Lectures (ENGR-2300)

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Experiment 1 Project 1
Experiment 2 Project 2
Experiment 3 Project 3
Experiment 4 Project 4
Experiment 5 Quiz Review
Experiment 6 Background
Experiment 7 Tools
Experiment 8 Class Preps

Prep Videos

Videos should be viewed before the class meeting indicated, except for the first two videos which should be viewed before the first day of class (Before Course, Class 1)
Videos are posted on YouTube and linked from here. If you do not see a video posted, please let me (Prof. Schoch) know.

Before Course (A Quick Tour of Electronic Instrumentation Websites, recorded Fall 2014 so links to piazza, staff, etc are dated), Class 1 (Welcome to Electronic Instrumentation), Class 2 (The Voltage Divider & Team Responsibilities ), Class 3 (Spec Sheets), Class 4 (Frequency Dependent Circuits),Class 5 (Some Key Concepts & Addressing Each Configuration 3X), Class 6 (Reverse Engineering in Our Study of Inductors), Class 7 (Inductors & Transformers), Class 8 (Motor Project), Class 9 (DC Motors), Class 10 (Feedback & Op-Amps), Class 11 (Math with Op-Amps & Ideal vs. Real Circuit Components), Class 11 Extra (Real Op-Amp Differentiators), Class 12 (Damped Harmonic Oscillators), Class 13 (Thevenin Equivalent Sources), Class 14 (Indirect Measurements for Control Applications ), Class 15 (Beam Velocity Measurement Using DIY Guitar Pickup), Class 16 (Math, Estimates, Multi-Stage Circuits, Specs), Class 17 (Relays), Class 18 (Threshold Detection & Relays), Class 19 (Analog Discovery Digital Measurements - First Slide incorrectly labeled as Class 18), Class 20 (555 Timer), Class 21 (Switch Debouncing), Class 22 (Diodes), Class 23 (AC to DC Conversion), Class 24 (Zeners, LEDs, Photodiodes/Phototransistors), Class 25 (Pulse Modulation), Class 26 (Circuit Functionality).

Videos on Specific Topics

These videos were prepared to address particular topics including tools and skills used in EI (e.g. Analog Discovery boards, collecting and displaying data) and fundamental topics that are generally found in multiple homework, experiment or project assignments (e.g. Thevenin Voltages and Resistances, Transfer Functions ...). Either browse through the topics or use the 'find' function to locate what you are looking for. Also included are cross-cutting issues that appear over and over. The most useful of these is the set of videos on the Voltage Divider, which, it turns out, can be used to introduce just about any topic in EI.


