Turning a centre tap transformer into dual secondaries

Hi Guys,

I have a few large EI core power transformers salvaged from faulty home theatre receivers. They all seem to be a centre tapped transformer rather than dual secondaries as is my preference.

So the question is:

Can I 'cut' the 2 sides of a CT to create dual secondaries?

1426938520.jpg

Its not quite clear on the photo, however the 0v clearly has 2 wires going to the 'spike'. Could I separate these 2 wires and create 2: 0v-21v-42v secondaries or would I be doing something silly that I am not forseeing?
 
differences in phase....? so long as you respect what your sending to the rectifier all should be good (21+, 0 , 21- and 21+, 0 ,21- ( in that order) 'cause the windings are not likely to change direction with respect to the primary) and given two independent rectifiers, no.
 
Get the phase backwards with windings in series and you get zero volts with a very cold transformer. Get the phase backwards with windings in parallel and you get zero volts and a very hot transformer. In the former case there is zero current, in the latter there is “a lot” of current (effectively Shorted secondary).

If two completely separate windings are independently rectified the only thing that matters is the polarity of the DC at the outputs. Swapping the AC inputs to either rectifier dont matter at all because the diodes will steer the currents in the proper direction.
 
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