In the config.ini I have car_rate set to 9600 and I browsed through the gpsapp source code and see that it opens the serial port at 9600 baud when protocol=earthmate is in the config.ini which I also have set.

I'm not too much of an electronics person, but can I simply apply a 6v voltage from a 3rd source to pin 4 and add another wire to pin 5 for ground? Is that dangerours to the gps receiver or the empeg in any way if i try that?

According to http://www.qsl.net/ka9mva/earthmate.htm it says I can power the unit from pin 9 with 6 volts. Is it safe to try to send 6 volts there? The page doesn't say where I should ground it, should that be grounded to pin 5 as well if I do that? Maybe if the unit is power from pin 9 instead of batteries it won't require the DTR signal.