To receive and display information transmitted to a user from a maintenance operator at a host station by separately obtaining the test results of outgoing and incoming lines.

A transmitter-receiver 1 for test receives already known picture data from a radio base station through an outgoing speech channel. A control circuit 8 compares the received picture data with the same already known picture data held in advance in the circuit 8, calculates the occurring frequency of errors in the outgoing speech channel from the bit number difference between both data, and transmits the calculated results to the radio base station. Then the transmitter-receiver 1 transmits the already known picture data held in the circuit 8 to the radio base station through an incoming communication channel. On the radio base station side, the occurring frequency of errors in the incoming communication channel is calculated in the same way from the received picture data. The transmitter-receiver 1, in addition, receives picture data and speech data outputted from the radio base station and outputs the data to the outside through a display element 12 and loudspeaker 10.