The Series 3800 Vehicle Intercom System is engineered to solve the problem of communicating in high-noise environments with a mobile vehicle platform. Fire apparatus, rescue vehicles, ambulances, command and control vehicles, airline deicers and paint stripers are but a few applications that currently benefit from the Series 3800 system. The U3810 adds the transmit and receive functions of a mobile radio to the Series 3800 Intercom System. Use of this module is recommended for two- or three-person systems only, as all intercom users will transmit over the radio while the PTT is depressed. It is a simple method of adding radio interface capability to systems where users are within close proximity to each other and are capable of sharing the PTT transmit switch.