> 60Hz is fast enough to hide any flicking.

Only if you hold your head still and don't move your eyes. Add a capacitor
and smooth it out. Sorry, flickering LEDS's are a pet hate of mine.
Hundreds of Hz and even several kHz are quite noticeable under some
conditions. Some car LED brake/tail lights annoy me, tired wandering eyes
at night obvserve these as a mesmerizing train of dots, doesn't do anthing
to help road safety.

Back on subject though... yes power in the resistor will be very hgh. For
single wave rectifier add an inverse parallel diode across the LED so
reverse voltage will not exceed about 0.7V, as LED's rated at only around
5V or so reverse. Could use a full bridge rectifier and get 120Hz, smaller
filter capacitor. RC circuits are also good, reduced power disspation, but
do pay attention to electrical safety, and also consider high frequency
transients on the AC power line. They have a low impedance path through
the capacitor so ideally you should take this into account and put over=20
voltage/current mechanisms in place.



--=20
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