Instrument for measuring the phase jitter of analog signals

Abstract From the Canadian patent

An instrument measures directly the phase jitter of analog signals transmitted on a line by a device under test, even when clock information is not available and when operating circumstances do not permit the use of analog instruments. It uses a circuit which generates a square-wave clock signal with the same phase and frequency characteristics as the signal to be measured so that a, phase comparison with a reference signal can be made. The error signal so obtained is filtered, measured and displayed.