# Difference between revisions of "Lab 3 TF EIM"

RC Low-pass filter

# 1-50 kHz filter (20 pnts)

1.) Design a low-pass RC filter with a break point between 1-50 kHz. The break point is the frequency at which the filter starts to attenuate the AC signal. For a Low pass filter, AC signals with a frequency above 1-50 kHz will start to be attenuated (not passed).

Enter your values for and

 R C

2.)Now construct the circuit using a non-polar capacitor.

3.)use a sinusoidal variable frequency oscillator to provide an input voltage to your filter.

4.)Measure the input and output voltages for at least 8 different frequencies which span the frequency range from 1 Hz to 1 MHz.

 Hz Volts Volts

5.) Graph the -vs-

# phase shift (10 pnts)

1. measure the phase shift between and as a function of frequency . Hint: you could use as an external trigger and measure the time until reaches a max on the scope .

# Questions

1. Compare the theoretical and experimentally measured break frequencies. (5 pnts)
2. Calculate an expression for as a function of , , and . The Gain is defined as the ratio of to .(5 pnts)
3. Sketch the phasor diagram for ,, , and .(30 pnts)
4. Calculate an expression for the phase shift as a function of , , and graph -vs . (20 pnts)
5. Compare the theoretical and experimental value for the phase shift . (5 pnts)
6. what is the phase shift for a DC input (the limit as frequency goes to zero) and a very-high frequency input?(5 pnts)