This circuit activates a buzzer when the voltage applied to the input falls below a preset value in R1. The circuit is from an 80's American documentation.
August 2016 - It can be purchased from Mouser Electronics new chips from Dialog Semiconductor, the...
With this circuit it is possible to fire an SCR from the light that falls on a phototransistor. The circuit...
Interval pulses emitted by this circuit are picked up in a medium wave radio nearby. The circuit is...