Here are my thoughts on the fourth week's material, etc.

• This week's material is sampling of signals, including the Nyquist limit.
• Sinusoidal signal parameters are the focus - Amplitude, frequency (including angular frequency - "omega") and phase.
• But, the labs get the students to think about limitations that are caused by instrument sampling.
• The concept of sampling is something that I have just begun to emphasize (Spring 2008).  Since these students are generally
• Labs are designed to show the effects of sampling.
• The labs here let students get acquainted with an oscilloscope.  They are probably too short.  And, in this year's redesign of the course I am going to change the labs and move the tachometer experiment to this point.  See below.  Anyhow, those two labs go together and make a good pair.
• The tachometer lab produces a "starry night" display with data that connot be used easily in an analysis program.  Students have to do "by-hand" analysis to get the time constant(s).
• This lab also serves to reinforce the material on time constants.
• In-Class exercises
• I have one or two, but I need to develop more.
• Class Notes - Good so far, but I need a lot more.
• Some things to think about.
• The first part of the lab uses a simulation that I have written.  Works OK
• The second part of the lab uses an AC tachometer attached to a DC motor.  Students can examine the up and down transients which are almost time-constant type behavior.
• Sensors encountered to this point in the course.
• Thermocouples
• LM35s - giving two examples of sensors with voltage outputs
• Thermistor - giving an example of a sensor with a resistance change.
• AC Tachometer
• Thoughts about where this is at this point.
• This segment still needs work.  In prior years I had used a rectifying circuit to try and get a good signal from the AC tach.  Since they are all non-EEs that seemed to be lost on them, and, after some thought I decided to go with more material about sampling effects, and what Mr. Nyquist had to say about sampling rates.  (See the note in the ABET notebook on Sampling.  There's also a simulator on-line.)  Right now this is a little skimpy, but getting better, and seems to be a better topic here than the rectification material.
• The material on sampling rates is surely more important to them, and it ties in better with the things we do when we take lab data on vibrating systems and FFT that data later in the course.  At that point sampling, number of data points, etc. gets to be important.
• And, speaking of data, I have to get some stadium vibration data from Kelly Salyard in CE.  She apparently has lots of that if I can get her to let loose of some of it.