Stanford Research Systems SR785, Руководство по эксплуатации и программированию

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Swept Sine Measurement 1-45
SR785 Dynamic Signal Analyzer
If successive points differ by more than the Slower
Threshold (on either input), then the sweep returns
to the earlier point and continues with no skipping.
This ‘fills’ in the region where the response is
rapidly changing. The sweep continues from this
point, speeding up when allowed and slowing down
when required.
Note that the sweep progress marker at the bottom
of the graph changes speed through the notch.
Auto Resolution greatly shortens the measurement
time while preserving the resolution where
required.
11. Press [Source]
Select the Source menu.
Press <Auto Level Ref> Change the Auto Level Reference.
Select (Channel 2) with the knob and press
[Enter]. Choose Channel 2 as the Auto Level Reference.
Press <Ideal Ref> Change the Ideal Reference level.
Press [1] [0], select (mV) with the knob, and
press [Enter]. Enter 10 mV.
Auto Level will try to maintain the Ch2 signal level
at the Ideal Reference level by changing the source
level at each point of the sweep. The Max Source
sets the largest source output allowed.
This is useful whenever the transfer function has
substantial gain as well as attenuation or if a test
requires a constant level within the device under
test (usually input or output). In this case, Auto
Level is not really required but illustrates its use.
Press [Active Display] Change the active display to DisplayB (which is
still measuring the spectrum of Ch2).