What does the AM forum hive mind say about how to bring up such fils after a long inactive period?
The H&K's have them and I am nervous about just throwing full juice on them. They are 5 volt @ 7.5 amps per tube.
Any recommendation to heating them slowly when first lit? small variac in the primary n slowly let them burn for a while at half scrote?
What say you poeple that know more than me?
The question is prompted by hearing many stories about how the larger tubes like 100th's with such fils have failures. The fils in these tube are much shorter in length.