... intelligent voice messenger in case of some problem.Data collection controller can be connected with receiver mainframe via Bluetooth or cable ... data: 1 Hz, 2 Hz, 5 Hz, 10 Hz, 20 Hz (default 10Hz) Differential data format: CMR, CMR+, RTCM2.1, 2.2, 2.2, 3.0, 3 ... temperature: -45~+65 Storage temperature: -55~+85 a lasted advanced multi-channel, multi-frequency RTK GPS system