№ 2 · you build it
Turn the knob, fade the light
Turn the knob and the light goes from bright to almost gone.
- 1Tap the battery, then the knob.
- 2Tap the knob, then the resistor, then the red light.
- 3Tap the red light, then the battery.
NOW Tap the battery, then the knob.
What to look for: Turn the knob one way and the light is bright. Turn it the other way and it nearly disappears.
Why it works: The knob is a squeezer for electricity. Turn it one way and the path gets tight, so only a trickle gets through and the light goes dim. Turn it back and the path opens up, and the light gets bright again.