w_1:(continued)

Each LED is linked to power differently.

The Yellow one: through a variable resistor

The Green one: through a swich.

The Red one: I took a risk of connecting it to a 5V regulator while skipping 220 ohm resistor. It was just for a few minutes.
I wonder what will happen it it is kept for long. Does anybody know the answer? I'm resisting a lure to try it.