Agilent Technologies 2000 X-Series, Руководство пользователя

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50 Agilent InfiniiVision 2000 X-Series Oscilloscopes User's Guide
2
Horizontal Controls
XY Time Mode
The XY time mode converts the oscilloscope from a volts- versus- time
display to a volts- versus- volts display using two input channels. Channel 1
is the X- axis input, channel 2 is the Y- axis input. You can use various
transducers so the display could show strain versus displacement, flow
versus pressure, volts versus current, or voltage versus frequency.
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):
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