Serial GPS as time source on Windows 7?

Question

How do I use GPS device connected over serial port as a time source in Windows 7?

I have a GPS receiver on my mobile phone which sends data using Bluetooth serial link in NMEA format to computer.

Answer 1

All of the following NMEA sentences contain UTC time

$GPZDA $GPRMC $GPGGA

$GPZDA is best because it is designed to tell the time.

The others can be off +- a couple of seconds.