There isn't one.

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There isn't one.

Posted by Tre' (P) on April 18, 2025 at 15:49:31

In Reply to: You didn't include the load of the input of the next stage posted by Ralph on April 18, 2025 at 14:27:58:

The shunt resistor is the grid resistor for the next stage so there is no
"load of the input of the next stage".

And even if there was, that would not change anything. The load would be in parallel with the value of the shunt resistor of the voltage divider and if the shunt resistor value resistor changes value, the amount of attenuation of the voltage divider would change. Just not as directly as in this case, but change it would. You can take that to the bank.

Ralph, you went from saying "it works exactly the same" and "The level of the channel that is not being turned down does not change" to "before that sort of thing would be noticeable". Either something is different or it's not. Whether or not it's noticeable has nothing to do with what I am (and have been) saying.

Using a pot with a grounded center tap vs. using a pot without a grounded center tap as part of a balance control...the two will not operate the same. Not in a technical sense. And noticeable or not, the voltage will change when the shunt resistance changes. And by saying "before that sort of thing would be noticeable" you admitted it.

You could have just started there and then proceeded to explain to me why that won't matter in practice.

Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"

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Follow Ups Full Thread

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)

Follow Ups

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

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