| 摘要 |
PURPOSE:To eliminate a signal detector at an input side which had been needed conventionally by providing a hysteresis characteristic to a switching point frequency of the control mode. CONSTITUTION:A transmission signal from an input erminal is iputted to a variable resonance circuit 21; a branch output of the variable resonance circuit 21 is applied to band pass filters FFl, FFo, FFh and detectors DFl, DFo, DFh to detect a residual amplitude deviation after qualization, and its detecting output is inputted to a control circuit 22 having a hysteresis characteristic. Then, a control voltage Vf of a resonance frequency and a control voltage VQ controlling a sharpness obtained at the control circuit 22 are applied to a variable resonance circuit 21. Thus, a characteristic 1/A(omega) inverse to the amplitude characteristic A(omega) of fading is formed and a signal having a substantial flat amplitude characteristic is regenerated at an output of the variable resonance circuit 21. |
