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RE: Pirate problem on FM satellites

> Continuous Tone Coded Squelch Systems (CTCSS) work well for 
> keeping weak, 
> annoying signals from opening receiver squelch.  CTCSS can't 
> reduce or 
> eliminate the effects of strong, on tune signals.  You either have to 
> overwhelm them to capture the receiver or substantially 
> reduce the unwanted 
> signals in the direction of the satellites.

Which isn't practical, unless we all run our maximum legal power into a long
Yagi pointed at the bird...

> Of course, turning OFF the offending stations is the best way 
> to reduce 
> interference.  How to make this happen involves international 
> relations, 
> finance, diplomacy, and other things far over my head.....

That is the best method.  The next fallback is to use the affected bands as
downlink bands, which will minimise the impact of the problem down to a
local problem, and when there's a strong downlink (e.g. SO-35), annoy the
perpretrators and hopefully make the band a less attractive place to sit in
the long term.

We have a similar problem on 10m with our terrestrial repeaters, and there's
a growing consensus that simplex gateways are preferable to repeaters
because of the high activity they can generate on their Rx/Tx frequency
(unlike a repeater, which has a quiet input), and that activity makes the
gateway frequency less attractive for pirates to sit on.  CTCSS can then be
used to allow the stronger legitimate signals through (in this case, the
amateur signals usually overpower the pirates, unlike the satellite case).
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
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