[amsat-bb] Re: Why do hamsats? (Or anything else...)

John B. Stephensen kd6ozh at comcast.net
Sun Oct 18 15:44:36 PDT 2009

Suitsat 2/ARISSsat is a linear transponder done with DSP. Its seems 
perfectly reasonable to me to do transponder signal filtering and command 
decoding digitally as it makes things smaller and lighter. You could also 
make a better transponder by forming filters around the uplink signals so 
downlink power isn't wasted by repeating noise and downlink power could be 
allocated equally among users.

Putting ARISSsat on the ISS would be nice but NASA and the Russian space 
agency haven't agreed to that.



----- Original Message ----- 
From: "Rocky Jones" <orbitjet at hotmail.com>
To: <k6hx at arrl.net>; "Amsat BB" <amsat-bb at amsat.org>
Sent: Sunday, October 18, 2009 15:32 UTC
Subject: [amsat-bb] Re: Why do hamsats? (Or anything else...)

> That still doesnt answer the question of why on Suitsat 2 they should fly 
> a digital transponder.
> In my view better engineering doctrine would imply that we try and put the 
> digital transponder ON ISS and let it "cook" there for a bit.
> Robert WB5MZO

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