Experiment 4: Alternating Voltage

Getting to know

sinusoidal quantities, active (real), reactive, and apparent resistance/impedance, phasor diagrams
behavior of an RC and RL series circuit with different passive components at constant frequency
low-pass filter (behavior of an RC circuit at different frequencies)
RLC series resonant circuit: voltage across the resistor and impedances at different frequencies

Applying

Read the materials for Experiment 4 here.
They will be made public one week before the experiment.

Abb. 1: Simplified representation of an antenna

For this experiment you should

be able to apply and explain the following concepts:
1. phasor representation
  1. of harmonic signals
  2. of impedance quantities
2. complex impedance operators (e.g. $j \cdot X_L$)
3. cutoff frequency
4. series resonant circuit
  1. different voltages $U_R$, $U_C$, $U_L$ for $f\rightarrow 0$ and $f\rightarrow \infty$
  2. graphical and computational determination of the complex impedance $\underline{Z}$ of the circuit
  3. behavior of $\underline{Z}$ at different frequencies
  4. definition, behavior, and calculation of the resonance frequency
5. relationship between resonant circuit and antenna (see Abbildung 1)
consider the circuit when, instead of the voltage across the resistor $U_R$, the output voltage across the capacitor $U_C$ is measured.
1. What is this circuit called?
2. What is it used for?
3. What output voltage results for $f\rightarrow 0$ and $f\rightarrow \infty$?

Objectives of the Experiment