| 摘要 |
PURPOSE:To provide a degree of freedom to a tone frequency, by using a transversal filter as a filter for tone squelch. CONSTITUTION:An output from a detection circuit 5 is connected to the transversal filter 21 whose characteristics are varied with a switch 22. When the transversal filter 21 is used to improve the S/N, the unnecessary band is cut off by using Formant characteristics by selecting a contact (a) of a switch 23, for example, a reception signal corresponds to a person's voice. On the other hand, the transversal filter 21 is used for tone squelch, the tone of a station itself only passes through the transversal filter 21, by selecting a contact (b) of the switch 23, a switch circuit 6 is turned on and a detected output is applied to an amplifier 7. |
