MONLINEAR EMPHASIZING CIRCUIT

摘要

PURPOSE:To make the amount of emphasis of a nonlinear emphasizing circuit symmetrical for a center frequency by adding a capacitor in parallel to one couple of diodes which are connected reversely in parallel to constitute a limiter circuit. CONSTITUTION:A macro signal from an input terminal IN is amplified by a transistor (TR)Q3 and supplied to a circuit T which traps the center frequency and the limiter circuit LM. The limiter circuit LM is provided additionally with the capacitor C4 in parallel to one couple of the diodes which are connected reversely in parallel. Consequently, the operation of the limiter as less deterioration as the frequency is higher. The limiter level is controlled by TRs Q4 and Q5 according to the input level and an output having symmetry for the center frequency is obtained as the output of a TRQ6 constituting a buffer amplifier.