Stanford Research Systems SR780, Operating Manual And Programming Reference

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1-60 Limit Testing
Press <Y0> Select Y0.
Press [-] [1] [0] [Enter]
Enter a value of -10 dBVpk.
Press <X1> Select X1.
Press [1] [2] [0] [0] [0] [Enter]
Enter a value of 12000 Hz.
Press <Y1> Select Y1.
Press [-] [1] [0] [Enter]
Enter a value of -10 dBVpk.
The segment should intersect the signal peak at
10.24 kHz.
Press <Return> Return to the Limit Test menu.
4. Press <Limit Testing>
Select Limit Testing.
Use the knob to select (On) and press [Enter].
Turn Limit Testing on. The limit test result is
displayed to the left of the graph. In this case ‘Fail’
should be shown.
The limit that we drew is an upper limit. Since the
data peak exceed this limit, the test fails.
Press <Edit Limits>
Go back to the Edit Limits menu.
Press <Shift All>
Select Shift All limit segments. This moves all of
the segments together. In this case, there is only one
segment.
Press [7] [Enter]
Enter 7 to move the segment up by 7 dBVpk.
The new segment is above the signal peak and the
limit test passes.
5. Press <New Segment>
Add another segment.
Press <X0> Select X0 first.
Press [2] [0] [0] [0] [0] [Enter]
Enter a value of 20000 Hz.
Press <Y0> Select Y0.
Press [-] [8] [0] [Enter]
Enter a value of -80 dBVpk.
Press <X1> Select X1.