Time-Amplitude-Frequency (T-A-F) - A special electronic unit for measuring the TVG function of research echo sounders

摘要

High precision in hydroacoustic instruments for fisheries research demands high precision andreliability in the test instruments. To simplify the test measurements, a special test unit has beendeveloped. The operating principles are described, and a technical description is given for thisspecial-purpose signal generator. Application of the unit is described in detail, and an easy way toverify the accuracy of signal amplitude and frequency is recommended. Finally a computationalexample to derive correction factors is given.