On Thu, 4 Oct 2007 19:06:46 -0400, "Blueskies"
wrote:


"karl gruber" wrote in message ...
Exactly.

All those radios were designed long before GPS. They are noisy and will interfere with GPS.

That's the reason King made the "A" series of the 155 and 165. They are designed to co-exist with GPS.


Karl

Garmin designed the 396 stuff for airplanes. Those radios are in airplanes. Garmin made the wrong design choices when
making those boxes. Didn't Garmin buy Apollo? You would think they would have some lessons learned in there somewhere...


Maybe if you buy all the equipment from the same manufacturer it would
work. When you mix manufacturers they build things slightly
differently using different fequencies.

It may be a poor analogy but if you bought a door for your car would
you expect it to fit all other cars? :-)

The best cure is an external antenna which is therefore shielded from
the avionics equipment so less vulnerable to interference.

I once came across a problem with a commercial TV transmitter breaking
through into a taxi radio some 40 miles away. The TV transmitter was
well in specification and the spurious were very very low but the taxi
radio has a very sensitive receiver. The taxi firm had to use another
frequency but that's how electronics works!