200kbx2 potentiometer

Copa1934

My ears are bleeding
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I've found a variety of Dual Taper pots for use as a volume control, but all have 2 rows of 3 contacts where the one in my system is 2x4. There are legs that, on the backside of the board, connect with the balance control mounted just below the volume.

I have a STA-2500 receiver and the only thing wrong with it, presently, is the volume which doesn't work anymore at the lower volumes. OK, I know, I could just listen at higher volumes. Now that we've gotten that jest out of the way maybe we can work on a suitable solution.

I thought about using something lower or higher value, but not sure what the repercussions are. I assumed (wrongly?) that a (ex) 300k would mean the dial would have to be turned more for equivalent level. If I got this backwards, no worries. I would be just fine with a different value, that may require turning the volume more for more equivalent "level", as long as it fits.

Anymore info required? Let me know. I can post images if needed.

Any solution will help MANY RS receiver owners as they share the same or similar pot for the same vintage receivers. I believe the one I have installed now came from a STA-2600 or 2700, can't recall now. It's also the most common part to go out.
 
Put 100k. Should be an upgrade. Higher value = higher distortion. You will not lose "sensitivity" in the volume control.
 
This should be close

http://www.ebay.nl/itm/130820551892

"Higher value = higher distortion": I'd like to see the proof for that claim....
That "looks" nice. Probably an upgrade. Only issue is the shaft. Probably long enough, but mine is a "half shaft" or notched. Not really sure the correct term. The tip has a flat spot that engages the knob.

I could change the knob, too, but I'd like to go for something closer if possible. Any thoughts on the value? How it would impact the settings? I can appreciate a higher quality unit having less distortion, but going from 200k to 100k or to 300k, how would that impact the "loudness" based on relative position of the knob?
 
but going from 200k to 100k or to 300k, how would that impact the "loudness" based on relative position of the knob?

It wouldn't.
Simply put they act as a voltage divider: setting it halfway results in half the voltage. Absolute value does not matter for the "loudness" perception.
(halfway electrically speaking; volume pots are not linear)
200k and 250k are close enough to not have negative impact on the rest of the circuit.
 
Have you tried Deoxit or similar to cure the pot?
It's weird, honestly. I did exactly that, months ago. I actually do this from time to time with all my equipment due to the area we live in which is predominantly farming. So dust is really bad here.

Anyway, this didn't seem to do the trick, then. I put the receiver aside and decided it was time to try again, which is why I made this post. I changed out the "board" with one from another receiver, newer model RS receiver. Took the top off, took some images for reference. Decided to do what others have suggested (from more recent posts) and work the "twisted" wires to improve connections. I also decided, while I'm in there, to un-plug and plug-in all the connectors multiple times.

Well for the first time in years she's playing beautifully. And the display is now working (both power indicators and tuner dial were non functional). I found, this weekend, a source for a replacement pot which I'll order. If it's not correct I can return it.

Thank you for your help!
 
It's weird, honestly. I did exactly that, months ago. I actually do this from time to time with all my equipment due to the area we live in which is predominantly farming. So dust is really bad here.

Anyway, this didn't seem to do the trick, then. I put the receiver aside and decided it was time to try again, which is why I made this post. I changed out the "board" with one from another receiver, newer model RS receiver. Took the top off, took some images for reference. Decided to do what others have suggested (from more recent posts) and work the "twisted" wires to improve connections. I also decided, while I'm in there, to un-plug and plug-in all the connectors multiple times.

Well for the first time in years she's playing beautifully. And the display is now working (both power indicators and tuner dial were non functional). I found, this weekend, a source for a replacement pot which I'll order. If it's not correct I can return it.

Thank you for your help!
I should have re-read before posting. The replacement board was changed out a year or so ago. After the initial cleaning months ago, I put it away and basically gave up.

I wonder if maybe I used too much lubricant and impeded the functionality, if only briefly. I guess it's also possible working the wiring inside may have helped some. The volume control board only has one connector, all the rest of the connections are solder.

I inspected the original pot, before replacing, and it was quite evident the carbon(?) was worn away, so replacement was necessary. Be nice if these were repairable, like replacing surrounds on drivers.
 
Glad you got it working
Having worn out one (cheap) pot, I'm thinking ordering at least one spare would be a good idea. I've really enjoyed this receiver. It's the only receiver I own that I bought new.

Again, thanks for the input.
 
Back again. I'm revisiting this due to the intermittent behavior of the volume, mostly NOT working at lower volumes. Clearly this is due to wear. I noticed, this time, a more complete description of the pot (similar to the link JohanH provided) and it mentions the 4th leg being used for Bass Boost. Any thoughts on this? I'm assuming there is additional circuitry for that leg. I'm assuming, also, that the Bass Boost falls off as the volume is turned up. Doesn't make sense to add boost at higher volumes. Likely it's not linear either.

Thoughts?

Thanks
 
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