I'm picking up a Vaisala RS-80 15G radiosonde.  This sonde has a GPS receiver board and communicates with the other boards on the device on a serial line, 1200 baud FSK.

I've been looking for information on what signal this GPS board puts out--does anyone know if is it a NMEA standard signal sentence?

I have other uses for the telemetry and 403mhz transmitter on-board, but I'm thinking of incorporating the GPS receiver into an APRS transmitter.

Next step, I wouldn't mind picking up the add-on radioactivity sensor board, if I can find one for sale.  

Anyway, main point was:  has anyone else played with one of these before, and does anyone know whether the serial output from the GPS board is NMEA standard?  If it is not, do you know what the format is?

Jim