Testing Repeaters with Circulated Pulses

An extension of square-wave and pulse-testing techniques is described which permits the signal pulse to be observed after circulating many times through the transmission system under test. This method is particularly useful for measuring the cumulative effect of a number of similar units, such as those used in carrier or microwave-radio-repeater systems, when only one unit is available. Applications to video-frequency, intermediate-frequency, and radio-frequency testing with a.m. or f.m. signals are discussed.