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Pirate problem on FM satellites, minor problem





The pirate stations randomly heard on FM and SSB satellites
are usually just people operating simplex FM mobile radios
in the satellite uplink part of the band.
These stations are a combination of legimate licensed
radio operators and some illegal operators and taxi operations.
The legal operators are just not following the suggested
gentleman's agreements and in those cases when they discover
their error they will usually comply.
The illegal stations are only a minor problem for satellites for the
following reasons.

1.  Satellite uplink usually requires a significant uplink ERP for 
proper operations (FM and SSB).  The Illegal stations or pirates
are usually a mobile FM transceiver, running 50 watts or less into
a mobile antenna with a gain of 0 dbd or less (typical ERP 25-20
watts).  
A satellite station with a directional antenna will easily over power
the weak pirate mobile signals on most occasions.

2.  Orbit path:
The orbit path, foot print and speed of the satellite will usually take
the satellite quickly
into and out of the pirate area quickly.  If u do hear a pirate station,
his
mobile radio will quickly fade in a minute or two.  If you have a AZ/EL
gain
antenna system, again your signal should usually over power the random
pirate stations.

How can you compensate for pirate QRM.
Simple, install the biggest az/el antennas system you can afford.
And have plenty of reserve capacity for the satellites you plan on
using.
As always, only use the minimum power required for the desired
communications
and follow the suggested ERP uplink ratings for that specific satellite.

Miles
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