Hi I am working on a pseudo 5F4 build using Hammond organ transformers. Due to not having a bias tap I took the RobRob rout and tapped it from my rectifier socket at pin 6 as stated on his website. But now for some reason, I am only getting voltage at pin 4 and not pin 6. I am suspicious of the diode being open. Am I on the right track in my sleuthing? Also should the ground and tip of the output jack for the speaker show continuity to ground?