I think that I have found out what is wrong with the negative bias. I found a diode with 158 vac going in and only 6 VAC coming out. I don't see any type of Bias pot anywhere , 1/2 of A 12AX7 tube might be how it adjusts the voltage but I'm just trying to get the negative bias working again through the diode and e Caps at this point , I can get it to regulate later on after I get it back working again. It goes through a few resistors and into two 150 volt capacitors put in backwards with the negative side Hot and the positive sides goes to ground. I'm guessing that the negative voltage should be going through the diode and into the two backwards e caps ? , The flat side of the diode is towards power in , The Red wire on the bottom of the picture. If I am testing it right ? And I don't know what kind of diode type it is to replace it , It's a really Old Metal looking diode (maybe zenor) made in 1960 . See picture.
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