Continuous discrimination between sudden changes in pulse repetition periods

The paper describes a pulse rate discriminator designed for discriminating pulse repetition periods over a wide range extending from 100 ¿sec. to i m. sec. with pulse width 50 ¿sec. The discriminator gives an output, suitable for operating a pen-recorder or for display on an oscilloscope, only when the pulse repetition period is suddenly changed. The unit can be used in the study of the state of ionized layers of ionosphere.