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jeb

100k pot jittering ! a solution instead of throwing the pots away ?

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hello,

i use 10k pots that are working fine !

the 100k pots are jittering (it's not a soldering problem).

the "U = R I" law implies that I is too small to give accurate voltage !

i understand, but now I have to deal with these pots !

about the jittering : around

of 0 no problem, aroud of 127 no problem, but in the middle : it does

for exemple 56 67 56 55 57 56 55 56 (approx 4 messages sent per second).

is there another solution than changing the pots ???

(i don't want to replace all these 20 pots ! it's an expensive model !)

putting some capacitor ? some other solution ?

thanx in advance !

jeb

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Well, you can put a resistor in parallel with the pot to reduce the resistance.  This will change the response curve as well tho..

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hello,

thanks a lot !

a resistor bewteen 0v and the middle pin of the pot ? or between 5v and 0v ?

i think it is the first solution ? i tried, and it seems to work !

by the way, as the pots are "A100K" (logarithmic). is there a mean (by choosing a

well adapted resistor value) to get a "linear curve" ??

(i saw it is possible to have a log curve with a linear one by adding a resistor,

the converse may be true too, is it ?)

thanx !

jeb

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by the way, as the pots are "A100K" (logarithmic). is there a mean (by choosing a

well adapted resistor value) to get a "linear curve" ??

I think your problem isn't a matter of the resister value. Your problem are the LOG type pots.

As far as I remember, they won't work. And if they do, you'll never get the taper linear.

greets

Doc

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you'll never get the taper linear.

yeah... you should use them for the DIY-mixer you should build now  ;)

matthias

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in fact there are two problems :

* the jittering : and this has nothing to do with the curve of the pot, it has to do with the

value of the pot : 100k is too much !

* the curve : the pot has a log curve, and if i add a resistor (in order to solve the first point :

  in order to have a lower resistor value for the pot !) the "log" curve that the pot already has is

  amplified....... so i wonder if it is possible to solve both problems in one :

to add a (or several) resistors to reduce the 100k (too high !) value of the pot AND to modify

the curve in order to 1) if possible reduce the log curve to linear      2) if not possible, at least

not amplify the log curve with the added resistor !

thanx in advance !

jeb

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1 and 2 are not gonna happen I'm afraid. MIOS_AIN_DeadbandSet may be your only help.

Yeh. I think you need new pots. I know it sucks but that's why the pages say 10K linear  :-\

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