Scott 299B balance potentiometer question

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Posted by JRMA (A) on April 8, 2025 at 18:53:02

Looking for advice on replacing a troublesome balance pot on my Scott 299B integrated. I have deoxed the pot and still have some intermittence.

My question is: there is an extra terminal opposite the wiper terminal. On the schematic is says "1meg tap @500k" with an extra line on the wiper symbol.

I have not had any luck finding a 4 terminal pot. Is it possible to replace it with a three terminal and do some rewiring to make it work. Also of note is the schematic for the kit version of this (LK72) show only a three terminal

So, looking for advice from others with more experience than I!

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Topic - Scott 299B balance potentiometer question - JRMA 18:53:02 04/08/25 (17)

This is a shunt-style balanced control. - Ralph 08:18:33 04/09/25 (15)

RE: This is a shunt-style balanced control. - Tre' 16:13:19 04/15/25 (13)

Do you mean the wiper? - Ralph 10:02:43 04/16/25 (12)

RE: Do you mean the wiper? - Tre' 17:07:35 04/16/25 (11)

FWIW if you just have a grounded wiper it works exactly the same. - Ralph 08:15:36 04/17/25 (10)

No it doesn't - Tre' 09:48:01 04/17/25 (9)

Recommend you try it :) nt - Ralph 14:00:30 04/17/25 (8)

I don't use a balance control but I can see that it would work. Just differently. - Tre' 14:04:18 04/17/25 (7)

Without the grounded tap - Ralph 14:15:05 04/17/25 (6)

RE: Without the grounded tap - Tre' 18:46:37 04/17/25 (5)

Again, you should try it. nt - Ralph 11:56:06 04/18/25 (4)

OK. I did. - Tre' 13:25:34 04/18/25 (2)

You didn't include the load of the input of the next stage - Ralph 14:27:58 04/18/25 (1)

There isn't one. - Tre' 15:49:31 04/18/25 (0)

OK. I will. nt - Tre' 12:51:17 04/18/25 (0)

RE: This is a shunt-style balanced control. - JRMA 15:20:48 04/14/25 (0)

RE: Scott 299B balance potentiometer question - JKT 20:39:34 04/08/25 (0)

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