Reply To: Older kit, need coherent instructions

[Andy]

It’s possible that the tube is not functioning. Id probably look first for some open joint or misplaced ground somewhere before I replaced it though. Make sure only the places that are supposed to be grounded are grounded.

Also… It looks like there is a 1 MEG resistor at the center-tap place not a 100Ω. If you swapped those you could have some issues. 100Ω is Brown Black Brown and 1M is Brown Black Green