We are almost ready to leave on our year long cross-country RV adventure, and Baila created a doorbell for her bunk. If her shade is down, we can ring her doorbell. If she is available, the sign will light up! My favorite part of her invention, is the /and/ bit which provides feedback while a visitor is pressing the doorbell!
How To Make It
Build Circuit: Power + Wire + Button + Buzzer + Double AND (1st Input) + (2nd Input) Wire + Roller Switch + (Output) Wire + Branch = (Top Channel) Long LED + (Right Channel) Long LED + (Left Channel) Long LED