Nigel wrote:

I have a Silva S15 radio and a Garmin 152 GPS. I don't seem to be able to
connect the two. The Silva manual shows that I need to connect Red (GPS+)
and Green (GPS ground) to the Garmin.


The Garmin has the following
Red (10-40vdc)
Black (ground, power and data)
Blue (NMEA out , COM 1 TX)
Brown (NMEA in, COM 1 RX)
White (NMEA in, COM 2 RX)
Green ( no connection) ????? what's does this do then
Yellow (Alarm Low)

I guess I need to connect the green Silva wire to the Black Garmin, but
what about the red Silva wire, should that go to the Garmin red (10-40vdc)
or the blue NMEA out?.

From your description it is clear that you should connect
green to black and red to blue. The next problem is to make sure
they're using the same baud rate and same NMEA dialect.

Any tips on physically connecting these tiny little wires ?

Just strip off a quarter or half an inch of insulation (if not done
already) and temporarily hold them together with a clothes peg or
paper clip (but keep them apart from each other). This temporary
method will at least let you quickly determine whether they do in
fact work together.

Then either solder them together and cover them up with insulating
tape or use those little screw terminal blocks.