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Using the formula:
Sweep coefficient
Using the formula:
Period of unknown signal = Width of 1 cycle (div) x sweep
coefficient x SWEEP TIME/DIV setting
Reference signal
Adjusted reference signal
Unknown signal
Fig. 43
[EXAMPLE]
SWEEP TIME/DIV is 0.1 ms and apply 1.75 kHz reference
signal. Adjust the VARIABLE so that the distance of one cy-
cle is 5 divisions.
,
Substituting the given value:
1.75 (kHz)~1
Horizontal coefficient = ————-——————__
5 (div) x 0.1 (ms/div)
=1.143
Then, SWEEP TIME/DIV is 0.2 ms/div and horizontal am-
plitude is 7 divisions. (See Fig. 43)
Substituting the given value:
Pulse width= 7 (div) x 1.143 x 0.2 (ms/div) = 1.6 ms
13. PULSE JITTER MEASUREMENT
1. Apply the signal to the INPUT jack and set the vertical
MODE to the channel to be used.
Use the VOLTS/DIV to adjust for an easy to observe
waveform display. Special care should be taken to ad-
just the trigger group of controls for a stable display.
Set the SWEEP VARIABLE to CAL position.
2. Set the HORIZ MODE switch to ALT, and depress the
HOLD OFF control.
Adjust the DELAY TIME POSITION for intensified display
of the waveform to be measured.
3. Using the B SWEEP TIME/DIV adjust the display for in-
tensificaion of the entire jitter area of the waveform.
4. Set the HORIZ MODE to B.
Measure the width of the jitter area.
The jitter time is this width in division multiplied by the
setting of the
B SWEEP TIME/DIV control.
Using the formula:
Pulse jitter = Jitter width (div) x B SWEEP TIME/DIV
setting
[EXAMPLE]
The example shows a case in which the jitter width was
measured at 1.6 divisions wide with the B SWEEP TIME/DIV
set at 0.2 ps. (See Fig. 44)
Substituting the given value:
Pulse jitter = 1.6 (div) x 0.2 (zs) =0.32 us
100
90
10
0%
Pulse jitter
Fig. 44
31
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