Driven RLC Circuit

rlc circuit

What It Shows

The amplitudes and relative phases of the voltages across the individual elements of a series RLC circuit varies with the frequency of the driving voltage. The voltages of the three elements plus the driver are plotted simultaneously on an oscilloscope. Changes in the amplitudes and phases can be seen in real time as the driving frequency is varied.

rlc scope

How It Works

A 10Ω resistor and 1µF capacitor are connected in series on a plywood board, which has the corresponding schematic symbols painted on it. External to the board are a 20µH coil and a function generator, which connect to the board at inputs near their corresponding schematic symbols. Adjacent to these inputs and to the R and C are BNC connectors for the oscilloscope. The resonant frequency is approximately 1.2 kHz.