Residents of the small Ohio city of North Olmsted had a strange mystery on their hands for weeks: Their key fobs and garage door openers suddenly stopped working. It wasn't every key fob every time, but it was happening enough to make clear that something screwy was going on, reports the New York Times. Amateur sleuths armed with meters joined forces with the local cable and utility companies and even AT&T to try to crack the mystery. Local NBC affiliate WKYC had someone canvass the neighborhood with a spectrum analyzer, without much luck. At one point, power was shut off to an entire block, and still the interference continued. Finally, investigators zeroed in on one house in particular from which a strong signal seemed to be emanating.
Inside, they discovered a homemade device the homeowner had built to alert him to movement in the house when he was in the basement. They yanked its battery, and the mystery was solved, reports Cleveland.com. “There was no malicious intent of the device,” says North Olmsted Councilman Chris Glassburn. “There will be no further interference, and the resident has agreed to not make such devices in the future." The unidentified homeowner had no idea his gizmo was causing so much trouble. It put out a 315 megahertz signal, the same one used by many key fobs and door openers. “He has a fascination with electronics,” explains Glassburn. (Read more strange stuff stories.)