Lab #5

Adding a Capacitor and Resistor

You must adfd a resistor and capacitor to the input and output of your circuit for protection. They will regulate the DC voltage in a circuit so they don’t over charge the audio input/output.

Calculations

R2 = 10k ohms

R1 = 10k ohms

Gain = 1 + (R2 / R1)

Gain = 1 + (10k / 10k)

Gain = 1 + 1

Gain = 2

Calculations

Highest – R1 = 10k, R2 = 10k

Gain = 1 + (10k / 10k)

Gain = 1 + 1

Gain = 2

Lowest – R1 = 10k, R2  = 0

Gain = 1 + (0 / 10k)

Gain = 1 + 0

Gain = 1

Calculations and Analysis

Rin = 10k

Rf = 20k

Gain = -Vin * (Rf / Rin)

Gain = -1 * (20k / 10k)

Gain = -1 * 2

Gain = -2

In this photo the output is inverted and has two times the voltage of the input.

Calculations

Highest – Rin = 5k, Rf = 10k, Vin = 1

Gain = -1 (10k / 5k)

Gain = -1 * 2

Gain = -2

Lowest – Rin = 5k, Rf = 0k, Vin = 1

Gain = -1 (0 / 5k)

Gain = -1 * 0

Gain = 0