Circuit arrangement for measuring the phase modulation disturbance of a test signal

摘要

A circuit arrangement for measuring the phase modulation disturbance of a test signal which is passed through a test object and wherein a heterodyne oscillator supplies an input to a mixer which receives the input signal and supplies an output to a detector and display device and wherein the output of the mixer is applied to an automatic frequency control loop including a reference oscillator phase discriminator and a low pass filter which supplies an input to the frequency control input of the heterodyne oscillator.