Found in a 1964 Electronic Design, this circuit makes use of FETs of the time. These transistors can be replaced by modern general-purpose types. The input resistance is 30 M.
This is the receiver circuit for the previous transmitter (CB19628E). The receiver is an infrared...
This circuit was found in old American documentation. Transistor is general purpose and coil rated...
Found in English documentation, this touch sensitive switch must be powered by an isolation...