"Dave" wrote in message
...

Next step is to hook the serial connection up through a terminal block so
I
can also pull off the signal for routing to the DSC function of the VHF,
and
then create a decent mounting to keep it from moving around in a seaway.



Danger Will Robinson! Danger! That terminal block connection may introduce
noise. Don't be surprised if the errors go up.

Check the RS232 levels out of the computer and what the serial input on the
GPS requires. Some of those notebooks are not up to RS232 standards (they
are +/-5V rather than +/- 12V) or even pseudo RS232 single ended 0-5 Volt.

Sometimes the problems can be very intermittent and will drive you crazy in
trying to find them.

Lame-O batteries make the RS232 even worse.