Time Interval Measurements - PeakTech 2035 Bedienungsanleitung

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.
3. Use the vertical POSITION control (4) or (7) to position the trace to the central horizontal
gratitude line passes through the points on the waveform between which you want to make the
measurement.
4. Use the Horizontal POSITION control (10) to set the left-most measurement point on a nearly
vertical gratitude line.
5. Count the number of horizontal gratitude divisions between the Step 4 gratitude line and the
second measurement point. Measure to a tenth of a major division. Note that each minor division
on the central horizontal gratitude line is 0.2 major division.
6. To determine the time interval between the two measurement point, multiply the number of
horizontal divisions counted is Step 5 by the setting of the TIME/DIV switch. If the X10 MAG (11)
is X 10 (x10 magnification), be certain to divide the TIME/DIV switch setting by 10.
Period, Pulse, Width and Duty Cycle
The basic technique described in the preceeding paragraph can be use to determine pulse parameters
such as period, pulse width, duty cycle, etc.
The period of a pulse or any other waveform is the time it takes for one full cycle of the signal. In Figure 2-
7, the distance between points (A) and (C) represent one cycle; the time interval of this distance is the
period. The time scale for the CRT display of figure 2-7 A is 10 ms/div, so the period is 70 milliseconds in
this example.
Pulse width is the distance between points (A) and (B). In our example it is conveniently 1.5 divisions, so
the pulse width is 15 milliseconds. However, 1.5 division is a rather small distance for accurate
measurements, so it is advisable to use a faster sweep speed for this particular measurement. Increasing
the sweep speed to 2 ms/div as in Figure 2-7 gives a large display, allowing more accurate measurement.
If it is seen small with the TIME/DIV switch you may measure X 10 is expanded condition by putting X10
MAG switch to X10 MAG. The duty cycle may be calculated by knowing pulse breadth and cycle.
The distance between points (B) and (C) is then called offtime. This can be measured in the same
manner as pulse width.
When pulse width and period are known, duty cycle can be calculated. Duty cycle is the percentage of the
period (or total of on and off times) represented by the pulse width (on time).
Duty cycle (%) =
Duty cycle of example =
PW (100) = A -> B (100)
Period A-> C
15 ms x 100
= 21,4 %
70 ms
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