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

[John B. Stephensen]

For 13 cm uplinks we can just overpower the interferers. The WiFi
interference is attenuated at the same rate as the uplink signal. Most
interferers are 10 mW EIRP or less and the uplink is 1 KW EIRP or more.

For a 13 cm downlink, increasing the power level is impractical as solar
panels are very expensive.

73,

John
KD6OZH

----- Original Message ----- 
From: "i8cvs" <domenico.i8cvs at tin.it>
To: "Greg D." <ko6th_greg at hotmail.com>; "AMSAT-BB" <amsat-bb at amsat.org>
Sent: Monday, September 11, 2006 02:11 UTC
Subject: [amsat-bb] Re: S band and Eagle: an appeal for a
higherleveldiscussion


> ----- 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
> --------------------------------------------------------------------------
--
>
> Best 73" de
>
> i8CVS Domenico
>
>
>
> _______________________________________________
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