by sKiZo Thu Nov 07, 2013 11:54 am
Dim bulb tester is what you're talking about, right?
That doesn't limit or reduce current ... it just gives another path for it to go if something goes horribly wrong. If the bulb lights, kill the power immediately or there's a good chance you're close to letting some of the magic smoke out of the amp. Track down the problem and try it again. Good to have an assortment of bulbs on hand too ... start high, then work your way down to maybe 25 watt before you call it a pass.
Variac is still a good idea, as that DOES bring the voltage up slow. Start around 80 just to tickle the circuits and make sure you've got good connectivity, then raise it in 10vac increments to operating voltage over the course of an hour or two. Lets the electrolytics reform properly as those can go weird over prolonged storage periods. In a lot of cases, a variac is a good thing to leave in line with the amp if the house current is normally high. Mine runs around 122+vac consistently, and these tubers prefer to see something around 117vac. Only concern there is it does take a while for a variac to stabilize, so you'd more or less have to leave it on all the time or plan waiting an hour anyway before turning on the amp. I can handle waiting five minutes for the tubes, but an hour is a bit of a stretch ... an ti ci pa shuunnnnnn!
Good you got it going though ... these old classics deserve a second chance! Just keep in mine you should at the very least be planning to replace any and all electrolytics AND any carbon resistors ... the clock is ticking on those if they're original.