Fig. 2.5: Peak-To-Peak Voltage Measurement Fig. 2.6: Instantaneous Voltage Measurements
Instantaneous Voltages:
To measure instantaneous voltage, proceed as follows:
1.
Set up the scope for the vertical mode desired per the instructions in 2.3 BASIC OPERATING
PROCEDURES.
2.
Adjust the TIME/DIV switch (15) for one complete cycle of waveform and set the VOLTS/DIV
switch for a trace amplitude of 4 to 6 divisions (see Figure 2.6)
3.
Flip the AC/GND/DC switch (25) or (21) to GND.
4.
Use the appropriate Vertical POSITION control (4) or (7) to set the baseline on the central
horizontal gratitude line. However, if you know the signal voltage is wholly positive, use the
bottommost gratitude line. If you know the signal voltage is wholly negative, use the uppermost
gratitude line.
5.
Flip the AC/GND/DC switch to DC. The polarity of all points above the ground reference line is
positive; all points below the ground-reference line are negative.
Caution:
Make certain the waveform is not riding on a high-amplitude DC voltage before flipping the
AC/GND/DC
switch.
6.
Use the horizontal POSITION control (10) to position any point of interest on the central vertical
gratitude line. This line has additional calibration marks equal to 0.2 major division each. The voltage
relative to ground at any point selected is equal to the number of divisions from that point to the
ground reference line multiplied by the VOLTS/DIV setting. In the example used for figure 2-6, the
voltage for a 0.5 V/div scale is 2.5 V (5.0 div x 5 V).
7.
If x 5 vertical magnification is used, divide the step 6 voltage by 5. However, if 10 x attenuator probes
are used, multiply the voltage by 10.
2.3.2
Time Interval Measurements
The second major measurement function of the triggered-sweep oscilloscope is the measurement of time
interval. This is possible because the calibrated time base results in each division of the CRT screen
representing a known time interval.
Basic Technique
The basic technique for measuring time interval is described in the following steps. This same technique
applies to the more specific procedures and variations that follow:
1.
Set up scope as described in 2.3.2 Single-trace operation.
2.
To settle Time/Div (15) larger as much as possible so that it may appear on the screen.
To place VAR switch (13) at CAL. Please be careful as the measured value may be incorrect if you
do not follow this instructions.
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