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Dave Platt Dave Platt is offline
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Default Magellan SporTrak GPS loosing sensitivity?

This is the second time this has happened with a Magellan
GPS. The acqisition time when its first powered up gets longer,
eventually to the point that its unusable. For this model it should be
2 minutes. Yesterday, it was 18 minutes, and that was in an
open area with a clear view from horizon to horizon. I'm
guessing its because the receiver is loosing sensitivity for
some reason.

Has anyome else delt with this and found a solution?
I'd rather try to fix it myself rather than sending it to Magellan.


GPS receiver lock time is not predictable. Run more tests before you send
it back. No, you probably can't fix it yourself.


One possible cause for the problem would be RF interference. The GPS
signal itself is quite weak, and any (deliberate or spurious)
transmissions near the GPS frequency could interfere with the
receiver's ability to pick the signal out of the noise and lock onto it.

Consider the following case:

http://www.gpsworld.com/gpsworld/art...l.jsp?id=43404

A malfunctioning TV-antenna preamplifier, powered up but stored inside
a paint locker onboard a small boat (!), was radiating enough noise to
knock out GPS reception throughout all of Moss Landing harbor and for
a distance of at least 1 km out to sea!

I agree that further testing of the "insensitive" Magellan GPS is
called for, before it's sent back for repair. The problem may lie in
the local RF environment, rather than in the Magellan itself... if so,
the problem would probably affect GPS receivers of other makes and
models in a somewhat similar way.

--
Dave Platt AE6EO
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