It is probably the processor or clock on the 296.
Physical separation between the two should eliminate the hiss.
Take the 296 and walk around the house with different electronic audio
devices turned on. Hold the 296 in close proximity to each electronic
audio device and listen for the hiss. (CD player, AM/FM stereo,
television, etc.) Make the 296 change screens, scroll a map, etc and
listen to determine if the sound of the hiss changes.

Cub Driver wrote:
My Garmin 296 causes a hiss in the Vertex handheld sufficient to make
the radio unusable when they are mounted close.

Where does the interference come from? If I use the remote antenna on
the Garmin, will that suffice, or do I have to separate the two boxes?
all the best -- Dan Ford
email: (put Cubdriver in subject line)

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