Agilent Technologies 42A, 54621D, 24A, 54621A, 22A, 41A manual To setup the Analog channels

MegaZoom Concepts and Oscilloscope Operation

To setup the Analog channels

Vertical sensitivity Turn the large knob above the channel key to set the sensitivity (volts/division) for the channel. The volts/division knob changes the analog channel sensitivity from 1 mV to 5 V for the 54620-series and from 2 mV to 5 V for the 54640-series in a 1-2-5 step sequence with a 1:1 probe attached. The analog channel Volts/Div value is displayed in the status line.

Vertical expansion The default mode for expanding the signal when you turn the volts/division knob is vertical expansion about the ground level. To set the expansion mode to expand about the center of the screen instead, press Expand in the Utility Options menu and select Center.

Ground level The ground level of the signal for each displayed analog channel is identified by the position of the icon at the far-left side of the display.

Channel position Turn the small channel position knob ( ) to move the channel waveform up or down on the display. The voltage value momentarily displayed in the upper right portion of the display represents the voltage difference between the center graticule and the ground level ( ) icon. It also represents the voltage at the center graticule.

2Press the Coupling softkey to select the input channel coupling.

Coupling changes the channel’s input coupling to either AC (alternating current), DC (direct current), or Ground (hardware ground on 54620-series only). AC coupling places a 3.5 Hz high-pass filter in series with the input waveform that removes any DC offset voltage from the waveform. When AC is selected, “AC” is illuminated on the front panel next to the channel position knob ( ).

•DC coupling is useful for viewing waveforms as low as 0 Hz that do not have large DC offsets.

•AC coupling is useful for viewing waveforms with large DC offsets, or with slowing moving DC offsets.

•Ground coupling (54620-series only) is useful for removing clutter on screen, estimating the baseline noise contribution by the oscilloscope, and measuring the difference between oscilloscope ground and device-under-test ground.

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