Tektronix 2335, Instruction Manual

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5. If the tw o signals are o f opposite polarity, press in
the CH 2 IN VE R T push button to invert the Channel 2
display.
6. Set both V O LT S /D IV switches and both VAR
controls so the displays are equal in amplitude.
graticule line (50% o f rise tim e) and calculate the phase
difference using the following form ula:
Phase
Difference
horizontal
difference
(divisions)
horizontal
graticule
calibration
(deg/div)
7. Adjust the A TRIGGER LEVEL control fo r a stable
display.
EXAMPLE: The horizontal difference is 0.6 division
w ith a graticule calibration o f 45° per division as shown
in Figure 19.
8. Set the A SEC/DIV switch to a sweep speed which
displays about one fu ll cycle of the waveforms.
9. Position the displays and adjust the TIME (PULL)
VAR control so that one reference-signal cycle occupies
exactly 8 horizontal graticule divisions at the 50% rise-time
points (see Figure 19). Each division o f the graticule now
represents 45° o f the cycle (360° 4- 8 divisions), and the
horizontal graticule calibration can be stated as 45° per
division.
10. Measure the horizontal difference between corre­
sponding points on the waveforms at a common horizontal
Substituting the given values into the phase difference
form ula:
Phase Difference = 0.6 div x 45° /div = 27°
More accurate phase measurements can be made by
using the X I 0 MAG function to increase the sweep rate
w itho ut changing the SEC/DIV TIM E (PULL) VAR control
setting.
EXAMPLE: If the sweep rate were increased 10 times
w ith the magnifier (X10 MAG push button in), the
magnified horizontal graticule calibration would be
4 5 ° /division divided by 10 (or 4 .5 ° /division). Figure 20
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2335 Operators