We found this circuit in a 1968 Electronics World. It fires a buzzer if the ignition key is turned on and the headlight is off. The circuit uses an included oscillator buzzer like the Sonalert.
The BFO or Beat Frequency Oscillator is used to receive telegraphic signals or even modulated in...
Taking advantage of the comparator setting, we can use the Norton amplifier as an over temperature...
This circuit was found in an American documentation from 1975. The components of the time can no...