5-13
Making Measurements
To use the XY horizontal mode
To use the XY horizontal mode
The XY horizontal mode converts the oscillo scope 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 t h e d is p l a y c o u l d s h o w s tr a i n ve r s u s d i s p la c e m en t , f lo w v e rs u s p re s s u r e, v o l ts
vers us cu rre nt , o r v olt ag e v ers us fr eq uen cy. Th is exe rc is e sh ow s a co mmo n u se
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.
2Press the
Autoscale key, press the Main/Delayed key, then press the XY
softkey.
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 and2
Vernier softkeys to expand the signal for convenient viewing.
The phase difference angle (θ) can be calculat ed using the following formula
(assuming the amplitude is the same on both channels):
Example of centering a signal on the display
θsin A
B
--- or C
D
----
=
AB
D
C
Signal must
be centered
in X