A servo isn't just a motor — it's a motor with an angle sensor and a tiny brain that fights to hold the position you asked for. Combine a servo with the buttons you already own and you can build gates, meters, and games. This level also hands you control over electricity itself: a zener diode that pins a voltage in place, and a MOSFET that switches a load without drawing any current to do it.

New in the box

Micro servo (SG90) — A motor that turns exactly as far as you tell it.

9 V battery (PP3) + snap clip — Twice the push of the AA pack. Too much for an LED on its own — which is exactly why you learn to regulate it.

100 Ω resistor — Half a 220. The LED resistor for a regulated 3.3 V rail, where there is less voltage to burn off.

100 kΩ resistor — Ten 10 kΩs stacked. A pull-down for inputs that draw no current: MOSFET gates and logic pins.

Zener diode 3.3 V (1N4728) — A diode built to conduct backwards at exactly 3.3 V, so it pins a voltage no matter what the battery does.

MOSFET 2N7000 — A transistor switched by voltage, not current. Its gate draws nothing, so any signal can drive it.

with everything through L5, your box now holds 25 component types.

Level 5 · Control

New in the box

Ideas this level teaches

Projects at Level 5

What you can build so far