This lab was an introduction to the oscilloscope which is a tool used to analyze time-varying signals. The scope operates by deflecting an electron beam onto a special phosphor-coated screen which lights up when the beam hits it. Controls allow you to vary the voltage and time scale so that the input signal can be displayed as desired. In our case we used a function generator to generate the 4 different signals below which could then be analyzed. The first 3 were known sinusoid and squarewave signals with/without DC offsetting and the final was an unknown mystery signal. This mystery signal appeared as a modified squarewave with a slight decay at the peaks.
Ex 1: | 5 kHz 5V Sinusoid | |
Period | 200 microsec | |
Pk-Pk ampl | 10 V | |
Zero-Pk ampl | 5 V | |
RMS | 3.53 V | |
DMM readings: | ||
VDC | 0 V | |
VAC | 3.3 V | |
Ex 2: | 5 kHz Sinusoid w 2.5 V DC Offset | |
DMM readings: | ||
VDC | 2.51 V | |
VAC | 3.32 V | |
Ex 3: | 5 kHz Squarewave w 2.5 V DC Offset | |
DMM readings: | ||
VDC | 2.51 V | |
VAC | 5.25 V | |
Calculated RMS | 3.34 V | |
Ex 4: | Mystery signal | |
DC voltage | 2.5 V | |
Frequency | 100 Hz | |
Pk-Pk Amp | .4 V |