David and Dale: YES on all:
As we were power elecronics designers since 70s' we have a collection of Variacs, the best are indeed the old Staco and GenRad with ACV RMS and AC .
Mains in UK EU = power line in USA
The voltage mentioend ar efine.
Alternate is an un metered variac and use the knob calibration for V .
Add aseries AC ammeter (or clamp on whith splitter) but the clamp on are no accurate.
Today we are working on a trusty 7603 mainframme TEK with blown linear PSU, that draws normal till a few sec at 30-60V
Then lets losse with 2-4 A curretn , smoke and smells...
Its a dyiung lytic on the rectifier board, an on FP can
Enjoy,
Jon
Jean-Paul