I'm creating a simple circuit and I need it to turn on when I press a button and stay on for the time that I choose on the timer (choose the time on a potentiometer, and it needs to go from like a few minutes to 3 hours). Eg. I choose 1 hour, press 'start', the light stays on for an hour and it turns off. The problem is that I can't find a timer that would work that way, can anyone help?
Ps: I don't want to use a microcontroller