  1. Experimental Techniques, Data Analysis ...
    1. Telling A Story With Data In this video, we look at data taken in a solar cell experiment, identify the key features of the data and then tell a story based on the cause of each feature. This video should be thought of as a simple case study of how we can use data obtained using some kind of electronic instrument (e.g. oscilloscope, data logger, etc.) to tell a story.
    2. CR Circuit Study In Electronic Instrumentation, we address essentially every circuit configuration three times: once from basic theory (paper and pencil calcs), once from simulation (PSpice) and once from experiment (Analog Discovery or Mobile Studio). In this video we look at a simple filter circuit made from a capacitor and a resistor, with the output across the resistor.
    3. Identifying and Labeling Plot Details PSpice, Mobile Studio, Analog Discovery, etc. are all great at producing interesting plots of circuit simulations and experiments. All have some exceptionally helpful features that help us identify and label details in the plots so they are easy to find. Here we look at some of the basic features of PSpice and Analog Discovery Waveforms.
    4. Quick Online Tour of Lissajous Resources There are two goals for this video: 1) To provide a bit of background on Lissajous Figures for Electronic Instrumentation students. 2) To show an example of using online resources in combination with the many tools we have to investigate a new topic.
    5. Loadlines A simple intro to the powerful technique of using loadlines to determine operating conditions for diodes.
  2. Analog Discovery
    1. Simple Audio Instructions for Analog Discovery (similar to Simplified Directions for Audio Measurements with Mobile Studio)
    2. Analog Discovery Visible Light Comm Demo (similar to the Optical Comm Demo with Mobile Studio)
    3. Analog Discovery Board w Lissajou - Explore basic functionality of Analog Discovery
  3. Mobile Studio
    1. Mobile Studio Triggering Tutorial
    2. Mobile Studio Software Tutorial
    3. Mobile Studio - Simplified Directions for Audio Measurements
    4. The LabView Talking Voltmeter - from Mike Kleinigger
    5. Heatsink Testing - From Mike Kleinigger
    6. The Threshhold Executable - A separate program written to control the Mobile Studio, can be used to create a thermostat or other devices used in design projects.
    7. Optical Communication Demo - Shows a very simple demo created with the Mobile Studio
  4. PSpice
    1. PSpice Demo Pt 1: A voltage divider problem using the student version (9), setting up the project and starting to place parts in the circuit.
    2. PSpice Demo Pt 2: Completes the drawing of the circuit
    3. PSpice Demo Pt 3: Sets up and runs the simulation and displays voltages at selected points in the circuit.
    4. PSpice Demo Pt 4: Using the cursor to read info from plots, copying plots and circuit diagrams to the clipboard so they can be included in reports.
  5. Components
    1. Identifying Electronic Components Playlist: (4 Videos - Select 'Play All') Identification of resistors, potentiometers, capacitors, inductors, crystals/oscillators, relays, transformers, batteries, fuses, diodes, transistors, bridge rectifiers, integrated circuits, switches, LEDs and LED displays, piezo buzzers/elements, electret condenser mics, identifying components on a circuit board, manufacturer logos.
    2. Combining Resistors: A simple introduction to combining a network of resistors.
    3. SimplifyingResistiveCircuitsProblems 1 This video has two goals. 1) Provide a little help with HW1 problems. 2) Show how useful simplifying circuits can be before attempting to analyze them. One of the key ideas to grasp in analyzing any system is that, for given operating conditions there are usually only a few key components that determine most of the features of the system. By eliminating any that are not very critical, analysis is easier and confidence in results is improved.
  6. Winding a Coil: Some practical info from a YouTube video.


