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So i have a bunch of 100k pots. But i need a few pots that goes up to maximum of 100 ohms. I have tried to put resistors in series with the pot to limit the range and it does work, but the pot gets to sensitive and about 80% of the pots range is useless.

Is it possible to do anything about this or do i have to buy one for my needs?

I'm asking because i have around 20+ 100k pots. So it seems pretty dumb to buy a new one if i can "modify" them. All the pots are linear ones.

Thanks!

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  • \$\begingroup\$ Not clear what you're looking for. Do you want a range of 0-100 ohms or 100-100K ohms? For the latter, putting a 100 ohm resistor in series should work. For the former, the best you can do (without active components) is to put the 100 ohm resistor in parallel but, as you noted, you'll end up using very little of the pot's range. \$\endgroup\$
    – DoxyLover
    Jul 18 '16 at 3:17
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    \$\begingroup\$ @Xane - There is a reason that parts catalogues and online retailer's web sites offer a plethora of different ohms sizes in various parts families. Buy the correct part for your circuit needs. \$\endgroup\$ Jul 18 '16 at 4:24
  • \$\begingroup\$ @DoxyLover I want a range from 0-100 Ohms. The mainproblem is that i end up with a little range.. But i guess i have to buy one for my needs then. \$\endgroup\$
    – Xane
    Jul 18 '16 at 12:04
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Strictly speaking, if you put a 100 ohm resistor in parallel with a 100k pot, then the result will be in the range 0-100 ohms (give or take a tiny percentage).

However, in practice, this will be pretty useless. It will be highly non-linear, with all of the control at one end.

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  • \$\begingroup\$ With a 100R in parallel you'd end up with something like this graph, where you've got a non-linear pot which is good up until about 2k (or 1/50th of a turn). I'd recommend just buying one \$\endgroup\$
    – Doodle
    Jul 18 '16 at 12:35
  • \$\begingroup\$ Thanks for your answer. I see, is it possible to make it more adjustable with 2 pots? One for course and one for fine adjust, or will i still get the same problem? \$\endgroup\$
    – Xane
    Jul 18 '16 at 14:27
  • \$\begingroup\$ @Xane your problem is that the resistance range of your pots is so far from what you want that just adding resistors in series or parallel isn't really going to fix it. \$\endgroup\$
    – Simon B
    Jul 18 '16 at 15:33
  • \$\begingroup\$ @SimonB Got it, Thanks everyone, i ended up ordering a 100 Ohm ten turn pot from ebay cheap. that should do the trick! Cheers. \$\endgroup\$
    – Xane
    Jul 19 '16 at 15:18

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