Electrical and Electronics: Module

Module 26A: Tuned Circuits and Oscillators (Core)

Suggested time: 15 - 20 hours

Level: Intermediate

Prerequisite: Module 25

Foundational Objectives

To read and interpret schematic diagrams and other technical documents.
To use appropriate terminology for electricity or electronics in context.
To become knowledgeable about the various principles and characteristics of electricity and electronics.
To analyze circuits and predict their output.

Common Essential Learnings Foundational Objectives

Discuss how components such as capacitors and inductors react to AC.
To strengthen students' knowledge and understanding of how to compute, measure, estimate and interpret numerical data, and when to apply these skills and techniques, and why these processes apply within the particular framework of electronics. (NUM)
To develop students. abilities to see comparisons within electronics and give reasons for their positions. (CCT)
To develop students. skills and abilities to identify their learning needs. (IL)
To enable students to understand and use the vocabulary, structures and forms of expression. (COM)

Learning Objectives	Notes
CAPACITORS
26.1 To describe the charging and discharging process in a capacitor. (COM)	Set up a circuit then measure the length of time required for a capacitor to charge and discharge.
26.2 To calculate the capacitive reactance of a circuit. (CCT, NUM)	Provide the students with a schematic diagram of a circuit showing capacitor values and frequency.
26.3 To explain the phase relationship between voltage and current in both a series and parallel resistive-capacitive (RC) circuit. (NUM)	Introduce students to the concept of phase relationships through the use of vector diagrams.
26.4 To define and calculate the "time constant". (COM, NUM)	Set up an RC circuit and calculate and verify the "time constant".
26.5 To list four applications of time constants. (CCT)	Study several schematics diagram and determine the use of the RC network.

INDUCTORS

26.6 To explain how an inductor operates and the factors affecting inductance. (COM, CCT)	Provide students with information regarding the characteristics of an inductor.
26.7 To calculate the total inductance of series connected inductors. (NUM)	In order to do the calculations, provide the students with a schematic diagram showing values.
26.8 To calculate the total inductance of parallel connected inductors.	Provide a schematic diagram showing values.
26.9 To calculate the inductive reactance of a circuit.	Provide the students with a schematic diagram showing inductor values and frequency.
26.10 To compare the phase angle between voltage and current in an inductor.	Compare the phase angle of an inductor to the phase angle of a capacitor.
26.11 To list two applications for simple resistive-inductive (RI) circuits.	Provide schematic diagrams showing RI networks and describe the action.

Module 26B: Tuned Circuits and Oscillators (Core)

Suggested time: 15 - 20 hours

Level: Advanced

Prerequisite: Module 26A

Learning Objectives	Notes
IMPEDANCE AND RESONANCE
26.12 To calculate the impedance, current or voltage of a circuit. (NUM)	Provide students with a schematic diagram showing all but the required parameters.
26.13 To calculate the phase angle in both a series and parallel circuit. (NUM)	Provide a schematic diagram showing all required parameters.
26.14 To define resonance. (COM)	Indicate through the use of a vector diagram, the concept of resonance.
26.15 To calculate the resonant frequency of a network. (NUM)	Provide the students with a schematic diagram showing the value for the inductor and capacitor.
26.16 To calculate the value of the capacitor required for resonance.	Provide a schematic diagram with the value of the inductor.
26.17 To calculate the value of the inductor required for resonance. (CCT, NUM)	Provide a schematic diagram with the value of the capacitor.
26.18 To list the characteristics of a series resonant circuit. (COM, IL)	Have students set up a circuit and observe the effect on current and voltage as the circuit approaches resonance.
26.19 List the characteristics of a parallel resonant circuit. (COM)	Have students set up a parallel resonant circuit. Describe the effect of voltage and current as the frequency approaches resonance.
26.20 Define bandwidth and explain the factors affecting bandwidth.	Have students list the factors that affect bandwidth and sketch a graph showing bandwidth on a resonance curve.
26.21 Define "Q" in terms of the ability of the circuit to discriminate between frequencies.	Explain the concept of "Q" in a resonant circuit. Give examples of the effect of different values. Provide a schematic diagram showing all required parameters.
26.22 To calculate the bandwidth of a circuit.	Provide a schematic diagram showing all required parameters.
26.23 To draw a typical resonance curve for both a series and parallel circuit. (COM)	Have students draw a schematic diagram showing all required parameters.
26.24 To draw the circuit and explain the action of band-pass, band-stop, low-pass and high-pass filter networks. (CCT)	Provide students with the description of each filter and its circuit application.

OSCILLATORS

26.25 To describe the conditions required for oscillation to occur. (COM)	Research and list the factors that enable oscillation.
26.26 To identify LC Oscillators. (CCT)	These inductive capacitive circuits are often called tank circuits or flywheel circuits. Locate and name the type of oscillator in the circuit: Armstrong, Hartley, Colpitts or Clapp.
26.27 To construct a basic series-fed Hartley oscillator. (IL)	Construct the circuit and make changes in the circuit and note the effect on the circuit operation. Calculate the resonant frequency. Observe the output waveform on an oscilloscope and record the frequency. Shunt the capacitor in the resonant circuit with another capacitor of equal size and note the effect on the frequency. Remove the bias resistor connected to the transistor while the circuit is oscillating and note the effect on the circuit. List typical applications and limitations of the Hartley oscillator.
26.28 To construct a basic series-fed Colpitts oscillator, make changes in the circuit and note the effect. (IL)	Construct the circuit and check the operation. Calculate the resonant frequency. Observe the output on an oscilloscope and note the frequency. Change the feedback capacitor in the tapped capacitor arrangement and note the effect on the oscillator. Use three samples ranging from small to large in the value of the capacitor. List typical applications and limitations of the Colpitts oscillator.
26.29 To construct a crystal oscillator circuit and observe the results. (IL)	Construct the circuit and check the operation. State what determines the natural frequency of the crystal. List the advantages and disadvantages of using a crystal oscillator.