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- Adjust 9 0 % point to the center
and measure D
Rise time
Fig. 26
[EXAMPLE]
For the example, the measured D
is 1.4 divisions. If S W E E P T I M E / D I V is 2 (jis/div) w e use
the following relationship. (See Fig. 2 6 )
Substituting the given value:
Risetime = ( 1 . 6 + 1 . 4 ) ( d i v ) x 2 (/xs/div) = 6 ^ s
(2) Cursor measurement
1 . In the same w a y as the ordinary measurement, adjust
the waveform height displayed on the screen to 5 divi-
sions, and align the bottom and top of the waveform
with 0 % and 1 0 0 % respectively using the • POSITION
switches.
2 . Set the cursor mode to AT.
A R E F cursor to
3 . Adjust
the
waveform and the 1 0 % division of the scale, and the
A cursor to the crossing of the waveform and the
9 0 % division.
4 . Measured value is displayed in the upper right part on
the screen posterior to AT.
24
.
2
Adjust 1 0 % point
to the center and
measure Dj.
is 1.6 divisions while D
t
the
crossing of
the
Measured value
cursor
, REF cursor
Fig. 27
9 .
PHASE DIFFERENCE M E A S U R E M E N T S
(1) Ordinary measurement
Phase difference between t w o sine w a v e s of the same fre-
quency, etc. can be measured as follows:
Procedure:
1 . Apply the t w o signals to the C H 1 and C H 2 INPUT jacks,
setting the vertical MODE to either CHOP or A L T mode.
2. Set the controls to obtain normal s w e e p . Set the
S O U R C E switch to select the signal which is leading in
phase (reference signal), and adjust the V O L T S / D I V and
vertical V A R I A B L E controls such that the t w o signals
are equal in amplitude.
3 . Use the S W E E P TIME/DIV and S W E E P V A R I A B L E to ad-
just the display such that one cycle of the signals oc-
cupies 8 divisions of horizontal display.
Operate • POSITION to shift the t w o signals on the
center of the scale.
Having set up the display as above, one division now
represents 4 5 ° in phase.
4 . Measure the horizontal distance between corresponding
points on the t w o waveforms.
2
Using the formula:
Phase difference = Horizontal distance (div) x 4 5 ° / d i v
Reference signal
Comparison
signal
[EXAMPLE]
For the example, the horizontal distance is 1.7 divisions.
(See Fig. 2 8 )
Substituting the given value:
The phase difference = 1.7 (div) x 4 5 ° / d i v = 7 6 . 5 °
The above setup allows 4 5 ° per division but if more ac-
curacy is required the S W E E P T I M E / D I V may be changed
and magnified without touching the V A R I A B L E control and
if necessary the trigger level can be readjusted.
In this case, the phase difference can be obtained from the
S W E E P T I M E / D I V setting for 8 divisions/cycle and the new
S W E E P T I M E / D I V setting changed for higher accuracy, by
useing the following formula.
1 cycle
Phase difference
Fig. 28
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