I recently bought, as a finished product, a brand new ST-120 with octal board. The left side amplification is much louder than the right. I wish to trace down the source of the problem. To do that, I believe i need some voltages or resistances that I can check to see if I can localize the problem. If anybody has a recommended triage approach, that would be helpful. Right now I do not have any voltage or resistance data that I can use to check anything. i have an oscilloscope on order, but it isn’t here and I don’t know how to use it. Here is what i have done so far:
Chop stick prodding of all joints and examination for cold joints - re-wet a few
swapped input and output wires, all tubes, verified that its the RHS amplification that is the problem
Any links to tables of voltages or resistances I should expect while measuring the board, either off or on, would be greatly appreciated. Also, any recommended triage approach: do this then that then the other, etc. would be greatly appreciated.