Differences in potentiometer taper codes

Frequently asked question regarding resistors, potentiometers, types, requirements, ratings etc.
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Coma
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Post by Coma »

Hi
I need to clear out this Q. Regarding pots and whether they are Lin or Log.

From Banzai site:

Potentiometer codes

USA and Asia:
A = logarithmic (also called 'positive logarithmic', 'audio', 'log' or '+ log')
B = linear ('lin')
C = negative logarithmic (also called 'reverse log', 'rev log', 'reverse audio', or '- log')

Europe:
A = linear (lin)
B = logarithmic (also called 'positive logarithmic', 'audio', 'log' or '+ log')
Y = negative logarithmic (also called 'reverse log', 'rev log', 'reverse audio' or '- log')


Will this depend on the country the pot was made in or where the pot was sold?

For example,

Where are Alpha pots made?
Will it have the same code if it's sold in EU, US or Asia?
I've bought pots from US and EU and don't know if the A100K or whatever is lin or log.
Anyway I can measure this?

Thanks!

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marshmellow
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Post by marshmellow »

Turn the pot half the way. Then measure the resistance between lug 1 and 2. If you've got about half the value of the pot value, it's linear. If it's definitely less, it's logarithmic, more than half it's reverse log.

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modman
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Post by modman »

viewtopic.php?p=38055#p38055

a = logarhythmic pot
b= linear pot
c= reverse logarhythmic pot

w = weird pot? :scratch:

W = Y = rev log ?
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kierc
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Post by kierc »

Sorry for the slightly OT question... but does it matter if you use a C500k (REV Log - Alpha) instead of a A500k (Log - Alpha) pot?
With the pot being the volume pot in a Fuzz Face?

Thanks,

Kier.

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