"Roger Long" wrote in
:

Looking at the PDF version (thanks for the link), I see that the radio
calls both wires "NMEA IN", one is + and the other - so connecting to
ground makes sense. But, why wouldn't they just do that inside the
radio and have you just connect one wire?



Well, yes and no. Connecting NMEA - to ground is because the cheapassed
NMEA manufacturers departed from the balanced, noise-free lines the
original RS-422 specifications had to save a few pennies/unit. Most NMEA
outputs only have one wire and ground....ground is NMEA - as soon as one
listener or the talker grounds NMEA - at only one point....making all that
data noise in the damned RADIOS! Grounding NMEA - doesn't hurt anything as
long as you don't also have NMEA + GROUNDED at any point in the system. In
your post, I thought you were grounding both NMEA - AND + to ground.

Garmin only uses NMEA + for data....damn them. So doesn't Icom...damn
them, too.

Larry
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