OBJECTIVES
After performing this experiment, you will be able to:
1. Measure the period and frequency of a sine wave using an oscilloscope.
2. Measure across ungrounded components using the difference function of an oscilloscope.
EVALUATION AND REVIEW QUESTIONS
1. (a) Compare the computed and measured periods for the sine waves in Table 1. Calculate the percent difference for each row of the table.
Table 1-
|
Signal Generator Dial Frequency
|
Computed Period
|
Oscilloscope SEC/DIV
|
Number of Division
|
Measured Period
|
|
1.25 kHz
|
0.8 ms
|
0.1 ms/div
|
8.0 div
|
0.8 ms
|
|
1.90 kHz
|
|
|
|
|
|
24.5 kHz
|
|
|
|
|
|
83.0 kHz
|
|
|
|
|
|
600.0 kHz
|
|
|
|
|
(b) What measurement errors account for the percent differences?
2. Using the measured voltages in Table 2, show that Kirchhoff's voltage law is satisfied.
Table 2-
|
|
Signal Gen. Voltage
|
Voltage across R1
|
Voltage across R2
|
|
Measured
|
|
|
|
|
Computed
|
1.0 Vpp
|
|
|
3. An oscilloscope display shows one complete cycle of a sine wave in 6.3 divisions. The SEMI control is set to 20 ms/div.
(a) What is the period?_________
(b) What is the frequency?____________
4. You wish to display a 10 kHz sine wave on the oscilloscope. What setting of the SEC/DIV cowl will show one complete cycle in 10 divisions?
5. Explain how to measure the voltage across an ungrounded component.