Echo-sounder automatic pulse amplitude compensator - has multivibrator coupled to analog memory addressed by sequential accessing using differential amplifier

摘要

The automatic pulse amplitude compensation for the reflected pulses received by an echo-sounder or ultrasonic transducer. The circuit hunts for an optimum compensation as a function of reflection time and holds it automatically. Compensation is based on the use of a multivibrator fed both by the reflected signal and an error correction signal derived from an analogue memory addressed by sequential accessing using a differential amplifier. Correction is derived from the reflected signal via a detector and an analogue gate. The memory includes a twin input summing circuit receiving the signal to be stored and that from an analogue phase shift register.