[sdiy] A transformer question.

[Tom Bugs]

Hi,

A quick question about twin primary transformers for which I've not been 
able to find answers...

If there are twin 115v primaries.. (ie series for 230v and parallel for 
115v)
- should this be able to cover Euro vs UK ranges of c.220v to 240v?
- and would it cover US 120vAC and 110vAC in places like Cuba?
- how can one deal with the 100v in Japan (other than replacing the 
trafo with a different spec one?)

I'd guess there's a bit more to it too - dependent on current draw, 
trafo type & spec, etc..

Any help greatly appreciated!
Ta,
Tom