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Art Todesco
 
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Default LED Xmas lights

Jeff Wisnia wrote:
James Sweet wrote:



It prolly wouldn't take a very big electrolytic capacitor to level
those current pulses out, huh?

Easy to do fer your own strings I guess, but that doesn't help for
all the others you have to look at.

Fortunately that 60 Hz flicker rate is above what triggers
photosensitive epilepsy in most persons sensitive to that.

http://www.epilepsy.org.uk/info/photo.html

Jeff




Don't even need a capacitor, a simple bridge rectifier changes it to
120Hz flicker, pretty much not noticeable unless you scan your eyes
past it quickly.



My thinking wuz that by using just a cap, you wouldn't change the total
energy delivered to the string of LEDs significantly, but with full wave
rectification you'd double it and possibly blow an LED if the original
design had them powered pretty close to their safe limit. Capice?

Jeff

Good thought! But you have to put a
diode somewhere to protect the
electrolytic capacitor from seeing AC.
I guess you could "sacrifice" the
1st LED and put the capacitor after it.
But, there are parallel and/or series
resistors in the sockets, so you have to
be carefull. A separate diode
would probably be best.