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2. T h e S w e e p (horizontal) calibration coefficient is then the
period of the reference signal divided by the product of
the number of divisions used in step 1 for setup of the
reference and the setting of the S W E E P
control.
Using the formula:
S w e e p coefficient
Period of the reference signal (sec)
horizontal width (div) x S W E E P T I M E / D I V setting
3. Remove the reference signal and input the unknown sig-
nal, adjusting the S W E E P T I M E / D I V control for easy ob-
servation.
Measure the width of one cycle in divisions and use the
following relationship to calculate the actual period.
Using the formula:
Period of unknown signal = Width of 1 cycle (div) x s w e e p
coefficient x S W E E P T I M E / D I V setting
Adjusted reference signal
Reference signal
Fig. 4 2
Unknown signal
Fig. 4 3
[EXAMPLE]
S W E E P T I M E / D I V is 0.1 ms and apply 1.75 kHz reference
signal. Adjust the V A R I A B L E so that the distance of one cy-
T I M E / D I V
cle is 5 divisions.
Substituting the given value:
Horizontal coefficient = — ^ - 7 5 (kHz)
T h e n , S W E E P T I M E / D I V is 0 . 2 ms/div and horizontal am-
plitude is 7 divisions. (See Fig. 4 3 )
Substituting the given value:
Pulse width = 7 (div) x 1 . 1 4 3 x 0 . 2 (ms/div) 1.6 m s
1 3 . P U L S E J I T T E R M E A S U R E M E N T
1 . Apply the signal to the INPUT jack and set the vertical
MODE to the channel to be used.
Use the V O L T S / D I V to adjust for an easy to observe
w a v e f o r m display. Special care should be taken to ad-
just the trigger group of controls for a stable display.
Set the S W E E P V A R I A B L E to C A L position.
2. S e t the HORIZ MODE s w i t c h to A L T , and depress the
HOLD O F F control.
Adjust the D E L A Y T I M E POSITION for intensified display
of the w a v e f o r m to be measured.
3 . Using the B S W E E P T I M E / D I V adjust the display for in-
tensificaion of the entire jitter area of the w a v e f o r m .
4 . S e t the HORIZ M O D E to B.
Measure the width of the jitter area.
The jitter time is this width in division multiplied by the
setting of the B S W E E P T I M E / D I V control.
Using the formula:
Pulse jitter = Jitter width (div) x B S W E E P T I M E / D I V setting
[EXAMPLE]
The example s h o w s a c a s e in w h i c h the jitter width w a s
measured at 1.6 divisions wide with the B S W E E P TIME/DIV
set at 0 . 2 ^ s . ( S e e Fig. 4 4 )
Substituting the given value:
Pulse jitter = 1.6 (div) x 0 . 2 (^s) = 0 . 3 2 jis
5 (div) x 0.1 (ms/div)
= 1.143
Puise jitter
Fig. 4 4
3 1
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