Agilent Technologies DSO-X 4022A, User Manual

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82 Agilent InfiniiVision 4000 X-Series Oscilloscopes User's Guide
3
Vertical Controls
The offset voltage value represents the voltage difference between the
vertical center of the display and the ground level ( ) icon. It also
represents the voltage at the vertical center of the display if vertical
expansion is set to expand about ground (see
"To choose "expand about"
center or ground" on page 335).
To specify channel coupling
Coupling changes the channel's input coupling to either AC (alternating
current) or
DC
(direct current).
1 Press the desired channel key.
2 In the Channel Menu, press the Coupling softkey to select the input
channel coupling:
•
DC
— DC coupling is useful for viewing waveforms as low as 0 Hz
that do not have large DC offsets.
• AC — AC coupling is useful for viewing waveforms with large DC
offsets.
When AC coupling is chosen, you cannot select 50
Ω
mode. This is
done to prevent damage to the oscilloscope.
AC coupling places a 10 Hz high- pass filter in series with the input
waveform that removes any DC offset voltage from the waveform.
Note that Channel Coupling is independent of Trigger Coupling. To change
trigger coupling see
"To select the trigger coupling" on page 208.
T I P
If the channel is DC coupled, you can quickly measure the DC component of the signal by
simply noting its distance from the ground symbol.
If the channel is AC coupled, the DC component of the signal is removed, allowing you to
use greater sensitivity to display the AC component of the signal.