I had a Garmin 95 XL that lost signal every time the VOR was tuned to
108.8. Finally figured out that it was the associated DME channel. ie,
when my DME transmitted, a harmonic wiped out GPS reception.

Another wierd one: Apollo (ii Morrow) UPSAT GarminAT (they keep changing
names) GX-60, IFR installation. Whenever I started up on the north ramp at
SFB (Orlando-Sanford), the GPS would not initialize. I had to wait until
airborn, turn it off and back on again, and no problem. Starting up
anywhere else on that airport, or at any other airport, no problem. The
dealer at the north ramp of SFB could never figure the problem. I finally
cured the problem when I stopped using that FBO (for other reasons).

"" wrote in :

Flew my 172M today and experienced some truly bizarre GPS behavior.

On preflight my portable GPS (Garmin 296), with external antenna and
aircraft power securely attached, initialized just fine, acquired
several satellites and went right into NAV mode. After runup and right
before takeoff, it showed total loss of satellite signals and even
after cycling power several times, would not pick them up again.