On Wed, 13 Apr 2011 19:22:37 -0400, "Stormin Mormon"
wrote:

So, it's cheaper to put a half wave rectifier in, instead of
a second coil of heater wire? I rather doubt that.

I don't remember the details, but I know quite a few DO work that way
- and they also used 12 volt DC blower motors, without a transformer,
by basically using the heater element as a rheostat..