Hello. I need a simple delay circuit. When depressing button, it needs few seconds untill the relay actives. A circuit diagram or perhaps even a cheap circuit sold on eBay. If somebody knows how this circuit is called, that would help. I've tried "delay circuit" "count down circuit" "555 timer" etc but every circuit needs only a short triggering pulse to activate. Now I need one where you must hold the switch down for certain time.