PURPOSE: To vary the state of a receiver at any time by allowing a transmission equipment to send an instruction code representing to which state a receiver is to be transited succeedingly with respect to a code sent form the receiver and representing its own state.

CONSTITUTION: When a customer visits to a reception window, the operator uses an input section 14 to inform it to a control section 11 that there is a visit from the customer, and a receiver 2 generates a call code for registration and a registration information revision instruction code. A transmission equipment 1 discriminates a state code sent from the receiver 2 and sends the call code and registration information revision instruction code B generates as above to the receive 2 in the initial state. Then the transmitter 1 sends a radio communication start instruction code to bring the state of the receiver 2 into the radio reception mode. The operator delivers the receiver 2 whose registration is finished to the customer. Thus, the receiver is called easily for plural number of times and the efficient operation of the information managed by the transmission equipment is attained.