Found in an English documentation, this circuit serves as a receiver for modulated sources of ultrasound. The sensor is a ceramic capsule. Transistors are general purpose types.
This very old circuit, from a publication from the 1970s, uses a germanium transistor and two...
In the figure we have a very sensitive touch switch circuit. A touch of the sensor causes the...
In fact, we can say that this circuit found in documentation from the 90s, consists of an intercom...