Phase converter question

Well, I'm about ready to build a static phase converter to test an old
3/4 hp 3 phase motor I got with a lathe and am planning on using the
design at:

http://web.wt.net/~hmsc/phconv/phconv.htm

But since I know very little about regular old A/C electricity, as opposed
to the digital kind, I was wondering if someone could be a bit more
specific about the type of dual primary transformer that is being used to
derive the AC neutral in the second diagram. I don't want to sound like
too much of a bozo when I walk into my electronics store to buy one. I guess
the only real question is how many amps the thing needs to handle. Could
someone explain what this transformer is really doing? Layman's terms would
be helpfull here. Are inputs 1 and 2 on the 120 volt side and inputs 3 and
4 on the 220 volt side?

Also, will this converter be able to run the motor in reverse? How about
immediatly reversing the motor? Is it ok to switch the motor on the 3 phase
side of the converter or should the switch be on the input side?

Thanks for all the help and wish me luck,
Drew

--
Drew Rogge
drew@...