I have a VTA ST120 that I would like to thoroughly check over to determine if everything is ok. I have had some KT88 tubes that have "red plated" and one outright failure.
Folks over at AK recommended that I do a detailed review of the amp before looking at the tubes as faulty.
I am looking for a step by step checklist to measure values in each circuit. I'm pretty sure I saw checklist with target values for assessing the ST120...I just can't seem to find any sign of it. I am new to electronic diagnostic/DIY, so a list a newbie could follow would be best. I am aware of the safety issues surrounding diy but am interested in learning to take care of my system. If anyone can give me a lead or link to something like this I sure would be grateful.