## EE 212 Lab

### Lab 6: Frequency Response of Circuits

Prelab 6

The purpose of this lab is to experimentally construct the frequency responses
of two circuits. The circuits to be studied are the passive RLC circuit shown in
figure 1 and the active network shown in figure 2.

1. Frequency response of RLC circuit.

- Construct the circuit shown in figure 1.
- Let
*v*_{in}(t) be a 1 V_{p-p} sine wave for which
you'll vary the frequency.
- Use your prelab results as a guide as to what frequency range should be
used and measure the frequency response (magnitude and phase) of
*V*_{out}(jω)/*V*_{in}(jω).
Note the function generator and oscilloscope display frequency in Hertz and
your plots are likely versus frequency in rad/sec, so make sure to
convert whichever way you choose to keep the units consistent. Take
extra points in regions where the magnitude or phase change quickly.
- Compare
your results with the calculated values plotted in the prelab by
recording the experimental data on top of the calculated prelab data.
- How would one describe this circuit?
- Does this passive circuit ever yield a gain larger than 1 (0dB)? If so,
how is this possible?

2. Frequency response of active circuit.

- Construct the circuit shown in figure 2.
- Let
*v*_{in}(t) be a 1 V_{p-p} sine wave for which
you'll vary the frequency.
- Use your prelab results as a guide to what frequency range should be used
and measure the frequency response (magnitude and phase) of
* V*_{out}(jω)/* V*_{in}(jω).
Note the function generator and oscilloscope display frequency in Hertz and
your plots are likely versus frequency in rad/sec, so make sure to
convert whichever way you choose to keep the units consistent. Take
extra points in regions where the magnitude or phase change quickly.
- Compare
your results with the calculated values plotted in the prelab by
recording the experimental data on top of the calculated prelab data.
- How would one describe this circuit?

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