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Your first Electronics circuit build

Now that you understand the components, it’s time to put them together. We will build a simple circuit that connects an LED to power via a resistor.

The Circuit Diagram​

Before we touch the breadboard, look at this schematic. It shows the flow of electricity: from the Power Source → Resistor → LED → Ground.

Step-by-Step Assembly​

Follow these steps exactly to ensure your circuit works and your components stay safe.

1. Add the Resistor​

  • Take your 220 Ω or 330 Ω resistor.
  • Pick a spot in the middle of your breadboard across the gap.
  • put the resistor with one leg on either side of the gap.
  • Place one end in hole A10 (this connects it to the LED's long leg).
  • Place the other end into any hole in the Red (+) Power Rail.

2. Connect the LED​

  • Push the Long Leg (Anode) into hole E10.
  • Push the Short Leg (Cathode) into hole E11.

3. Connect the Ground Wire​

  • Take a jumper wire.
  • Plug one end into hole A11 (this connects it to the LED's short leg).
  • Plug the other end into any hole in the Blue (-) Ground Rail.

4. Powering the Board​

If you are using an ESP32 to power your board:

  1. Connect a jumper wire from the 3V3 (or Vin) pin on the ESP32 to the Red (+) Rail.
  2. Connect a jumper wire from a GND pin on the ESP32 to the Blue (-) Rail.
Check your connections

Double-check that the short leg of the LED is the one connected to the Blue (-) Rail. If the LED is backward, it won't light up, but it won't break either!

What should happen?​

Once you plug in your ESP32 or Power Module, the LED should glow steadily.

  • Not lighting up? Try flipping the LED around.
  • Still nothing? Ensure your power wires are pushed firmly into the breadboard rails.