A weblog focused on interesting circuits, ideas, schematics and other information about microelectronics and microcontrollers.
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Because I have not tested all electronic circuits mentioned on this pages, I cannot attest to their accuracy; therefore, I do not provide a warranty of any kind and cannot be held responsible in any manner.
Laser effect for less than 10 US$
A lot of tips and inspiration for everyone who wants to make cheap (but nice) laser effects.
"I use 2 very common little loudspeakers (diameter is 80mm). On each one, on the radius of the loudspeaker, I dispose a first little piece of wood (a match ;-) (50 mm long perpendicular to loudspeaker axis), glued on the diameter and glued on the centre of loudspeaker (through another little piece of wood 10 mm long on the loudspeaker axis). Then I glued a little mirror on the 1st piece of wood, near the diameter of loudspeaker. When the loudspeaker vibrate, the first piece of wood rotate and the mirror too."
Link: Lasers for amateurs