Tektronix CSA8000 Service Manual page 189

Procedure:
CSA8000 & TDS8000 Instruments and Sampling Modules
Follow this procedure to make the Dark Level and Vertical Equivalent Optical
Noise checks:
1. In the Utilities menu, select System Properties. Check that the Mainframe
Current On-Time is greater than 0.33 hours (20 minutes).
NOTE. The values in System Properties dialog box do not update while the
dialog box is open. Close the dialog box and reopen it to get updated values.
2. Close the System Properties dialog box.
3. In the Utilities menu, select Compensation.
4. Make the following selections in the Compensation dialog box:
a. Under Select Action, select Compensate.
b. Select Module.
c. Select Ch1.
5. Click Execute, and then click OK to the message box that appears.
6. Wait until the compensation is completed (hour glass cursor reverts back to
arrow cursor). It is recommended that you store this compensation result in
the module as the Stored User values. To store the compensation results in
the module, do the following procedure:
a. In the Select Action section of the Compensation dialog box, select
Save.
b. In the Storage section, make sure User is selected.
c. Click the Execute button. This saves the compensation results in the
module.
7. Click Close to close the Compensation dialog box.
8. In the Vert Setup dialog box, click the Optical>> button. This displays fields
for setting up the vertical optical parameters.
9. Select a bandwidth or filter in the Vert Setup dialog box.
10. Press the CLEAR DATA button on the TDS8000 or CSA8000 front panel.
NOTE. If the Vert Setup dialog box covers the Histogram statistics readout at the
right side of the display, click in the Setups title bar and drag the dialog box to
the left until you can see the Histogram statistics.
Optical Sampling Modules
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