DaveWW
Well-known member
Hi folks,
As promised I'm posting details of fitting the SB-2 kit from London Power to my Fender Champion 600.
It didn't go as smoothly as I'd hoped mainly because although there are few parts to actually install the instructions are purely schematic so you have to have some knowledge of schematic circuit diagrams to figure out the installation. I did manage to figure out most of it but my extremely limited knowledge was not quite enough so I sought help from Alnicomagnet who supplied the stuff for my other mod's. The other problem was the very limited space available in the amplifier.
Basically, turning down the "power scaling" pot reduces both the voltage going to the anode, and screen in equal measure.
The "drive compensation" pot is a dual gang 1 meg audio pot wired in parallel. It acts just like a normal master volume control.
After shorting out a few resistors the amp now works fine It does exactly what it says on the tin and I can now get nice tube distortion at volumes you can talk over although ther amp was never a gain monster to start with.
Pic's follow
Kit Contents
Assembled PCB
Other Components
Power Scale Pot Assembly
All Parts Assembled
Ready To Go Back In the Amp Cab
Front Panel Layout (need some labels and a new knob :lol: )
Needs some tidying up now which I'lll do later. It would have helped quite a bit if I'd used different couloured wires from the PCB and some form of plug and socket would be of great help when taking out the main amp circuit board.
Anyway after a bit of trouble I'm now very pleased with the result. It works even better with pedals and the sensitivity seem increased as well
Dave
As promised I'm posting details of fitting the SB-2 kit from London Power to my Fender Champion 600.
It didn't go as smoothly as I'd hoped mainly because although there are few parts to actually install the instructions are purely schematic so you have to have some knowledge of schematic circuit diagrams to figure out the installation. I did manage to figure out most of it but my extremely limited knowledge was not quite enough so I sought help from Alnicomagnet who supplied the stuff for my other mod's. The other problem was the very limited space available in the amplifier.
Basically, turning down the "power scaling" pot reduces both the voltage going to the anode, and screen in equal measure.
The "drive compensation" pot is a dual gang 1 meg audio pot wired in parallel. It acts just like a normal master volume control.
After shorting out a few resistors the amp now works fine It does exactly what it says on the tin and I can now get nice tube distortion at volumes you can talk over although ther amp was never a gain monster to start with.
Pic's follow
Kit Contents
Assembled PCB
Other Components
Power Scale Pot Assembly
All Parts Assembled
Ready To Go Back In the Amp Cab
Front Panel Layout (need some labels and a new knob :lol: )
Needs some tidying up now which I'lll do later. It would have helped quite a bit if I'd used different couloured wires from the PCB and some form of plug and socket would be of great help when taking out the main amp circuit board.
Anyway after a bit of trouble I'm now very pleased with the result. It works even better with pedals and the sensitivity seem increased as well
Dave