A little over 20 years ago my wife designed and made these simple concrete sprinkler guards. They've worked well for us. I just made a form to make some more, so I thought I'd write up a blurb on it. It doesn't deal with electronics, but since there are a number of do-it-yourselfers here, I thought some of you would appreciate the idea and want to make your own. They're simple, cheap, and effective.