| 摘要 |
PURPOSE:To inform surely the presence of a call to the operator by providing a group code number set circuit, a group number identification circuit and an alarm circuit and raising an alarm when a preset group code number is identified. CONSTITUTION:When a control channel is received by an antenna 1 and subjected to high frequency amplifier 2, the frequency of the 1st local oscillating circuit 5 os multiplied (4) and mixed with the 1st mixing circuit 3. The 1st intermediate frequency from the mixing circuit 3 is amplified (6), mixed with the oscillating frequency of the 2nd local oscillating circuit 8 at the 2nd mixing circuit 7, the 2nd intermediate frequency is amplified (9), detected (10) and inputted to a group code number identification circuit 11. When the identification circuit 11 detects the group code number coincident with the group code number preset to a group code number set circuit 12, the number drives a buzzer circuit 13, an alarm tone is generated from the speaker 16, an LED display circuit 14 is driven to light an LED17. Thus, the operator knows the call surely. Then the circuit is reset (15) and the operation of the buzzer and the LED is stopped. |
