Aegis OSC-9200, Руководство пользователя

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Horizontal Format
Press Acquire on the front panel; then press the XY F key to choose XY (On) or YT (Off ) mode. The
default setup is YT .
YT
This is the normal viewing mode. In this mode, signal events occurring before the trigger are plotted
to the left of the trigger point and signal events after the trigger plotted to the right of the trigger point.
XY
XY mode changes the display from volts vs time to a volts vs volts display, using signal from both
channels. Channel 1 amplitude is plotted on the X- axis and Channel 2 amplitude is plotted on the Y-
axis. The two channels will be turned on or off together.
You can use XY mode to compare frequency and phase relationships between two signals. XY mode
can also be used with transducers to display strain versus displacement, flow versus pressure, volts
versus current, or voltage versus frequency.
The phase deviation between two signals with the same frequency can be easily measured by the
Lissajous method. The figure below is a schematic diagram of the phase deviation:
The phase deviation angle θ can be obtained using sin θ = A/B or C/D (where A, B, C, and D are as
shown in the figure above): θ = ± arcsin (A/B) or ± arcsin (C/D)
If the principal axis of the ellipse is within quadrant I and III, the phase deviation angle obtained should
be within quadrants I and IV, namely within (0 to
π /2) or (3 π /2 to 2 π ). If the principal axis of the is
within quadrant II and IV, the phase deviation angle will be within quadrant II and III, namely within
(
π /2 to π ) or ( π to 3 π /2).
XY mode can be used to measure the phase shift that occurs when the signal under test passes
through a circuit network. Connect the oscilloscope to the circuit to monitor the input and output
signals of the circuit.