Connect the components as shown in the Guitar Tuner Circuit Diagram below. The push buttons are connected without pull up/down resistors because the Arduino’s in built pullup resistors will be used.

In circuit diagrams, a pull-down resistor is typically represented by the standard resistor symbol connected between the input pin and the ground symbol. ... These include general digital circuits ...

Arduino RF Transmitter Circuit Diagram. Our wireless doorbell project will require a transmitter and receiver circuit each with its own Arduino board. ... A pull-down resistor of 10kohm is connected ...