This 555-based circuit was obtained from the 1995 Encyclopedia of Electronic Circuits volume 5. It triggers an SCR when the transistor is cut off.
This circuit with JFET and Unijunction was found in an ancient American documentation. The...
This metering bridge circuit uses one power supply only. The operational ones depend on the...
We found this configuration in the 1964 RCA transistors manual. As indicator loads in each stage,...