Abstract: An apparatus stores a plurality of mobile identification numbers. When a user selects at least one of the stored mobile identification number and the apparatus receives a mobile identification number transmitted from a base unit, the received mobile identification number is compared to each selected mobile identification number. When the user does not select any of the stored mobile identification numbers and the apparatus receives a mobile identification number transmitted from the base unit, the received mobile identification number is compared to each of the stored mobile identification numbers. When the received mobile identification number coincides with one of the selected mobile identification number or one of the stored mobile identification numbers, the apparatus is enabled to communicate with the base unit.

Abstract: A portable radio transceiver wherein an isolator which impedance varies usually with the frequency of a communication signal is connected to a power amplifier for power amplification of the communication signal as its load so that, when the frequency of the communication signal is changed through selection of the communication channel, the load impedance of the power amplifier is also changed and correspondingly the consumption current of the power amplifier is changed. In the portable radio transceiver, in order to suppress the change of the consumption current of the power amplifier, an impedance compensation circuit which impedance varies in its direction opposed to the isolator depending on the frequency of the communication signal is separately connected to the power amplifier, whereby changes in the impedance of the load side when viewed from the power amplifier can be substantially cancelled each other.