So I am going to incorporate some slide pots into a design and they have LED’s in them, my question is, do I need a Resistor inline to the + of the LED? or would the resistor be built into the pot?
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circuit on page 4 shows no inline resistor.
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No resistor in this. And it would be bad if it were, because that would limit your ways of driving the led 
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I seen that, just wasn’t positive - new territory for me lolol.
Thanks you 2
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Without any other evidence, you can only assume that what the diagram says is correct.
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They do give the LED characteristics on the following page, so you can figure out the minimum resistance needed.
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well guys - I think i effed up… so - can someone please tell me how to wire this slide pot… lol
I figured out the LED - but on my boards i had made, I absentmindedly made Pin 3 Ground…
So - should 1 be connected to ground and 3 be connected to In B?
Or do I have this all sorts of effed up?
I guess im a bit too dense to get how pots should be wired -_- lol
original schem
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Depends on which way you’ve mounted it. With the signal to pin 1 and ground at pin 3, you get max volume when the wiper is near pin 1.
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dammit … Pin 3 is up top 
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lmao i might build it and put it in my case upside down lmfao.
im so pissed i did this without asking people how to wire it.
I seem to have done the same with my S&H’s from what @ChristianBloch discovered.
i’ll get it one of these days… maybe…
It seems which way to wire them makes no sense - but the way @fredrik stated it - it makes a ton of sense.
Here is a question -
Is the “Signal” ALWAYS going to go to Pin 2?
And then is 1 and 3 always ground and positive but wiring is dictated by turn/mounting direction ?
With the usual numbering (as in the schematic above), the end positions are pins 1 and 3 and the wiper is pin 2. If you feed in the signal at pin 1 and connect pin 3 to ground, you get the full signal at wiper pin 2 with the wiper (slider) closest to pin 1, and no signal (ground) at the other end.
See https://learn.sparkfun.com/tutorials/rotary-switch-potentiometer-hookup-guide/background-and-theory for a bit more on this.
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oh that link is invaluable! thank you 
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I was just wiring some rotary pots today and caught a mistake on the first one. I always have to strain my brain to make sure I get them right. If you’re looking at the pot from the front with the pins downward, pin 1 is on the left and pin 3 is on the right, and the wiper is shorted to pin 1 when fully counterclockwise. So for a voltage divider normally you want pin 1 at ground and input voltage on pin 3. For a variable resistor you want pins 1 and 2 if you want resistance to increase as you turn clockwise, 2 and 3 if you want it to decrease.
(In the Gate Grinder there are two pots and I wanted one to control the clock rate (low to high) and the other to control the gate width (short to long), and if you think about it that means CCW is long RC time in one case and short RC time in the other, and managing to get that right the first time on the PCB I considered a personal triumph.)
Never used slide pots but I think I’d have an easier time keeping them straight, since the proximity of the wiper to each end is immediately visible.
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