This circuit triggers an alarm in the event of a power failure. The circuit is from an 80's documentation, being powered by 9 V battery. The parts are common today.
This circuit was obtained in an Electronic Engineering of the 90s. The operational amplifiers and...
This circuit is from a 1966 General Electric documentation. The circuit applies to sensitive SCRs for...
This unijunction transistor oscillator is intended for Morse code practice. The circuit is from an...