9090DB Volume Pot Won't turn off!

Fhamre

Super Member
I acquired a 9090DB that came with a volume pot that will not turn down the volume fully. No matter how much I tried to clean it,no change. So I replaced it with a donor part and all is well. Now I would like to see if that pot can be fixed. Is it a mechanical issue or?
Has anyone had success dealing with this issue?
The volume control portion is the two back portions. Its a 250K pot.
IMG_7160.JPG IMG_7162.JPG
 
Very likely the ground side of one or more of the the tracks is open circuit. This has the effect of changing it from a 'potentiometer' into a 'variable resistor'.
 
Last edited:
Can it be repaired?

Quite unlikely, it might have broken near where the terminal rivet goes through the track, you may even be able to see a crack with an eyeglass. Even if it is only a faulty or corroded rivet, it is fairly unlikely to be fixable.
 
This is a very common issue not limited to any particular model or limited to Sansui. It's been discussed many times over the years. I don't recall if anyone came up with a permanent fix for it because it's really not that big of a deal. Why would you listen to it with the volume turned to zero? Just turn the speakers off if you want to kill the sound output.

- Pete
 
I think I was assuming it was a bit more serious than just a sniff of audio when turned fully down, simply because of the description of the attempts to fix. :)
 
a sniff of audio
Is that a technical term?
Well I would agree its not the end of the audio world. Just checking to see it there was a relatively easy fix. If not the pot will just sit in my parts box.
I have read lots of different posts over the years where this issue or a similar one was encountered and attempted repairs made. Will do some more searching.
 
Just a guess but I'd think you could take some electrically conductive paint (or the stuff used to fix rear window defroster wires) and use it to jump the open section.
 
I like the term. :)

'sniff', however, needs to be quantified to be really useful.

I am thinking 1 sniff would be equal to the equivalent of the selector crosstalk/coupling you get on a typical receiver from a local FM station when the input or tape monitor switch is pressed with the volume fully up. Some receivers have considerably more than 1 sniff, some have less, some have the proverbial runny nose.
 
I acquired a 9090DB that came with a volume pot that will not turn down the volume fully. No matter how much I tried to clean it,no change. So I replaced it with a donor part and all is well. Now I would like to see if that pot can be fixed. Is it a mechanical issue or?
Has anyone had success dealing with this issue?
The volume control portion is the two back portions. Its a 250K pot.
View attachment 966576 View attachment 966577

Clean the carbon and fingers on the wafer with alcohol and a cotton swab. Wet it with alcohol and work it a few times, then swab it off with clean, dry cotton swabs. Don't "lube" the carbon and fingers. It will help some, but won't completely cure it.
 
Back
Top Bottom