Light Art

Nervous LEDman
A small analog, interactive light object that responds to sounds and vibrations by flashing a LED. It's very sensitive, and reacts on human voice over a distance of 3m or more, when put on the right surface, e.g. a wooden table, box or anything that vibrates. 
 Nervous LEDMAN consists of 3 parts : ( top down ) 
 1)  battery holder & power switch I use a LilyPad coin battery holder or compatible and a rechargable LIR2032 battery 
 2) LEDMAN PCB It's a redesign of a circuit by Yair Reshef . The original design uses an obsolete opamp and needs 2 batteries for 6V supply.  Now it runs with a single cell and uses a cheap CMOS opamp *) + 3 resistors + 1 ceramic capacitor in "beginner friendly" sized SMD packages (1206) *) many SOT23-5 CMOS opamps, output @ pin 4, tested 
 3) piezo disc sensor this is a common 35mm diameter Piezo sounder/buzzer/speaker/drum sensor. Smaller discs are not recommended until you put LEDMAN straight on a loudspeaker box ;-) 
 the picture shows the "elektro kitsch" (C) version with vintage power resistors as legs and arms. A flexible 38mm, 3V LED filament is used as LED. 
 construction notes : resistor "arms" can be 0...10 Ohm, any wattage. resistor "legs" can be 0...100 Ohm, any wattage. LilyPad connection is a bit tricky : the red "+" wire is soldered straight to a LilyPad "+" pin. The black "-" wire tunnels the other LilyPad "+" pin without connection ( it must be isolated) and is soldered to LilyPad "-" pin on the rear side. The reason is: if you solder a wire to one of LilyPads "-" pins on the battery side, the battery can't be removed anymore ! 
 documentation  :  
 NervousLEDman Schematics (PDF) 
 NervousLEDman PCB Layout ( PDF, 24pcs. 100x160mm single sided) 
 NervousLEDman SMD assembly (PDF) 
 credits go to my friend Yair Reshef and unknown early developers for inspiration and Leah Buechley for LilyPad respect CC NC BY SA