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Hoffman Amps Forum image Author Topic: Question about 250 dual pot on tos  (Read 3622 times)

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Offline 67polara

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Question about 250 dual pot on tos
« on: September 25, 2010, 10:32:27 am »
Hello:

Having a problem finding a 250k dual pot for the master volume on the TOS.  Would it be OK to parallel 330K ohm resistors with the 1 Meg dual pots to bring it to the correct value?

Tony

« Last Edit: September 25, 2010, 10:38:14 am by 67polara »

Offline tubenit

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Re: Question about 250 dual pot on tos
« Reply #1 on: September 25, 2010, 11:05:55 am »
Until I got both TOS amp switched over to VVR, I used a 500k dual gang pot with 470k resistors and that seemed to do fine. 

I also currently have that 500k dual pot/470k resistors on my Tweed OD lite & it works fine on there.

I'm thinking your plan with 1M and 330k should work fine. You could also use 270k instead of 330k.

With respect, Tubenit

Offline 67polara

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Re: Question about 250 dual pot on tos
« Reply #2 on: September 25, 2010, 11:18:34 am »
Will do thank you.  Any wattage concerns with the resistor, 1/2 watt ok?  A 270k calcs out to 212.6k and a 330k is 248k. Are you sure I should use the 270K?  What about the Resistance not matching between the two pots due to tolerances?  Should I put a trimmer on one side to match them?

Tony
« Last Edit: September 25, 2010, 11:27:43 am by 67polara »

Offline Geezer

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Re: Question about 250 dual pot on tos
« Reply #3 on: September 25, 2010, 11:40:34 am »
   Cunfuze-us say: "He who say "It can't be done" should stay out of way of him who doing it!"

Offline toobzilla

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Re: Question about 250 dual pot on tos
« Reply #4 on: January 30, 2025, 09:12:43 am »
Hello:

Having a problem finding a 250k dual pot for the master volume on the TOS.  Would it be OK to parallel 330K ohm resistors with the 1 Meg dual pots to bring it to the correct value?

Tony


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