[aszy]

New to the marine electronic environment. In the nav station, I have an NMEA cable coming into the back of our Standard Horizon VHF unit, supplying it with the GPS info. How easy is it to "T" that connection so that I can supply the MacBook with the GPS info via the USB port? I understand that I will need a device to bridge from the NMEA cable and language to the USB port, but I don't know what works well.
Al Szymanski

[ebgb]

you might find it easier to go via usb to the mac book first, then, another usb adapter to put the nmea back out to the dsc

rs232 to USB adapters are cheap as chips, £3 on ebay, look for one that uses the PL2303 chipset - the drivers work perfectly under OS X

got something similar here, macbook pro. Garmin GPS data come into GPSNavX via one usb adapter, then repeats itself back out via another one to the DSC

[georgelewisray]

The GPS is 'talking' on two conductors, (a) grd, (b) data out.

The VHF and the 'serial to USB' are both listeners. One 'talker' can can supply numerous 'listeners'. One potential issue is ground loops but if all the units are supplied power by the same 12VDC system on your boat (or are self powered/battery) then it is a non-problem 99.99% of the time. just twist the wires together and go. the trick is to have the manuals with the connector pinouts for the devices involved.

(1) Data grd for all three devices twisted together.
(2) GPS data out twisted to the 'data In' of both the VHF and the Serial to USB DB-9 plug.


Note: The exact names of the pins/wires/conductors may vary.

[GPSNavX]

For those who need a bare wire to DB-9 connecter we offer such a cable..

http://www.gpsnavx.com/html/datacable.html

[Jade]

I would recommend using a terminal strip and properly terminating each wire with a connector. Since not all devices use a common ground for DC power and signal, it is important to connect the signal grounds together.

If you want to transfer waypoints to your GPS, also connect the Mac USB/Serial cable output wire to the GPS NEMA input.