I replaced all the old electrolytic capacitors but noticed I missed two of them. The amp has a 120 volt relay using a hard to find cheater cord that they used to use on a vacuum tube television sets. Hadn't had one of them probably in 40 years but I found one at Surplus Sales of Nebraska. I'm going to be switching at via another set of 12 volt relays isolating it from the solid state switching of modern radios.. I may only use this with my Yaesu vacuum tube ham rig.