| 摘要 |
PURPOSE:To obtain the desired nonlinear emphasis characteristics even with a small input signal by connecting a series circuit consisting of a filter circuit and a nonlinear circuit in parallel to an amplifier and adding a phase inverting circuit to said series circuit or amplifier. CONSTITUTION:When a signal Vi is supplied to an input terminal 1, the signal of (a) shown in the diagram is supplied to the input terminal of an amplifying circuit 3. The signal of (b) is delivered to the output terminal of a phase inverting circuit 4. If the voltage gain of the circuit 3 is defined as (n), the signal V2 is turned into a signal which is (n) times as much as the signal V1 with 180 deg. phase inversion. The signal applied to both terminals of a series circut consisting of diodes D1 and D2 and a capacitor C2 is set at (n+1)V1 as shown by (c). Thus the signals of (n+1) times as much as those of a conventional nonlinear emphasizing circuit are supplied to both terminals of said series circuit. As a result, the amplitude is also (n+1) times as much as the conventional value at both terminals of diodes D1 and D2 respectively. Therefore the signal Vi which is used to obtain the characteristics equivalent to those of a conventional circuit can be reduced down to 1/n+1. |
