[amsat-bb] Redundant geostaionary birds?

[Andythomas]

Hi gang,

I was reading an ESA press release about satellite radio experiments and
didn't realise its emphasis on re-using redundant broadcast tv satellites
until I read the bbc version of the story at:

http://news.bbc.co.uk/1/hi/technology/6301359.stm

which explains that when the broadcast geostationary saetllites lose fuel
for position control the tv guys lose interest in them, even though the
transponders work fine.

Then I fell to wondering:

 whether we in the amateur satellite service could not use both the up and
down links on these redundant geostationary birds?

I don't know the exaxct frequencies but there may be one out there that has
frequencies we share (or at least the uplink). After all we have years of
experience of chasing staellites which are not exactly where they should be
in the sky and so the "wandering geostationary" satellite shouldn't be a
worry.

I think each transponder channel is 27 MHz wide??

I remember vaguely that there was a "pipe" on one of the birds from the UK
to the USA which was used in amateur service about 15 years ago now (but I
don' t remember very much else).

If we could take over one channel on the transponder then immediately we
would start looking at uplink equations, multiplex etc. and what about a
mobile aprs service?!

90% of the world will tell you why it can't be done. Who can show how it
can be done?

73 de andy G0SFJ