Ed Nauman owns a house situated just
uphill from some city-owned property that provides his yard with an endless
supply of pocket gophers. He has tried to defeat them from digging up his
yard, but without much success until he tried a siren with several annoying
tones. A simple timing circuit drives the siren with a low duty cycle. As Bill
Murray said in Caddyshack, "In
the immortal words of Jean Paul Sartre, 'Au revoir, gopher.'"