Keysight Technologies DSO-X 2014A, Руководство пользователя

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52 Keysight InfiniiVision 2000 X-Series Oscilloscopes User's Guide
2
Horizontal Controls
Example This exercise shows a common use of the XY display mode by measuring the
phase difference between two signals of the same frequency with the Lissajous
method.
1 Connect a sine wave signal to channel 1, and a sine wave signal of the same
frequency but out of phase to channel 2.
2 Press the [AutoScale] key, press the [Horiz] key; then, press Time Mode and select
"XY".
3 Center the signal on the display with the channel 1 and 2 position ( ) knobs.
Use the channel 1 and 2 volts/div knobs and the channel 1 and 2 Fine softkeys
to expand the signal for convenient viewing.
The phase difference angle ( θ ) can be calculated using the following formula
(assuming the amplitude is the same on both channels):
4 Press the [Cursors] key.
5 Set the Y2 cursor to the top of the signal, and set Y1 to the bottom of the
signal.
Note the Δ Y value at the bottom of the display. In this example, we are using
the Y cursors, but you could have used the X cursors instead.
Figure 3 XY time mode signals, centered on display
sin θ =
A
B
or
C
D
A
B D
C
Signal must
be centered in
“ X”
Measuring
phase difference
Signals 90 degrees
out of phase
Signals
in phase