... signals, the Trimble R6 can be upgraded with additional GLONASS support for scalability. With integrated communication choices, flexible data collector solutions, ... 232 serial on Port 2 (Dsub 9 pin)• Fully integrated, fully sealed internal 450 MHz receiver/transmitter option:− ... typical /10 km optimal• Fully integrated, fully sealed internal GSM/GPRS option• Fully integrated, fully sealed 2.4 GHz ...