Kenwood CS-1100 Instruction Manual page 22

P H A S E DIFFERENCE MEASUREMENTS
This procedure is useful in measuring the phase difference
of signals of the same frequency.
Procedure:
1. Apply the two signals to the channel 1 and channel 2 IN-
PUT jacks, setting the vertical MODE switch to either
CHOP or A L T mode.
2. Set the SOURCE to the signal which is leading in phase
and use the VOLTS/DIV to adjust the signals such that
they are equal in amplitude. Adjust the other controls for
a normal display.
3. Use the SWEEP TIME/DIV and A VARIABLE controls to
adjust the display such that one cycle of the signals oc-
cupies 8 divisions of horizontal display.
Use the r POSITION control to bring the signals in the
center of the screen.
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 two waveforms.
Using the formula:
Phase difference = Horizontal distance (div) x 45°/div
Reference signal
Comparison
signal
[EXAMPLE]
For the example, the horizontal distance is 1.7 divisions.
(See Fig. 22)
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 SWEEP TIME/DIV may be changed
and magnified without touching the VARIABLE control and
if necessary the trigger level can be readjusted.
2 2
1 cycle
Phase difference
Fig. 22
For this type of operation, the relationship of one division to
4 5 ° no longer holds. Phase difference is defined by the for-
mula as follows.
Phase difference = Horizontal distance of new sweep range
( d i v ) x 4 5 ° / d i v
New SWEEP TIME/DIV setting
x
Original SWEEP TIME/DIV setting
Another simple method of obtaining more accuracy quickly
is to simply use x 10 MAG for a scale of 4.5°/div.
RELATIVE MEASUREMENT
If the frequency and amplitude of some reference signal are
known, an unknown signal may be measured for level and
frequency without use of the VOLTS/DIV or SWEEP
TIME/DIV for calibration.
The measurement is made in units relative to the reference
signal.
* Vertical Sensitivity
Setting the relative vertical sensitivity using a reference
signal.
Procedure:
1. Apply the reference signal to the INPUT jack and adjust
the display for a normal waveform display.
Adjust the VOLTS/DIV and VARIABLE controls so that
the signal coincides with the C R T face's graduation
lines. After adjusting, be sure not to disturb the setting
of the VARIABLE control.
Phase difference
One cycle adjusted to occupy 8 div.
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