I just opened a GPS antenna to shorten the cable. Why they're sold with
a 10 meter (!) cable is beyond me, however, after peeling off the
sticker on the bottom, you'll see two magnets held in place with
screws. Simply remove the screws and remove the magnets.

BTW, my GPS antenna cable is now less than 12 inches long, has no
magnets, and works just fine.

On 4/5/2017 12:35 PM, wrote:
Thanks for pointing out these lower-cost antennas. I see the Amazon antenna has a magnet in the base: that would make it unacceptable to me, since it will be near my compass, unless the magnet can be removed.

I've never been able to understand the FAA regulations about TSO components. But have been told by several mechanics that its legal to use non-TSO components in an experimental glider. An adsb installation will need to be certified before use, and every two years, and you can also request an inflight test from ATC.

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Dan, 5J