Project 2: an LED flasher with buzzer

This second circuit activates a buzzer every time the LED turns on.

For this project you will need the following components:

  • Resistors (optional): 1x 100Ω resistor

    • resistors for this project are optional, because the piezo/buzzer already provides 225Ω resistance inherently built within it

    • if you choose to include a resistor in your circuit, the buzzer’s sound will be less loud compared to a circuit without resistor, however the LED will flash with more precise intervals

    • the colour bands on the resistor will be: brown, black, brown, gold

  • Semiconductors: 1x 5mm flashing light-emitting diode (aka LED)

    • if you’re unsure how to tell a Flashing LED apart from a normal LED - look closely inside the head of the bulb - you will see 2 small square chips

  • Batteries: 4x AA batteries (each AA battery has 1.5 Volt. This means 4x AA batteries will add up to 6 Volts total across the circuit)

  • A battery holder with 2x leads (a Positive and a Negative terminal)

  • A breadboard

  • any leads and hookup wires you need to create the circuit connections on the breadboard

Design view in Tinkercad:

Schematic Diagram:

Assembled project: