alps 6 ch motorized pot help wanted

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I purchased 2 alps RK16818MG pots, and when connected according to the spec sheet, they do not attenuate audio. They are marked "AC only", and as you would expect, I can't measure any resistance with a DVM.
When connected, they pass audio but don't act like potentiometers.
Anybody out there with any experience or ideas? The website is just about useless. ANY help appreciated--
These were purchased on Ebay from a German concern, so my pleas for help from the vendor may not net much info.
 
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It would help to see a simple diagram as to how you've connected the pots. By the sounds of it, if it's not attenuating audio, then you may simply have them incorrectly wired. Have a look at this article here about wiring pots correctly. Also, the `DC only` that you read probably refers to the motor on the pot and means that it will not operate with AC - therefore, DC only.
 
Thanks, however I can't seem to find a link to the article you refer to. The DC only for the pot motor makes sense.
I just got a better diagram from the vendor, but it matches the factory drawing. I'm going to try connecting again when I get to the shop this evening. I'll get back with you later and send the diagram.
J-
 
Hey- Thanks for your help. I got a clearer hook-up diagram from the vendor, and the device is now acting like a volume control.
What threw me is the "AC only" tag (I may have said DC). I can't get a resistance measurement using a VOM or DVM, but it does attenuate an AC signal.
The other quirk I noticed is at signal levels above about 2.5 VRMS, the top half of a sine waveform squares at settings below about 50%, and the squaring worsens as the "pot" is turned down. So it looks like I may have to add some gain in the next stage to get my target output of 10VRMS.
Whatever is going on in there is certainly not a resistor.
For some reason I can't attach the .pdf file of the hook-up diagram with this browser, but if anyone is interested I can provide it from my home machine.
Again, Thanks
 
It would be real helpful if we knew what you were measuring? "Can't get a resistance reading," doesn;t specify what you are measuring. You can't measure resistance across the resistive elements or between the wiper and element? or you can;t measure resistance at the motor terminals?

And I went to Alps web site and entered that number (RK16818MG), and they have no record of that part number. Is that an Alps number, perhaps a typo, or is that a part number from a supplier like Mouser or Digikey or someone. I would like to look up the data sheet.
 
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