wrote in message
ups.com...
Does anyone have experience with mounting two "mouse" GPS antennas in
close proximity of each other? Any interference issues? Specifically,
I'm thinking along the lines of two Garmin 35s, or a Garmin 35 and a
remote antenna for a Colibri, both within a few inches of each other
under an instrument panel cover.


I've had problems with two GPS receivers near each other. My problem was
with a Garmin 12XL which wouldn't work on the dash of a specific car. I
eventually realised that the car was fitted with it's own GPS receiver under
the dash.

Obviously if they are passive there shouldn't be a problem, but I see
the term "active antenna" used and I'm wondering...


It's not just active antennas that will influence each other. I don't know
much about the technical stuff so can't offer a proper explanation, but
you've only got to look at a yagi type antenna (for example a TV antenna) to
see that mounting antenna near each other has an impact. Basically each
element in the antenna is an antenna in it's own right which receives and
re-radiates the signal. In a Yagi the purpose is to increase the
directional gain, but unintentional coupling of antennas is likely to have a
detrimental effect.

Stephen