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I have a trimpot code(502) that after many searches I cant find the correct way to connect it the way I want and of course if it can be done.

As usual all potentiometers and trimpots as searched around the net are using the classic way of connection from the left leg until the middle rotation is 100 to 0 and from middle leg to right leg 0 to 100 as if we say it was a volume value the 0 and 100

So whatIi would like to know is how to connect my trimpot the way that from the left leg until the right leg rotation it gives me 0 - 100 or the opposite without the middle goes to 0 or even changes the value. I want my full left rotation to have the 0 or 100 and the full right rotation to have the other full or 0 value (like a volume knob)

Until now nowhere exists an answer or I am not searching enough.

Is there anyone who knows how to make the connections so it will work as I want or is not even possible and it needs something specific ?

Autistic
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Nocs
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  • I'm not too clear on what you mean. Does connecting the wiper to one of the two end terminals work? – Hearth May 21 '17 at 16:41
  • @Felthry yes all ways working fine, i am just searching for the way to connect the 2 L-R legs and the Wiper so i can get the result i need – Nocs May 21 '17 at 16:43
  • No, I mean, does that give you the result you want? – Hearth May 21 '17 at 16:44
  • @Felthry what is so hard to understand in my question ? Assume middle is the wiper leg ... – Nocs May 21 '17 at 16:45
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    Your phrasing is very unclear. What do you mean by "left leg until the right leg rotation"? What do you mean "without the middle goes to 0 or changes the value"? – Hearth May 21 '17 at 16:47
  • Does your radio knob in the middle goes to 0 volume ? or just have a full rotation from 0 to 100 left to right ? – Nocs May 21 '17 at 16:48
  • No, it doesn't. Draw a schematic so I can see how you're trying to use it, maybe? – Hearth May 21 '17 at 16:49
  • Got a multimeter? ring it out – sstobbe May 21 '17 at 17:29
  • You way you want a volume knob, but it sounds like you want a _balance_ knob (two stacked pots) or perhaps a crossfader (sources on both sides, signal at wiper). Drawing a diagram would help. – uint128_t May 21 '17 at 17:58

1 Answers1

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The usual way to connect a potentiometer as a volume control is:

schematic

simulate this circuit – Schematic created using CircuitLab

That will make the output vary from 0% to 100% as you turn the knob from fully counter-clockwise to fully clockwise. (the Left and Right terminals may be swapped, depending on how you look at the pot.)

If you want to use the pot as a simple two-terminal variable resistor, do this:

schematic

simulate this circuit

Peter Bennett
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  • Thanks peter for the effort and the schematic, i do connect them like the first one but it doesnt give me a full 0 - 100 on full rotation, instead it gives again 0 - 100 untill the middle :/ i tested 2 different 3 pin trimmers, i also connected both positive and negative from input in left and right and outputed from middle which i had a bad luck burning one trimmer and also until it burned a bit the 0 - 100 wasnt correct also as full rotation. – Nocs May 21 '17 at 18:29
  • Can you edit your post to include a photo or manufacturer/part number of your potentiometer, and a schematic showing your connections? (hit Control-M to open the schematic editor while editing your question.) Any pot I've used will give 0 - 100% over the full rotation using the volume control circuit I showed. – Peter Bennett May 21 '17 at 18:54
  • An "audio taper" pot resistance will vary logrithmically as you turn the knob, while a linear pot will vary linearly (50% value at half rotation) - perhaps you have an audio taper or other non-linear pot? – Peter Bennett May 21 '17 at 18:57
  • My trimpot is similar to this one http://www.dipmicro.com/?datasheet=RM065.pdf – Nocs May 21 '17 at 19:42
  • You are correct as to multimeter that i now doublechecked. As to the load that i use an led a small dc motor or something else it doesnt have the same way of 0 - 100 it falls 0 to middle allready – Nocs May 21 '17 at 19:53
  • The dc motor only does this way sorry all other led and multimeter indeed with the first connection it acts as a volume knob from 0% - 100% thank you all for your time, anyone knows why it does that in a small dc motor ? – Nocs May 21 '17 at 20:03
  • The characteristics of the load will affect what you see. An LED requires 2 - 3 volts before it will emit any light, so if you have 5 volts across the pot, you won't see any light below half rotation. The motor also won't run at very low voltages, and the resistance of the pot may not allow enough current to run the motor. – Peter Bennett May 21 '17 at 20:03
  • Thank you peter really appreciated, thanks for your time – Nocs May 21 '17 at 20:06