[Frank Stearns]

"Richard Crowley" writes:

wrote ...
Does using a single diode as a half power step introduces RF noise as
well?

No, because it doesn't cause any significant "slicing" of the
mains sinewave form (like a SCR dimmer does).

But it might cause visible flicker as the filament(s) are getting
only every-other pulse of current.

IIRC (and correct me if I'm wrong), *some* power diodes will have a nasty
transient at conduct/non-conduct. This might or might not be a problem in
the RF range, but a snubber cap parallel with the diode should take care
of the problem.

Some of the higher-end electronic dimmers (US$40+ vs. $2.95) will be a
little quieter but indeed a variac is the best way to go.

One approach is to fit the wattage you need for the light you need while
running full on (no dimmer), and then have another set of worklights if
you need more light from time to time.

Frank Stearns
Mobile Audio

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