GPS & XM antennas
Instructor
Joined: Jan 2009
Posts: 155
Likes: 0
From: Mesa AZ
I initially mounted both on top of the HU (under the dash). XM antenna was fine but had intermittent satellite acquisition issues with navigation. Moved the GPS antenna to a windshield mount in front of rear view mirror. No problems since.
Le Mans Master
Joined: Jun 2004
Posts: 9,289
Likes: 16
From: Skippack PA
St Jude Donor '13
With our fibreglass cars, interference aside, it doesn't really matter where you mount the GPS antenna. The XM antenna however is far more sensitive and I think no matter what you do unless you live in an area with a LOT of terrestrial backup signal you're going to get drop-outs. That's due to the fact that XM & Sirius like to use the body of the car as part of the antenna using magnetic coupling and that obviously ain't gonna happen for us.
