This circuit was obtained from Dutch documentation from 1964. The components are of the time, but current equivalents such as BC548 to BC108 can be used.
This circuit visually indicates that a high voltage is present in an outlet or other point. The...
This circuit found in a 1988 documentation consists of a timer or sequential timer controller. The...
Using a 4017 as a base, this circuit from a 1990s Popular Electronics generates low-frequency...