You are direct coupling the source follower to the grid presumably so you level that at the gate using you’re -80v rail and earth voltage devided to shift the gate, the source follows with a step change so measure resulting level at source when adjusting output stage bias with youre pot which sets the gate level. You don’t require output tube to set this section dc conditions such that no danger. You can do this because you’re making dedicated power supply for the Nmosfet. Yes
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
You are direct coupling the source follower to the grid presumably so you level that at the gate using you’re -80v rail and earth voltage devided to shift the gate, the source follows with a step change so measure resulting level at source when adjusting output stage bias with youre pot which sets the gate level. You don’t require output tube to set this section dc conditions such that no danger. You can do this because you’re making dedicated power supply for the Nmosfet. Yes
Just looked at you’re diagram and see you’re bias arrangement would work. So maybe best you stay on you’re plan, which you’ll no doubt build in bias adjustment.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein