Sound sensor circuit diagrams
Voice Operated Switch
This circuit is a voice operated switch (VOX) and designed for audio frequencies within a commercial telephone bandwidth of 100Hz to 3000Hz. Input amplitude is sensitive down to 10mV and the output comparator can drive a relay or interface to micro processors and TTL switching between 0 and 5Vdc. Read more...Whistle Responder
Beeps when hears your whistle. A gadget suitable for key-holders, games etc. Read more...Audio Perimeter Monitor
This circuit is intended for audio surveillance of an unattended area, examples being a back garden or open space. It can be used to listen for wildlife or just as an extra pair of ears. Read more...Room Noise Detector
One LED monitors three levels: 50, 70 & 85 dB Useful to detect too noisy environments Read more...Electronic Candle Blow Out
LED or bulb switch off with a puff. Funny gadget - 3V Battery supply. Read more...
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