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.
The presented circuit uses a symmetrical power source to supply an amplifier with the LM139 or...
This circuit was obtained from the 1995 Encyclopedia of Electronic Circuits Volume 5. The circuit...
The circuit shown is from the 1994 Linear Applications Handbook by National Semiconductor. Some of...