I have to admit Stuart that I'm still a little confused about DA#1. It was stated on here a few weeks ago that only the very earliest versions of Alts. needed to be externally excited with a "switched hot" lead. It was further stated that any of the alts. made in the last (and I forget the number of years here but it was a LOT) years would self-excite with residual magnetism.
I sure would like to get this settled once and for all in my little pea-brain!