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.

Leave Comment

characters left:

New Circuits



Popular Circuits

Ttl logic tester
Arduino Master Reader
IR remote control signal receiver using AVR microcontroller
gsm gps based vehicle theft control
Keep The Ramp right
1 Hz Pulse Frequency Generator with 555
Pulsing Third Brake Light Circuit
18 dB LT1253 DDS Amplifier
Low phase noise voltage controlled oscillator circuit
XTR105 RCV420 composed of 12V power transmission reception circuit diagram of the ring
One of the battery discharge protection circuit