Call me Rusty, need a little help

Actuallly, I'm Kinarfi and real rusty, any way I have a programmable Unijunction Transistor oscillator and need to use the capacitor charge voltage to add to another voltage, You can't load that part of the circuit. Anyway I don't know the correct way to bias a mosfet so it acts as a voltage follower. Would someone please fill in the blanks for me or should I use one of the transistor set ups in the schematic?
Oh Yea, I need to fill in the red box blank.
Thanks
Kinarfi

Posted in the other thread.

hi,

MikeMl has already shown you in detail how to use a HiZ buffer for this application in your other thread covering this project.

MikeMl said:

Posted in the other thread.

Click to expand...

Sorry Mike, slight time shift!....

I was trying to free up OP4 so I could use it as a buffer to OP3, guess not, better where it is.
Thanks
Kinarfi