Accession Number : AD0879588

Title :   A Low-Noise Hydrophone Preamplifier for Experiments with Explosive Sound Sources.

Descriptive Note : Technical memo.,

Corporate Author : SACLANT ASW RESEARCH CENTRE LA SPEZIA (ITALY)

Personal Author(s) : Figoli, Alberto ; Pazzini, Mario

Report Date : 15 NOV 1970

Pagination or Media Count : 33

Abstract : The hydrophone-preamplifier described has a frequency band from a few hertz to above 50 kHz, a voltage gain of 6 dB, and a maximum input voltage for linear operation of 10 V peak-to-peak; it is therefore particularly suitable for experiments with explosive sound sources. Its very low equivalent input noise permits the acquisition of signals only just above zero-sea-state noise level, its input dynamic range of better than 130 dB allows its use with a digital recording system, and its 100 megohm input impedance makes it suitable for low frequency signals even when using low-capacitance hydrophones. An output transformer has been used to minimize crosstalk transmission of the output signal in a multipair cable and an internal voltage regulator provides optimum decoupling when various units are supplied by the same power line from the research ship. The use of highly reliable components has been combined with a rugged construction. (Author)

Descriptors :   *HYDROPHONES), (*PREAMPLIFIERS, UNDERWATER SOUND GENERATORS, UNDERWATER EXPLOSIONS, EXTREMELY LOW FREQUENCY, VERY LOW FREQUENCY, GAIN, FIELD EFFECT TRANSISTORS, PRINTED CIRCUITS, DIGITAL RECORDING SYSTEMS, DATA TRANSMISSION SYSTEMS, INTERFERENCE, RELIABILITY(ELECTRONICS), ELECTRIC CABLES.

Subject Categories : Electrical and Electronic Equipment
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE