This circuit provides a delay for the activation of an alarm, giving the owner time to leave the premises. The circuit is from the 1995 Encyclopedia of Electronic Circuits Volume 5.
This interesting circuit measures the distortion of the sinusoidal voltage of the power grid. We...
The operational amplifier used in this old application is not common today, but more modern...
Used in 1950s CW receivers, this type of circuit used germanium transistors. The circuit has...