Peavey 6505 Bias Instructions
- 1). Remove the chassis from the enclosure of the 6505 with the screwdriver by loosening the screws mounting it in place.
- 2). Examine the schematic and locate the 15k ohm resistor marked R68. Find the actual resistor on the circuit board, noting the 10uf 160V capacitor immediately next to it.
- 3). Use the wire clippers to disconnect R68, making sure to trim as much of the leads back to the circuit board itself without damaging the board or surrounding components. Use the wire clippers to prepare a 2-inch piece of the 24AWG wire by stripping both ends of the wire approximately 1/8th inch.
- 4). Mechanically connect the 6.2k ohm resistor to a lead of the trimmer potentiometer other than the wiper lead. Mechanically connect the wiper lead and remaining outer lead together. Solder the mechanical connections using the soldering iron and solder. Solder the prepared wire to the wiper lead connection as well.
- 5). Turn the trimmer potentiometer fully clockwise. Mechanically connect the available lead of the 6.2k ohm resistor to one of the exposed leads of the 10uf 160V capacitor that was immediately next to R68. Mechanically connect the available lead of the 24AWG wire to the other exposed lead of the 10uf 160V capacitor.
- 6). Solder the mechanical connections of the trimmer assembly to the 10uf 160V capacitor using the soldering iron and solder. The 6505 is now biased to its coldest setting and can be adjusted to a desired level turning the trimmer pot counter clockwise to bias the amplifier "hotter."
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