DLowndes

I've found a better circuit diagram with more pages here: Line 6 POD XT Series Ultimate Tone | SynthXL - FREE Service Manual That has the Revision E circuit which is the board I have. Interestingly, what the power section labels as +8V is the half wave rectified signal that I measure as between 12-15V, so the PCB does match the circuit diagram, it's just that what's called the +8V supply is not the output from the 8V regulator that one would expect!

POD XT Service Manual.pdf - YGG Channel Portal In the above linked manual, on the 3rd page (identified as sheet 7 of 9), it shows the drain of the mosfet Q1 connected to the +8V line, but it seems to be connected to the unregulated 12-15V line that the 8V regulator uses - see the attached image. Just to be clear, the 12-15V is a lumpy half rectified signal when viewed on a scope. Can anyone confirm this?