GROUP DELAY TIME CORRECTING CIRCUIT INCLUDING A TOULON CIRCUIT FOR USE IN AN INTERMEDIATE-FREQUENCY AMPLIFYING CIRCUIT

摘要

A group delay time correcting circuit including a toulon circuit for use in an intermediate-frequency amplifying circuit. The intermediate-frequency amplifying circuit is comprised of an amplitude limiter, a group delay time correcting circuit and a detector circuit coupled to the output of the group delay time correcting circuit. The group delay time correcting circuit includes a differential amplifier for converting the input signals thereto from the amplitude limiter into two signals equal in amplitude but opposite in phase. The output of the differential amplifier is applied to a Toulon circuit comprised of a series connected reactance circuit and a resistor. The output of the Toulon circuit is taken at the junction between the reactance circuit and the resistor. The reactance circuit of the Toulon circuit is constructed so as to have at least one resonance point and one anti-resonance point.