Re: 240V -> 120V Converter for Stereo Projectors!

[P3D Michael Kersenbrock <michaelk@xxxxxxxxxxx>]

> > By the way I don't know why this thing needs to be electronic.  A simple 2:1
> > transformer would do the same thing.

Actually, one only needs a 1:1 transformer or a 240 V.C.T. transfomer because
one can wire it up as a autotransformer.  One doesn't get any isolation that
way, but little boxes with a diode or maybe a triac/quadrac sort of arrangement
doesn't give isolation either.  

I've used the dual-primaries of a 120V to something-or-other xfmr hooked up as 
an autotransformer to temporarily generate 240 from 120 -- which is something 
that rewiring the lightweight converter box might not be able to do.  :-)

> 
> The problem is, to handle 1600 watts with a transformer means the 110V
> secondary has to carry 15 amps of current.  This needs #14 wire (or
> preferably #12 to be safe), and a transformer wound with this wire gauge
> would be HEAVY.  The advantage of the electronic converter is its low

For resistive things or for things that rectify to DC, that'd probably work fine.
Some motors may not like the waveform, some are a bit pickier than others. Try
(carefully) and see.

Mike K.
WB4IOJ






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