This circuit makes use of a low impedance microphone. The relay is according to the supply voltage which can be between 9 and 15 V. The operational gain is approximately 100.
This circuit can be used in alarms, data links or áudio links using IR radiation. The circuit is...
The figure shows the basic configurations for unijunction oscillators. They are relaxation...
This circuit switches on an external load after a certain interval given by the capacitor. The...