Beware LED christmas lights by Phillips – they have an annoying 60Hz flicker!
I decided to do the power saving or environmentally conscious thing and buy LED christmas lights to decorate the apartment this year. We picked up a 60 “bulb” set by Phillips for $12 and once they were up it was immediately noticeable that they flicker at a rate just low enough to be perceptible. It should be obvious to anyone that has taken the most basic of electrical engineering courses that AC current flows in two directions, and diodes only let current flow one way, so the LEDs will be dark half the time. Any useable LED set needs to have a rectifier to power the LEDs with DC current instead so they light up steadily.
I saw a review of them here (after the fact of course) and it indicates the flicker might have been fixed in this year’s model, but I can confirm its not.
So if you’re in the market for LED lights, look for some higher quality lights that give off steady light – the things last practically forever so it’s probably worth the investment.