This circuit that we found in a 1990 documentation uses an LED as a sensor. The operational amplifier is equivalent to the 741 and the trigger adjustment is made in the potentiometer.
The flashing LEDs in this circuit simulate a working alarm and can serve as a deterrent to a...
This oscillator or clock generator generates rectangular signals and frequencies up to 100 kHz....
The critical component of this project from a 1988 publication is the transformer. The final power...