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 found in Radio Electronics magazine from October 1966. It consists of a rhythmic...
This circuit is from a Popular Electronics from the 90's. The circuit provides an output for a...
The transformer of this unit found in an old Japanese documentation can have 22 to 25 V of...