| 摘要 |
PURPOSE:To give versatility to the receiver, by using the counting value of the frequency to set the receiving frequency of the voice outband signal. CONSTITUTION:The voice signal of signals demodulated by receiver 1 passes through low-pass filter 2 and is sent to contact (d) of relay 6. Meanwhile, the voice out-of-band signal which passed through high-pass filter 7 has the waveform shaped by counter circuit 8 and has the frequency counted and is compared with the numeric signal from receiving signal frequency setting circuit 10, where the receiving frequency is set preliminarily, by coincidence detecting circuit 9; and if it enters into a fixed range, relay 6 is operated to connect the voice line by contact (d). When the receiving frequency signal is changed, the preset dial of receiving signal frequency setting circuit 10 is set to a prescribed frequency. |
