Replaceing bass pot on amp?

[Dani Pace]

The bass control on my Fender Princeton Chorus is shot and I need to replace it. The circuits seem fine but the pot has a bad rough spot and goes from off to about 9 with nothing in between. Anyone know what the correct replacement part number is? I'm pretty good with a soldering iron so I can do the work myself, I just want to use the right (best) replacement part. Thanks

 

[Farview]

The thing I always did was take it out and read the back of the pot.

 

[gusfinley]

yeah..

This is a simple enough repair. a 1M audio pot is common for a BASS control...

 

[Light]

Just remember, there are caps in there which will store voltages which can kill you. You should really drain them before you start mucking around in there. The macho way is to take a plastic handled screwdriver, and touch it to the cap and the chassis (which the chassis grounded, which is to say pluged in). Nice big spark and a big bang that way. Otherwise you can make a little tool to drain it. Mine is just a wire with aligator clips on both ends (insulated aligator clips, thank you), and a 100K 5W resistor in the middle. Make sure the resistor is well insulated by covering it with lots and lots of shrink tubing). Then, measure all the caps to make sure they are not carrying any voltage.

I'm serious here. These are not "ouch, that hurt" voltages, these are DOA voltages.


Light

"Cowards can never be moral."
M.K. Gandhi

 

[Dani Pace]

Thanks for the reminder about the caps. I've been "bitten" a couple of times and didn't like it even a little bit. Fortunately I learned to be careful before I grabbed anything holding enough of a charge to inflict any serious damage to myself.

 

[-=¤willhaven¤=-]

You could try spraying some contact cleaner in the pot first. I've seen some pretty crusty pots come back to life with some cleaning. Otherwise, replacing it should be pretty straightforward.

 

[Dani Pace]

Thanks for the idea Will, but this pot is way beyond a simple cleaning.

 

[ggunn]

The bass control on my Fender Princeton Chorus is shot and I need to replace it. The circuits seem fine but the pot has a bad rough spot and goes from off to about 9 with nothing in between. Anyone know what the correct replacement part number is? I'm pretty good with a soldering iron so I can do the work myself, I just want to use the right (best) replacement part. Thanks

From http://www.ampwares.com/ffg/schem/princeton_reverb_aa1164_schem.gif, it appears to be a 250Kohm pot, assuming that the Chorus and Reverb models are the same in that respect.