Peavey Butcher: Bias Mod Installation Guide

I'll take you through a quick tutorial on how to modify the circuit to enable a quick and easy bias adjustment when installing new power tubes.

The process is very simple and to make this video quick and to the point, I have omitted certain steps like removing the chassis and things like that. For a complete teardown and restoration of these amps check out other videos on my channel. To see the complete repair performed on this amp specifically you can click the link below
(will provide link when video is completed)

You may need to move a capacitor or two out of your way on the power board. Since most of these are due for a recap I would recommend replacing all the electrolytic capacitors in the amp. I have provided a complete parts list and a schematic guide through the link below. The file also contains the original Peavey Butcher operating guide. Enjoy and good luck!

https://drive.google.com/drive/folder...
Summary of contents:
Schematic
Board Layout
Layout of Bias Mod Components
Original operating manual

Parts List for Bias Mod:
Piher 25K Trim Pot
3.3K 1/2W Resistor
10K 1/2W Resistor

Parts list for recap (all axial leads, values updated for modern availability)
POWER BOARD
4 x 100uF / 350V
1 x 1000uF / 63V
2 x 220uF / 100V
PREAMP BOARD
4 x 22uF / 450V
1 x 22uF / 50V
OUTPUT BOARD
1 x 100uF / 50V