Review and Practice

Self-Check

• In this activity you:
  • Probed,  measured, and graphed voltage with an oscilloscope.
  • Examined the appearance of the duty cycle on the voltage vs time graph.
  • Used the Time/Div control to view the voltage signal in more detail.
• Were you able to manipulate the duty cycle through the script?
• Could you see the relationship between the LEDs supply voltage and time?

Questions

1. What are oscilloscopes used for?
2. What does an oscilloscope do?
3. What does it mean to have a falling trigger event?
4. Describe a rising edge.
5. Where on the graph will you find the high signal represented?
    

Exercises

1. How do you change the duty cycle from 50% to 75%?
2. What is the purpose of sleep(1) in the oscilloscope script?
3. In order to more closely inspect each on/off signal on the graph, you can make adjustments to which setting on the CYBERscope?
4. What function sends data to the CYBERscope so that it can be displayed on the graph?
    

Project

Change the resistor in the green LED circuit to a 1 kΩ resistor (brown-black-red-gold). What changes do you observe in the graph? (Make sure to switch the resistor back.)