I believe this radar is the same as on my boat - CRT display??
If so, from what I can remember, you can only feed a Loran signal into it to show on the display. I say Loran, but I have mine fed with an older NMEA version from my AP-Philips Mk6 GPS. The NMEA from the Navman plotter would not display.
From memory (my boat is 30 miles away), I don't think there is any output from this radar.
(I could always be wrong!!