  1. Problem Solving Methodology: Example problems in which aspects of solution methods are emphasized. In particular, usually the goal is to simplify, simplify, simplify ... until some aspect of the solution can be obtained using known concepts. This is a new set of videos begun Fall 2014. Please add comments to YouTube under the video if you have suggestions on how to improve the videos or for other topics to address.
    1. Schmitt Trigger Built from a 741 Op-Amp (from Spring 2014)
    2. Zener Diode Analysis (essentially the same analysis applies to other diodes, including LEDs)
  2. Complex Arithmetic: Some basics for complex numbers, useful for Exp 2 and later experiments.
    1. Complex Numbers Pt 1: Quick review of complex numbers, complex plane, polar representation and Euler's Identity
    2. Complex Numbers Pt 2: The real and imaginary parts of ratios and magnitude of complex numbers
    3. Complex Numbers Pt 3: The phase of a complex number.
  3. Transfer Functions
    1. Intro to Transfer Functions Pt 1: The impedances of R, L, and C; RC circuit transfer function; simplifiying transfer functions.
    2. Intro to Transfer Functions Pt 2: The RC transfer function at low and high frequencies (not zero and infinity); corner frequency.
    3. Intro to Transfer Functions Pt 3: Corner frequency and summary of major features of transfer functions; phase; physical meaning of low and high frequencies.
    4. Intro to Transfer Functions Pt 4: Comparison of resistive, inductive and capacitive impedances at low and high frequencies; replacing L and C with open and short circuits; discussion of open and short circuits.
    5. Intro to Transfer Functions Pt 5: Both types of RC circuits.
    6. Intro to Transfer Functions Pt 6: RL circuit corner frequency; real vs. ideal inductors; using the ideal capacitor to model real capacitors.
  4. Transformer Properties
    1. Part 1: General intro to solenoid properties and principles of transformer operation.
    2. Part 2: More on transformer properties and notation.
    3. Part 3: First assumption and beginning to set up the circuit equations
    4. Part 4: The second and third assumptions for ideal transformers, continuing to set up the circuit equations.
    5. Part 5: Deriving the ratio of secondary to primary current and the input impedance of a transformer. The voltage ratio is not derived.
    6. Part 6: Final comments on modeling and design of transformers.
  5. Inductance Formulas
    1. Part 1: How to use simple formulas to predict inductance values for home made coils.
    2. Part 2: Long solenoids, online resources to check your answers.
    3. Part 3: Why ideal models are useful.
  6. Thevenin Equivalent Sources
    1. Thevenin Overview: Voltage Sources
    2. Thevenin Example
    3. More Thevenin Examples (Solving problems from HW5)
    4. Problem 1, Quiz 2, Spring 2015 (Solving in more detail than in the solution)
  7. The Voltage Divider (Investigating the Voltage Divider both as a Practical Circuit and a Gateway to Most Concepts in EI)
    1. Part 1: What is a divider and how does it work if we build one?
    2. Part 1.1: Measuring input and output voltages to fully characterize the operation of a circuit, with and without a load.
    3. Part 2: Deriving the formula for an unloaded and a loaded divider
    4. Part 3: Building and testing a loaded voltage divider. Both noise and loading of the divider by an oscilloscope become significant issues.
    5. Part 4: Studying voltage dividers constructed with combinations of resistors, inductors and capacitors that function as filters. Some additional general properties of dividers are also identified.
    6. Part 5: The use of voltage dividers for measuring internal resistances of sources and loads such as battery resistance and the input resistance of measurement devices like voltmeters and scopes. Also for determining the resistance of resistive sensors like photocells, strain gauges and force sensors.
    7. Part 6: The role of voltage dividers in the operation of transformers.
    8. Part 6.1 Designing circuits by functional blocks.
    9. Part 7: Deriving the transfer functions for inverting and non-inverting op-amp amplifiers using what we know about voltage dividers. Also, voltage dividers where neither end is at zero Volts -- a generalization useful for non-inverting op-amps and Schmitt Triggers.
    10. Part 8: Configuring two voltage dividers into a Wheatstone Bridge circuit. Other uses of dividers as voltage references.
    11. Part 9: How does SPICE work? The material in this video is not required for EI but is useful for anyone who wishes to understand circuit analysis a little more deeply.
    12. Part 10: Transistor and relay switches. The Schmitt Trigger.
    13. Part 11: Digital Logic Circuits & the 555 Timer
    14. Part 12: Diode Rectifiers - Dividing voltage between diodes and resistors.
    15. Part 13: Powering LEDs - Dividing voltage between an LED and a current-limiting resistor.
    16. Part ?: Making high voltage measurements.
    17. Part ?: Oscilloscope Probes
    18. Part ?: Other

Experiment and Project Lectures

These are traditional lectures developed to provide basic background for each assignment. They were originally designed to be watched through from beginning to end (i.e. the entire playlist for each assignment). Of course, it is possible to stop at any point and re-play parts that need a little more time. As you watch the videos and have questions, post the questions on the EI piazza site and you will generally receive an answer within the hour. In recent semesters, the average time for an answer has been about 16 minutes. Another good way to use these videos is to have two windows open on your computer with the PowerPoint slides for the lecture in one window and the video open in the other. Read through the slides for the assignment you are interested in and then go to the videos when you need additional explanation to go with the slide. That way you only watch a subset of the videos.

Experiment 1 -- Signals, Instrumentation, Basic Circuits and Capture/PSpice

  1. Complete Lecture
  2. Playlist
  3. Individual Videos
    1. Part 1: Quick Overview
    2. Part 2: Quick Overview Continued
    3. Part 3: Ohm's Law and Sinusoids
    4. Part 4: Voltage Dividers
    5. Part 5: Impedance
    6. Part 6: Impedance Continued
    7. Part 7: Kirchoff's Laws for Voltage and Current - Conservation Laws for Circuits
    8. Part 8: Analysis of Signals from Voltage Dividers, Especially When the Resistors are Large

