Uusually done with multi-tap with centre-tap ground, with two diodes
per multi-tap instead of bridge.

I seem to remember the transformer needs to be considerably bigger to
avoid a dip on one bus causing a dip on the others.  Which is why it
is rarely seen except where linear regulation is needed for other
reasons.

--=20
James Cameron
http://quozl.netrek.org/
--=20
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