Ok, Larry talked me into designing him a 555 "coupler trigger." He doesn't want anything surface mount or programmable. I should have told him to find an engineer 40 years older.
Now, of course he has a problem. The thing gives him an output pulse when he removes the power. Since this is on a track powered train, he's worried it will trigger whenever he hits a dirty spot on the track.
So how do you keep a 555 from triggering when you power it down?
Don't you hate being held responsible for the outcome of a decision you opposed?