Experiment 2 -- Complex Impedance, Steady State Analysis and Filters (Highlights)

  1. Complete Lecture: The videos on Complex Numbers (see above) should be viewed first if your background is limited. The videos on Transfer Functions (also see above) should be viewed either before or after the highlights.
  2. Playlist
  3. Individual Videos
    1. Part 1: What is a transfer function? Voltage divider example. Phasor notation. Complex impedance.
    2. Part 2: Using complex transfer functions. RC circuit example. Filters. Corner frequency.
    3. Part 3: Resonant frequency. Very low & very high frequencies.
    4. Part 4: Equivalent impedance. Transfer functions for more complex circuits.

Experiment 3 -- Inductors and Transformers (Overview)

  1. Complete Lecture: The videos on transformers, inductors, Thevenin equivalents, and coil winding are also for this experiment.
  2. Playlist
  3. Individual Videos
    1. Part 1: General overview and how to calculate inductance.
    2. Part 2: More on calculating inductance and resistance of inductor.
    3. Part 3: Using online calculators, measuring inductance, what transformers look like, transformers in PSpice.
    4. Part 4: Ideal operation of transformer, using PSpice to find the range of frequencies for which the transformer works as it should (very important topic), step-up & step-down transformers.
    5. Part 5: Building a step-down transformer, examples and demos.

Experiment 4 -- Op-Amp Circuits

  1. Complete Lecture:
  2. Playlist:
  3. Individual Videos
    1. Part 1: Introduction to Op-Amps; op-amp chips.
    2. Part 2: More intro; packaging and connections; power for the chip; intrinsic gain (aka open loop gain); saturation.
    3. Part 3: Positive and negative feedback; overview of what we can do with op-amps.
    4. Part 4: PSpice set-up and analysis; inverting and non-inverting amplifier.
    5. Part 5: Op-amp analysis; the Golden Rules of op-amps;
    6. Part 6: An alternate, simple analysis of the inverting op-amp that covers essentially all of the steps in the more detailed analysis shown in the ppt slides. You should still go through the approach in the slides.
    7. Part 7: Summarizing the analysis of the inverting & non-inverting amplifiers; buffer (voltage follower).
    8. Part 8: More on buffer; intro to differentiator and integrator op-amp configurations.
    9. Part 9: Integrators and differentiators.
    10. Part 10: General discussion of integrators and differentiators using phasor notation.
    11. Part 11: More on frequency response of integrators and differentiators (Bode Plot)
    12. Part 12: Difference amplifiers (instrumentation amps); practical characteristics of op-amps.

Experiment 5 -- Harmonic Oscillation

  1. Complete Lecture:
  2. Playlist:
  3. Individual Videos
    1. Part 1: How do we use strain gauges? Wheatstone Bridge.
    2. Part 2: Bridge circuit. PSpice Parameter Sweep. Thevenin Voltage Source.
    3. Part 3: Modeling damped oscillations; harmonic oscillators; spring-mass model; Young's Modulus.
    4. Part 4: Determining the parameters of the harmonic oscillator model for the cantilever beam through measurements of frequency, etc.
    5. Part 5: Harmonic oscillator model of a resonant LC circuit; compare with spring-mass system; examples of cantilever beams.
    6. Part 6: Thevenin voltage source representation of a Wheatstone Bridge.
    7. Part 7: Method for determining Thevenin voltage source; continuation of finding Thevenin voltage source for Wheatstone Bridge.
    8. Part 8: Using the Wheatstone Bridge circuit to measure the strain.
  4. StrainGaugeBridge A simple explanation of why the resistance we measure for one of the strain gauges is significantly smaller than 350 Ohms.

Experiment 6 -- Electronic Switches

  1. Complete Lecture:
  2. Playlist:
  3. Individual Videos
    1. Part 1: Analog vs. Digital Circuits; Transistors as switches; conceptual description of a bi-polar transistor (BJT).
    2. Part 2: Transistors as switches; field effect transistor (FET); pnp & npn transistors; characteristics of transistors.
    3. Part 3: Transistor operating regimes; switch model and diode model of the BJT; using a transistor as a switch; building logic gates with transistors.
    4. Part 4: Comparators; comparator response to noisy inputs.
    5. Part 5: Schmitt Trigger; hysteresis; switching levels; noise immunity; digital chip package.
    6. Part 6: Schmitt Triggers vs inverters; relays (a switch that makes some noise); building a relay-switching circuit.

