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Old April 30th 08, 08:13 PM posted to uk.transport.london
Clive D. W. Feather Clive D. W. Feather is offline
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First recorded activity at LondonBanter: Jul 2003
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Default How GPS works (was Bus Information Signs)

In article , Tom
Anderson writes
(* not sure if it goes up to 36, and not sure what the channels
correspond to exactly)


It'll be the number of the satellite. There are 31 at the moment, and
could be more - i don't know if 36 is a design limit.


I believe the "xor two outputs to shift the sequence" system has 36
possible shifts, of which 31 are used for satellites and the others for
special purposes.

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