Despite being transistorized, this is a constant current source circuit for 1 V valve filaments such as the 1H4 tube.
The circuit shown here is a CCO. The frequency here depends on the current through the...
This module includes an optical pass key and has two digits. We found this circuit in a 1995...
This circuit can source up to 1,000 V from a 9 V battery. Output current is very low, some...