Experiment 7 -- Digital Logic Devices and the 555-Timer

  1. Complete Lecture:
  2. Playlist:
  3. Individual Videos
    1. Part 1: Intro & Overview, Logic Gates
    2. Part 2: Logic Gates Continued
    3. Part 3: Logic Gates & Flip Flops
    4. Part 4: Flip Flops
    5. Part 5: Flip Flops & Bypass Capacitors
    6. Part 6: Counters
    7. Part 7: Counters Continued, 555 Timer
    8. Part 8: 555 Timer Continued
    9. Part 9: Astable Multivibrator
    10. Part 10: Uses of 555s, Pulse Width and Pulse Position Modulation

Experiment 8 -- Diodes, Phototransistors and LEDs

  1. Complete Lecture: Should also view the video above on Load Lines.
  2. Playlist:
  3. Individual Videos
    1. Part 1: Introduction to diodes; diode package and symbol; half-wave rectifier; i-v characteristics of resistors and diodes.
    2. Part 2: i-v characteristic of ideal and real diodes; reverse breakdown voltage; finite turn-on voltage; the Shockley diode equation; Mobile Studio set-up for i-v characteristic.
    3. Part 3: Use of diodes in rectifiers (half-wave and full-wave); rectifiers with smoothing; using diodes to limit voltages.
    4. Part 4: More on Voltage Limitation, LEDs, Photodiodes, Phototransistors, Zener Diodes

Project 1 -- Instrumented Beakman's Motor

  1. Complete Lecture:
  2. Playlist:
  3. Individual Videos
    1. Motor Design Part 1: A discussion of how to most effectively remove the enamel from the axle to produce the largest force to rotate the coil.
    2. Motor Design Part 2: Discussion Continued
    3. Motor Design Part 3: Discussion Continued
    4. Beakman's Motor Part 1: Intro & Overview of Beakman's Motor project addressing the general purpose, the materials used, teaming.
    5. Beakman's Motor Part 2: Measuring the motor speed. The list of tasks to be completed in this project and some discussion of issues that can affect motor performance.
    6. Beakman's Motor Part 3: The use of springs to improve the motor performance. Project requirements…
    7. Beakman's Motor Part 4: Continuation of discussion of force direction. Discussion of the websites listed on the course webpage.
    8. Beakman's Motor Part 5: More discussion of information available online, especially videos that can be found on YouTube.…

Project 2 -- Cantilever Beam

Project 3 -- Switch Debouncer

Project 4 -- Optical Communications Link

  1. Complete Lecture:
  2. Playlist:
  3. Individual Videos
    1. Optical Transmitter-Receiver Part 1: Intro & Overview
    2. Optical Transmitter-Receiver Part 2: Block Diagram - Functionality, Transmitter
    3. Optical Transmitter-Receiver Part 3: Receiver
    4. Optical Transmitter-Receiver Part 4: Importance of Measuring Both Input and Output of Each Stage of a Circuit
    5. Optical Transmitter-Receiver Part 5: Testing Ideas & Extra Credit

Quiz Review

These videos were prepared as review lectures to be watched completely to prepare for each quiz (There used to be 4 quizzes in EI, now there are 3.) However, they are also very good solved problem examples for homework questions. The use an example from these videos, look for the corresponding topic, which may be addressed in more than one video.

