From: "Bill & Pookie"


> Seems to me that half wave rectified  60 cycle AC would give you a 60
cycle
> frequency with a 50% duty cycle.  Full wave rectification would result
in
> 120 cycle frequency with 100% duty cycle.  The human eye can only see
so
> fast so that movies at 30 frames per second (32?) appear flicker.  and
maybe
> the brighter the light is, the more it is imprested on our eyes and
less
> likely to flicker.  But I do think that sometimes we can see a
florescent
> light flicker (not sure if that is full wave or half wave, but back in
my
> days when neon bulbs were used like led's, they turned on at a high
voltage
> and turned off near zero volts.)

All that may be true, but I promise you that you can easily see the
flicker of LEDs flashing at <50Hz.  I like to use at least 70-80Hz for
PWM.  However, I am quite sensitive to flicker.

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