This circuit for incandescent lamps was found in a 70s documentation. The circuit uses an SCR according to the power of the controlled lamps. The delay is a few seconds, given by capacitor C1.
The circuit is from the 1994 National Semiconductor Linear Applications Handbook. The component used is...
This circuit, which is present in other points of this website, was found in a 90s Hands On...
This simple circuit produces a tone when triggered by any vibration picked up by the sensor. The...