| 摘要 |
PURPOSE:To prevent the malfunction due to the external noise or the like for the receiver by providing the carrier squelch circuit to the receiver of the repeater station for the terminal station. CONSTITUTION:The electric wave transmitted from terminal station 3 is received at the receiver of terminal station-use radio unit 1 of the repeater station. And the closed aural circuit is opened via the squelch circuit, and at the same time the start is applied to the transmitter of master station-use radio unit 2. Then the wave is transmitted to ratio unit 4 of the master station. Here the carrier squelch circuit, which detects the carrier of the radio communication frequency for operation, is used for the squelch circuit of the receiver in unit 1 in order to secure the response to only the wave sent from the terminal station. As a result, the malfunction due to the external wave, the city noise and the like can be prevented for the squelch circuit, thus realizing the stable circuit constitution as well as an effective use of the electric wave. |
