Tektronix 5110, Инструкция по эксплуатации

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Operating lnstructions-5110
Fig. 1-5. Measuring time duration (period) between points on
a
waveform.
3. Adjust the vertical Position control to move the
points between which the time measurement is made to
the center horizontal line. Adjust the horizontal Position
control to center the time-measurement points within the
center eight divisions of the graticule.
4. Measure the horizontal distance between the time
measurement points. Be sure the variable Seconds/Div
control is in the Cal position.
5. Multiply the distance measured in step 4 by the
setting of the Seconds/Div switch.
EXAMPLE: Assume that the horizontal distance
between the time-measurement points is five divisionsand
the Seconds/Div switch is set to .1 ms. Using the formula:
2. Take the reciprocal of the period to determine the
frequency.
EXAMPLE: The frequency of the signal shown in Fig. 1-
5, which has a period of 0.5 millisecond is:
Frequency = —V-r = 73-=^----- = 2 kilohertz
M 1 period 0.5 ms
1. Measure the period of one cycle of the waveform as
described in the previous application.
Risetime Measurement
Risetime measurements employ basically the same
techniques as the time-period measurements. The main
difference is the points between which the measurement is
made. The following procedure gives the basic method of
measuring risetime between the 10% and 90% points of the
waveform.
1. Connect the signal to the input connector.
2. Set the Volts/Div switch and variable Volts/Div
control to produce a display exactly five divisions in
amplitude.
3. Center the display about the center horizontal line
with the vertical Position control.
4. Set the time-base triggering controls to obtain a
stable display. Set the Seconds/Div switch to the fastest
sweep rate that will display less than eight divisions
between the 10% and 90% points on the waveform (see Fig.
1-6).
horizontal Sec/Div
Period — distance x switch (5) (0.1 ms) = 0.5 ms
(divisions) setting
The period is 0.5 millisecond.
Determining Frequency
The time measurement technique can also be used to
determine the frequency of a signal. The frequency of a
periodically recurrent signal is the reciprocal of the time
duration (period) of one cycle. Use the following
procedure:
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