Peter Pan wrote:

Always thought the singing to be related to the harmonics due from
phase control (the sound isn't 60 Hz), so the capacitors might not like
seeing all that harmonic current.

Also putting a capacitor parallel to the load shouldn't make it dc. The
capacitor had to be rather large, not to mention the need for some
rectifiers. This could be a way to filter out the harmonics on the
lamp.


Going further back in the thread, the discussion was on filtering
rectified AC.

bud--