WDG
[amsat-bb] AO-40 S/K Test

All,

I have posted some info on the tests here, including some recordings of
G3WDG and I8CVS's S-Band signals received on K-Band.

http://www.g3wdg.free-online.co.uk/s_ktest.htm

73

Charlie G3WDG
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Best 73" de

i8CVS Domenico





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