Quoted from lhammer610:
That is very interesting. I have never had slingshots need caps and would not put them on. But drop targets should never need a cap.
You are correct about drop targets, I actually wrote standup targets. Slings respond better too however with caps. Mechanically a ball compresses a slings rubber for quite a while so they don't need caps as much. I have more than one Bally that had factory caps on the slings however. If you put a scope on the strobe lines, they are only being read at ~ 120 Hz, it is pretty slow, so they are refreshed every 8.3 msec. The actual window of time that the switch can respond is at best 5% of each 8.3msec window. So 95% of the time the switch is not being monitored.
Even with caps it is not all perfect, get a game like Xenon where the ball can rattle between pop bumpers for quite a while. You will get 20 bounces in a row, then the machine misses one, there is a slight pause, then it starts throwing the ball around again.