If you own a La Crosse Technology WS-8117U-IT Atomic Wall Clock and after you change the batteries, the outside sensor seems to be no longer working, take the batteries out of both, put them in the outside sensor first, then put the batteries in the clock, then don't mess with either for 10 minutes. I have had mine over a year when it happened. I almost bought a new sensor but reading one of the product reviews on Costco and found the solution.