... for driver. It can provide the function of voice and data transfer on both GSM-R and 450MHz ... the Control unit,GPS unit,Record unit,GSM-R voice unit,GSM-R data unit,450MHz function unit, ... 3)Control 450MHz function unit to get the relevant voice and data communication operation of known analog order.(4 ... provide driver operation like dial etc.(3)Word and Voice cue of working state.1.2.3 HandsetHandset ...