Hi,i am just curious to know why is the sound different (louder?) when the hole on the buzzer is obstructed.
void setup()
{
pinMode(2, OUTPUT);
}
void loop()
{
tone (3,1000,100);
digitalWrite(2, HIGH);
delay (500);
digitalWrite(2, LOW);
delay (500);
}
Probably the piezo is reflecting the sound into the breadboard which then becomes a sound board.
Note, you are calling this a piezo buzzer, is this a buzzer or a piezo speaker?