This sample and hold circuit is from a 1969’s documentation. However, it can be built with modern equivalent components, including the matched pair of transistors.
This oscillator circuit for sinusoidal audio signals with operational 741 requires a symmetrical power...
Found in a 1974 Radio Shack documentation. This circuit must have a connection to the ground of...
This sensitive circuit detects the live pole of a power grid or outlet. The circuit makes use of a high...