  1. Quiz 1
    1. Complete Lecture
    2. Playlist
    3. Individual Videos:
      1. Part 1: Simplifying combinations of resistors where some are in series and some are in parallel. Ohm's Law. Voltage Divider.
      2. Part 2: Completing the problem from Part 1. The second problem addresses filters. There is a suggestion to take a quick look at the circuits before analyzing them which, in this case, makes them simpler to understand.
      3. Part 3: Continuation of Problem 2 on Filters. Simplification of filters at low and high frequencies. Redrawing circuits to understand them better. Simplifying circuits at resonance.
      4. Part 4: Completion of Problem 2 on Filters. Applying simplified filter transfer to estimate the output of a filter at a given frequency. Problem 3 addresses transfer functions. Applying the voltage divider formula and then simplifying complex transfer functions. Transfer functions at low (not zero) and high (not infinity) frequencies.
      5. Part 5: More on Problem 3 on transfer functions. Evaluating transfer function for specific component values. Magnitude of transfer function. Frequencies when transfer function goes to zero. Problem 4 on Transformers. Ideal transformers. Impedance transformation.
      6. Part 6: Continuation of Problem 4 on Transformers. Calculation of inductance from ideal formulas. RLC circuit resonance. Identifying filter type.
      7. Part 7: Final part of Problem 4 on changing where output is measured. Problem 5 based on PSpice Analysis. Questions address setting up and running the analysis. identifying information in output plots. Comparing results from AC sweep and transient analyses.
      8. Part 8: Continuation of Problem 5 on using PSpice. Next, setting up the measurements using Mobile Studio. Characteristics to look for in plots.
  2. Quiz 2
    1. Complete Lecture
    2. Playlist
    3. Individual Videos:
      1. Part 1: Review of basic math operations for sine, cosine, exponential functions.
      2. Part 2: Review of basic math of sine, cosine, exponential functions.
      3. Part 3: Using Simulink to demonstrate basic concepts in Experiments 4 & 5
      4. Part 4: Using Simulink to demonstrate basic concepts in Experiments 4 & 5
      5. Part 5: Using PSpice to review basic concepts of RLC circuits.
      6. Part 6: Using PSpice to review basic concepts of RLC circuits.
      7. Part 7: Using PSpice to review basic concepts of RLC circuits.
      8. Part 8: Reviewing op-amp analysis.
      9. Part 9: Reviewing op-amp analysis.
      10. Part 10: Finding period, frequency, amplitude, phase, decay constant, etc. of signal.
      11. Part 11: A bit more on the math question. Thevenin voltage and resistance determination.
      12. Part 12: Thevenin source determination
      13. Part 13: Op-amp applications.
      14. Part 14: Op-amp applications, op-amp analysis, integrators and differentiators
      15. Part 15: Op-amp analysis, transfer function
      16. Part 16: Op-amp analysis, transfer function
      17. Part 17: Op-amp analysis, Bode Plots
      18. Part 18: Op-amp analysis, Bode Plot
      19. Part 19: A very general intro to finding Thevenin voltage representations
      20. Part 20: Finding a Thevenin equivalent source -- Example
  3. Quiz 3
    1. Complete Lecture
    2. Playlist
    3. Individual Videos:
      1. Part 1: Overview
      2. Part 2: Astable Multivibrator (555)
      3. Part 3: 555 Continued (Reminder to always draw simplified circuits)
      4. Part 4: Combinational Logic Circuits
      5. Part 5: Sequential Logic Circuits
      6. Part 6: Sequential Logic Continued
      7. Part 7: Transistor Switch Relay Circuit
      8. Part 8: Switching Continued
      9. Part 9: Comparators & Schmitt Triggers
  4. Quiz 4
    1. Complete Lecture
    2. Playlist
    3. Individual Videos:
      1. Part 1: Overview
      2. Part 2: Diode Rectifier Circuits
      3. Part 3: Rectifiers Continued
      4. Part 4: Diode Limiter Circuits
      5. Part 5: Zener Diode Circuits
      6. Part 6: Zeners Continued
      7. Part 7: LEDs & Phototransistor Circuits
      8. Part 8: LEDs & Phototransistors Continued
      9. Part 9: Signal Modulation & Functionality
      10. Part 10: Final Comment on Reading Entire Quiz Before Starting
      11. Rectifier with Smoothing Part 1: Self Explanatory
      12. Rectifier with Smoothing Part 2: Self Explanatory