Reply to post: Re: solution

BOFH: We must... have... beer! Only... cure... for... electromagnetic fields

NickHolland

Re: solution

YES, the AC frequency is 50/60hz.

HOWEVER, fluorescent and most other lights flicker at TWICE that -- the light on both halves of the AC wave form, so you get a 100/120hz flicker. Usually not a problem, though noticeable if motion is involved.

LEDs have a very fast response rate, but 50hz is so low, even an incandescent light can have measurable flicker. What's different for LEDs is they are respond to only one direction of current -- cheap LEDs (notably, Christmas lights) only light on half the AC wave, so they DO flicker at 50/60hz, not 100/120hz. Run an LED through a bridge rectifier, they flicker at 100/120hz, which people don't generally notice (and exactly the same as fluorescent). Add a filter cap, flicker is mostly gone. Most LED light bulbs I have looked at have at least a rectifier and capacitor.

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