We found this circuit in an old American documentation, but the circuit can still be assembled with ease as the used components are still available. MOSFETs admit equivalents.
The 556 consists of a double integrated circuit 555, which can be replaced by them in this...
We found this circuit in a Radio Electronics from January 1967. The SCR is already the C106, which...
This circuit is from American documentation from 1970. It can be designed with a BC558 and for the...