Volume Pot Issues: Sansui 5050

[DarrylY]

Good evening. New here; picking up stereo repair as a hobby in my (semi) retirement. Have had some success fixing eBay finds, etc.

One of our friends passed away and his widow gave me his Sansui 5050 that he bought new as a younger man. It's in beautiful condition. The right channel, however, never goes totally silent when the volume control is all the way down. It's loud enough that it's something I want to fix and the unit is too nice (and sentimental) to ignore the problem. I don't know the history of how long it may have been this way.

I've removed, cleaned and deoxed the pot as best I can. Appears to be a 250K pot. I failed to take pre-cleaning readings, unfortunately, but the post-clean numbers are:

fully CCW:
Inner pot 1-2 4K, 2-3 254K
Outer pot 102 0 ohms, 242K

fully CW:
Inner pot 1-2 258K, 2-3 0 ohms
Outer pot 1-2 243K, 2-3 0 ohms

The 1-2 4K reading is anomalous. But is it bad enough to cause this?

 

[Brian1970]

That does seem like the cause of your problem.

 

[DarrylY]

Just to close the loop for anyone with the same issue. The pot was the issue, and a replacement is unobtainable. It's a PCB mounted 250K x2 with a loudness pot, pretty obsolete in today's world. However, I found a lug mount pot with the same shaft length. 8 wire jumpers from the board and soldered to the new pot, mounted the pot directly to the front face. It's mounted 90 degrees from the other pots, so I had to grind off the locating tab. Looks OEM and works great. Part number: Alps 6DB, 250KohmBX2. First image is the replacement pot, second is the original one. Found it on eBay for $3.90!