This circuit was found in 1980s American documentation. The transducer is a piezoelectric capsule and the power supply voltage can be between 3 and 18 V.
In the figure we have a practical circuit for a 50 kHz bandwidth amplifier using a photo diode as...
This circuit consists of a small inverter that can generate a few hundred volts of DC voltage...
Found in a 1967 Electronic Design, this transistorized circuit compresses and then expands a pulse....