MK 133 buzzer

Hi There,

I know that’s it’s possible to connect a buzzer to the MK133 either next to T6 near the quizmaster SW5 (buzz all) or to each SW1, SW2, SW3 or SW4(buzz first only) but is it possible to get the buzzer just to buzz for a few seconds only and still have the LED on after the buzzer has stopped.

That would require a buzzer and a turn-off timer, which would make the circuit rather complicated. A buzzer with a large electrolytic cap in series might do the job. Please experiment with values. Not sure it will work, this is just a hint. Make sure to provide a discharge resistor for the cap.


I connect a buzzer to the external reset indicator connections - it buzzes, but you have to switch it off manually using the reset button

The connectors are on the bottom edge of the circuit board below the Reset LED