OK I did some searching and I couldnt get what I was looking for, the 250k trimmer on the phase 90 is there a voltage I need to measure when setting it or just tune to taste?
I am getting a very good phase at present but it varies in character when I change the trimmer I just wnat some kind of reference point to set it to if there is one
Cheers
There is good way to know ahead of time. That pot sets the amount of back bias on the phasing JFETs to get the best phasing sound. There's probably a way to figure it out mathematically given that you know the Vgsoff of the JFETs, but it's far simpler to set it where it sounds best.
Thanks RG your a saint, I was pondering on this for a little while, only on bread board right now as I am looking to incorporate a few tweaks before I fire up Eagle and make a layout. you got to love Xmas yo get plenty time off work to build :)