"Jim Wilkins" fired this volley in news:lgis3j$mjj
:

"Switching-mode power supplies are one of the toughest circuits most
engineers will ever have to stabilize."

Fffft! That has to do with load variation stability, not the quality of
incoming power. Most of the ones on the market today are good from 70VAC
to 240+ without any adjustments or switch selections, and they care not
it its full-wave, half-wave, or chopped up intermittent square wave, so
long as it averages within that range.

C'mon, Jim! I've been installing them, fixing them, AND designing them
from scratch since the late 1980s. They are NOT that sensitive to the
incoming power. They can be bitches to keep stable over wide ranges of,
and rapidly changing, load though; sometimes they even go into a 'chirp'
mode, which is always bad.

Lloyd