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Adjust 9 0 % point to the center
and measure D
Rise time
Fig. 45
[EXAMPLE]
For the example, the measured Dj is 1.6 divisions while D
is 1.4 divisions. If SWEEP TIME/DIV is 2 /is/div we use the
following relationship. (See Fig. 45)
Substituting the given value:
Risetime = (1.6+1.4) (div) x 2 (/is/div) = 6 /xs
(2) Cursor measurement
1. In the same way 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 100% respectively using the I POSITION
switches.
2. Set the cursor mode to AT.
3. Adjust the A REF cursor to the crossing of the
waveform and the 10% division of the scale, and the
A cursor to the crossing of the waveform and the
90% division.
4. Measured value is displayed in the upper right part on
the screen posterior to AT.
.
2
Adjust 1 0 % point
to the center and
measure D
.
t
Measured value
cursor
R E F cursor
Fig. 46
9. PHASE DIFFERENCE MEASUREMENTS
(1) Ordinary measurement
Phase difference between two sine waves of the same fre-
quency, etc. can be measured as follows:
Procedure:
1. Apply the two signals to the CH1 and CH2 INPUT jacks,
setting the vertical MODE to either CHOP or ALT mode.
2. Set the controls to obtain normal sweep. Set the
SOURCE switch to select the signal which is leading in
phase (reference signal), and adjust the VOLTS/DIV and
vertical VARIABLE controls such that the two signals
are equal in amplitude.
3. Use the SWEEP TIME/DIV and SWEEP VARIABLE to ad-
just the display such that one cycle of the signals oc-
cupies 8 divisions of horizontal display.
Operate • POSITION to shift the two signals on the
center of the scale.
Having set up the display as above, one division now
represents 45° in phase.
4. Measure the horizontal distance between corresponding
points on the two waveforms.
2
Using the formula:
Phase difference = Horizontal distance (div) x45°/div
-Reference signal
Comparison
signal
[EXAMPLE]
For the example, the horizontal distance is 1.7 divisions.
(See Fig. 47)
Substituting the given value:
The phase difference = 1.7 (div)x45°/div = 76.5°
The above setup allows 45° per division but if more ac-
curacy is required the SWEEP TIME/DIV may be changed
and magnified without touching the VARIABLE control and
if necessary the trigger level can be readjusted.
In this case, the phase difference can be obtained from the
SWEEP TIME/DIV setting for 8 divisions/cycle and the new
SWEEP TIME/DIV setting changed for higher accuracy, by
useing the following formula.
1 c y c l e
Phase difference
Fig. 47
29
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