[DCASAZZA]

Alan is right. The taps pretty much determine the voltage. The rehostat takes care of the little high/ little low after the load of the tube is brought to bear. Ive never had to fix one but it might be worth you taking a realy good look to make sure there is no "creative wiring" form a previous owner. I would suspect if the transformer was bad there would be a noticable loud hum, unusual heat, smoke, or all of the above. Good luck

Dave