12. Change the oscilloscope setup using the following table:
Push menu button Select menu option Select setting
Trig menu Slope Falling
13. Push the Trigger Level knob to activate the Set To 50% feature. Rotate the Trigger Level knob to adjust the trigger level
as necessary and then check that triggering is stable.
14. Disconnect the test setup.
Check Vertical Position Accuracy
The results of this test and the DC Gain Accuracy test together define the DC Measurement Accuracy of the oscilloscope. The
DC Measurement Accuracy specification encompasses two different ranges of operation over two different attenuator settings.
■
DC Gain Accuracy: Identifies errors, mostly from the A/D converter, when the vertical position (known as offset in these
oscilloscopes) is set to 0 divisions (or a grounded input will show screen center)
■
Vertical Position Accuracy: Identifies errors, mostly from the position control, made when the vertical position is set to a non-
zero value.
The two attenuator settings operate identically, so verification of the attenuation range from -1.8 V to 1.8 V also verifies the
attenuation range of -45 V to 45 V.
1. Set up the oscilloscope as shown in the following table:
Push menu button Select menu option Select setting
Default Setup - -
Channels 1, 2 Probe 1X
Channels 1, 2 Volts/Div 50 mV/div
Trig Menu Source Aux In
1
Mode Mode
Acquire Sample -
Measure Source Channel under test
Measurements Mean
2. Make a spreadsheet approximately as shown in the example in Appendix A. You only need to enter the values for column A
and the equations. The values in columns B, C, D, E, F, and G are examples of the measured or calculated values.
The PDF version of the technical reference manual (which you can download from www.tektronix.com/manuals), includes
an empty spreadsheet for your convenience. To access and save the test spreadsheet, see the instructions in Appendix. A:
Example of a Vertical Position Accuracy test spreadsheet on page A-1.
1
The test operates without a trigger. To maintain uniformity and to avoid false triggering on noise, the Aux In is the recommended source.
Performance verification
22 TBS1000C Series Specification and Performance Verification
To Next Page
Loading...
Need help?
General
