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I want to make christmas lights blink! Answered

I want to take a string of LED Christmas lights and add some form of relay that causes the entire light string to blink. I'm sure this can be easily achieved by adding some kind of in-line relay or circuit, but I'm not quite sure what I'm looking for to add. Any ideas?


if the current of the lights is not > 100 mA and there are just leds and resistors (no other electronic components) i'd try fluorescent lamp starter in series with it

(note - starter may sometimes overheat. close it in unflammable metal box)

if anything else - use 555 chip (i took most of the circuit below from the xbox mod)


Either go to a store and buy a "Christmas light blinker," or make an RC circuit (a resistor and capacitor) with the right time constant. Use Google or Wikipedia to learn what "RC circuit" means. Google Is Your Friend.

Oh boy that's SO over my head. I understand the concept, though. A capacitor in-line with a resistor causes the capacitor to charge until the capacitor is full. Every time the capacitor is at a full charge, it either opens or closes the circuit. That about it?

That's the basic idea. There may be simpler ways, though. See the very first link that comes up when you Google your own topic ["christmas lights blink"]. Amusingly, now that you've created this topic, it's the third Google hit :-)

I agree, Kelseymh. I simply didn't know what to google. That's all. Thanks for the RC Circuit bit!