Here’s a quick and easy weekend project, a simple metal detector! We all know 555 timers are very useful and pop up in a wide range of projects, but did you know a metal detector is one of them?

“Any time you try to get 2,200 kids through two metal detectors, it takes a long time,” said Greg Manior ... The cost of the detectors, which range from $8,000 to $10,000 each, is not a ...