At 11:01 PM 11/15/2009, Vitaliy wrote: >A question for the battery experts. What type of batteries is commonly used >in "battery-less" flashlights and fast-charging toys? I have an early version of one of those - it looks very similar to the ones that Active Tech (Canadian chain store) were selling last year or the year before. Mine is legit - no coin cells hidden inside. A coil with MANY turns of wire, a large nickel-plated magnet, a 4-diode bridge rectifier feeding a small 3-cell shrink-wrapped NiCd battery pack, a current-limit resistor that feeds the power switch, then to the LED. I'm assuming the battery is NiCd just because of its age - this was a gift to me before NiMh became popular. I see three ridges under the heat-shrink tubing. I've often thought of winding 2 more coils on the former and adding two more bridge rectifiers - there certainly is enough space on the coil former. The existing coil occupies almost exactly the middle third of the former, leaving both ends completely open. The interesting thing is the monster (plastic) lens in front of the LED - it makes the 5mm LED appear to be much larger than it really is. Mine works for many minutes after shaking for a while (while is defined as some 10's of seconds or a tiny number of minutes, not sure). Its not real bright, though. dwayne -- Dwayne Reid Trinity Electronics Systems Ltd Edmonton, AB, CANADA (780) 489-3199 voice (780) 487-6397 fax www.trinity-electronics.com Custom Electronics Design and Manufacturing -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist