Audio Memo Alert Circuit

Posted on May 31, 2012

This device prevents paper notes and memos from being overlooked. A paper note placed between two fingers made of a conducting material (metal or conductive plastic) breaks the circuit, allowing pair 1 of Ul-a to go high.

Audio Memo Alert Circuit
Click here to download the full size of the above Circuit.

This causes Ul-c Ul-d to act as an oscillator, pulsing piezo buzzer BZ1.

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