... :Minimum signal tracked: Minimum signal tracked: -159dBm10.Serial Port: 1).Two full duplex serial communication, TTL interface, with user selectable baud rate ... output (GGA, GSA, GSV, RMC (VTG ,GLL and ZDA for optional)) 3).SiRF binary:position, velocity, altitude, status output 11 ... and Production ofthe GPS Antennas , GPS Modules and GPS Receivers for ten years. We have strong R & D capability, and ...