You need to get the wiring information for your GPS, probably on the
manufacturer's web-site, to identify which pins are for NMEA + and - wires.
If it's not in your GPS instruction book or the web-site, call or email the
manufacturer to get it.
I bought a serial connector to connect to the serial connector of my Garmin
and ran two wires from the + and - pins to my iCom (and my Furuno 1622 radar
display). Make sure you set your GPS interface for NMEA 0183, version 2. I
also set the GPS transmission speed for the slowest BAUD rate: the radar
doesn't display the GPS info if I set the BAUD rate fast.
Page 35 of the iCom 502 Manual
http://www.icomamerica.com/support/manuals/ic-m502.pdf
GPS RECEIVER JACK Connects to an optional GPS receiver to input the position
data and time data.

..A GPS receiver appropriate for the IC-M502 is not supplied from Icom. An
NMEA0183 ver. 2.0 is required for position or time indication, etc. Ask your
dealer about the GPS receiver.

NMEA (+) to center of RCA connector; NMEA (-) to edge of RCA connector



"RvdP" wrote in message
oups.com...

Hello all,

A week ago I bought myself an Icom M502. I already have an external
GPS unit which has a standard serial 9 pins connector.
Does anybody know which serial pins I use to connect to the NMEA in on
the Icom?

Thanks,
Ronald.