8. If the phase difference is less than 50° (one major division), set the x10 MAG switch is x10, and use
the Horizontal POSITION control (if needed) to position the measurement area back on screen. With
10 x magnification, each major division is 5° and each minor division is 1°.
Lissajous Pattern Method
This method is used primarily with sine waves. Measurements are possible at frequencies up to 500 kHz, the
bandwith of the horizontal amplifier. However, for maximum accuracy, measurements of small phase
difference should be limited below 50 kHz.
To measure phase difference by the Lissajous pattern method, proceed as follows:
1. Rotate the TIME/DIV switch fully clockwise to its X-Y position.
Caution: Reduce the trace intensity least the undeflected spot damage the CRT phosphor.
2. To measure by setting INV to NORM and X5 MAG to X1.
3. Connect one signal to the CH 1 or X IN connector (24), and the other sight to the CH 2 or Y IN
connector (22).
4. Center the trace vertically with the CH2 Vertical POSITION control (7) and adjust the CH 2
VOLTS/DIV switch (23) and VARIABLE control (20) for a trace height of exactly 6 divisions (the 100
% and 0 % gratitude linestangent to the trace).
5. Adjust the CH 1 VOLTS/DIV Switch (26) for the largest-possible on-screen display.
(a) Phase Angle Calculation
(b) Lissajous-Patterns of various Phase Angles
Fig. 2-10: Lissajous Method of Phase Measurement
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