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[on:]

hello,
I have here 10 alpha b10k potentiometers that look like this (link to datasheet):

http://docs.google.com/fileview?id=0B5QX_JA5-u2lYTRlM2Y4Y2UtNWVlNS00OGUwLTk5ODUtNDUzY2I4YzJkZTRh&hl=en

with the other potentiometers I've been using (rotary pots), I am used to 3 wires (ground, 5v, control)

these sliders however are confusing me greatly as they have 4 places to connect wires. I have been able to hook them up, but they display a limited range, get very hot, and begin to smell like burning. Can someone help guide me here? I need to know which wires go where?

thank you,
Zach

[Reply #1 on:]

You'll need to meter the pot to identify each pin.  Move the slider to the center, and measure the resistance between pairs of pins until you find the combination that reads the nominal value of the pot (10K in your case).  These are the end points, where you will connect 5V and Ground.  Meter from either one of those pins to the two remaining pins.  At least one of them should read about half of the nominal value (5K) with the slider in the middle of the pot.  This will be the wiper (where you read voltage to determine slider position).  

Now, it's possible that by hooking it up wrong you've damaged the pot, so if you can't get readings as I've described consider the pot toast.

[Reply #2 on:]

thank you, that was helpful

[Reply #3 on:]

Note that on the datasheet you reference, there are TWO pins labeled "2."  I would assume that this means that the three pins you are used to are 1, either 2, and 3.  ajb's technique should show which is which.