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Sound-Controlled Relay

April 21, 2011 Rend 0

This is a relay circuit that detect the presence of sound to activate the relay. You can use this sound-controlled relay as voice operated switch, […]

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Door Intercom

November 25, 2010 Rust 0

Door intercom is very useful for home security. If you receive a door knock or door bell/alarm, you can push this intercom knob and ask […]