A sound meter lets you measure how loud a sound is.
PART 1: ASSEMBLE THE CIRCUIT
The LM358 IC and the polarised capacitor need to be orientated correctly. See below for details.
PART 2: VISUALISING DATA
STEP 1: Open this file and upload it to Arduino.
This sketch displays the value of A0 (microphone input) on the Serial Monitor. You should see a running display of numbers.
STEP 2: Close the Serial Monitor. You want to free up the pin for the Serial Plotter.
STEP 3: Open the Serial Plotter.
Make some sounds close to the microphone and see how the display changes.
PART 3: MEASURING THE SOUND LEVEL
STEP 1: Upload the following program into Arduino.
STEP 2: Open the Serial Plotter. Make some sounds and see how the value changes on the Serial Plotter.
The program in Part 3 introduces local variables. Below describes the difference between local variables and global variables.