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Civilize the mind, but make savage the body.

- Chinese proverb

Why not put a multimeter to it and check the potential? If its 120V (I'm assuming you're in North America) then do some loop checks - i.e. Does it go back to the electrical panel? Often there is a clue in the panel, such as an electricians penciled in note on what this is.

If you can get your hands on a Fluke meter (or equivalent) you can clamp on the prongs, induce a signal and then follow the wire through the walls to see where the hell it comes from - i.e. the phone company, security system, NSA surveillance, etc.

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Remember - It's important to be comfortable in your own skin... because it turns out society frowns on wearing other people's

If there were only a place that dealt with a wide variety of electrical components, some place maybe that sold radio's out of shack? Kind of looks like a homemade lashup of an EU two prong power cord, except it only has one key.



If you have one of these nearby, they might, might know what it is. But I'd throw a multimeter on there just to see what what voltage it's providing.

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The secret of a long life is you try not to shorten it.
-Nobody

Is your house from the 70's by any chance? The cable looks kind of like it might be 300 ohm twin-lead FM/TV antenna wire. Additional clues would be gained from where you found that wall plate - is it near an obvious location for a TV or stereo? If you've never been up in the roof of your house, you may find a big antenna array up in there.

Sometimes the wire will have printing on it, indicating the gauge and other details. That can help you identify the intended use.

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Less is more.

I'm not positive but it looks like something called a JST RCY connector. Typically used for low voltage stuff, so in a house it could for speakers or a TV antenna.

+1

Bingo! Thx. Actually found a similar plate on eBay just to confirm. 300 ohm Tenna-Grip TV plug wall plate.