We are having the exact same problem. Looks like we either got a dud or the thing is a piece of junk.

Even with the battery, the thing doesn't work! I dropped a coin on the floor and it didn't register. I placed the sensor on the BBQ pit lid (solid metal) and the thing beeped once. You'd be better off burying the piece of **** and then buying a real metal detector so you know where it is. That way you'll ensure this **** never sees the light of day again! Cheap Chinese ****!

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