This 80's circuit turns off a TV or other appliance after a set time. The base is a 555 IC and the relay is according the supply.
This oscillator was found in a 1967 EEE. The transistor supports a modern equivalent. The power...
This second-order low-pass Salen-Key filter was obtained from an American 1980s documentation. Formulas...
This interesting circuit of a 1988 documentation consists of a mouse trap where the sensor is left to...