Production of accurate one-second time intervals

This paper describes the technique wherewith a highly accurate frequency of 1 cycle per second is obtained for broadcasting from the Bureau’s radio station WWV. Multivibrators are used in obtaining lower frequencies from a radiofrequency standard. Observations are given concerning the nature of short-time instabilities occurring in controlled multivibrators. The measuring technique is described whereby the accuracy between successive time intervals or cycles is checked to better than one part in a million. It is pointed out that the arrangement can be used for supplying extremely short pulses accurately spaced in time. The frequency of 1 CIS is added as a modulation on standard radio frequencies, which are broadcast each Tuesday and Friday.