Calibration circuit for expendable sonobuoys

Abstract

Calibration of expendable sonobuoys can be made in-situ to assure the transmission of representative data. A pair of integrated circuit timers are coupled together to provide on-off duty cycles during which a spectral distribution of calibration signals is fed to the sonobuoy. Since the spectral distribution and amplitude of the calibration signals are known, a remote monitoring station is continuously apprised of the sonobuoy's calibration.