This 40-second delay switch was found in a 1965 Electronic Design. The unijunction transistor might be the 2N2646 and the SCR a sensitive modern equivalent.
Suggested to power the previous circuit, this power supply was found in the December 1990 issue of...
This is a very useful autotransformer circuit on the bench. We found it in the September 1970...
This circuit was obtained in a 1960 documentation of General Electric. It is applied in the...