Calibration reflector
Original version
This report is not to be cited without prior reference to the authorAbstract
Calibration of scientific echo sounders and integrators entails,
inter alia, measurement of the dynamic range. This can be done by
repeating on-axis measurements of echoes from each of two different
standard targets. When a large dynamic range is to be tested, use of a
reflector may be convenient. An example is given for which a target
strength of roughly 15 dB was desired for use at 38 kHz. The solution:
a 12-mm-thick copper disk of 50-cm diameter, is described. Results from
its first field applications, where linear operation of a new acoustic
system over a 56-dB range was established, are given.