re blinking leds in article aa kepler unh edu dmn kepler unh edu there s a seeker born every minute writes where can i buy blinking leds besides radio shack does anyone sell blinking leds with variable flash rate by voltage i guess if so what hertz pulse rate are they adjustable or set to i d like blinking leds that can be set for approx hz hz hz or hz something like that i m interested in what s out there for flash rates i like the idea of leds with flasher circuits already in them i hate soldering ics in general guess i don t have a hell of a lot of patience thanks dana if you want slow led flash rates adjustable by switches or by a digitally controlled switch i suggest looking at a oscillator chip they cost at radio shack much cheaper in quantity at quality places and you will be able to find good info about simple circuits in a oscialltor notebook i think forest mims has one at radio shack you ll have to toy with resistor capacitor values or you can use your head with a little math to get the right frequencies any engineer worth his salt can make a osciallator it s in the book and left up to you to see i hate doing ascii circuit graphics the can accurately go from a few hz to about khz i think about the tape recorder gizmo you could alter a stereo tape deck to use one channel as a data line for flashing led and one as audio line for voice or music this would eliminate a lot of noise the data line is probably most easily done by some kind of pll or bandpass filter using just an op amp the chip is a good pll and not hard to work with however if you nothing about how a pll works i suggest you don t try this op amp information can also be found in the forest mims radio shack info booklets and the popular op amp is a snap to work with setting frequency and bandpass filter values are not so easy so i would suggest the method firstmost i have no idea what this is going into so i am really generalizing as for manufacturing techniques if you re only goofing with it i suggest you breadboard the thing no need to solder wire wrap would be the next more permanent step and lastly soldering pcb making hope that clears things squish endor harvard edu
