Thanks valvenator! I think I will try all AX7's later. See what happens. I honestly don't know which is the power transformer or output transformer. I'll get a better picture later too. What's your advice on trying a pair of 6L6's in this amp? I really have no way of knowing if these tubes it came with are even correct. It sat in a basement for over 30 years unmoved and 3 tubes were loose in the head when I got it. I know most vintage tube amps like Fenders used 6L6's. I thought 6V6's were mostly audio amp tubes..... but then I really don't know jack about it. And the front tremolo jack is an input jack. I plugged in and got sound, just no tremolo.