Controller for garage door controller. Caps are electrolytic (polarized). Resistor may or may not exist in garage door opener, but it's included here to prevent short for main open/close button. Caps are for light and lock on/off. Current changes when button is pressed, and is detected by the opener. 18V 60Hz hasn't yet been verified.
The controller also includes an LED with resistor in series (not included here). Uncertain if opener sends DC to power the LED, along with AC control voltage.
