Wire-type acoustic delay lines for digital storage

The paper describes the design of acoustic delay lines using wire as the transmission medium. Delays of 3 millisec or more are possible with resolution adequate to permit a pulse repetition rate of 500 kc/s. The acoustic signal is propagated in the torsional mode in wire of a material chosen for its low loss and negligible delay/temperature coefficient. The torsional mode is used, since thereby a longer delay can be made without intolerable distortion.