Keysight Technologies N8262A, Service Manual

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2 Performance Tests
48 Keysight N8262A Service Guide
Time Base Frequency Accuracy
Description
The accuracy of the 100 MHz sample clock determines the accuracy of all
measurements that are based on samples taken over time. This test measures the
time base by dividing the sample clock by 10 (within the meter) and feeding it out
of the trigger output connector, where it can be directly measured by a frequency
counter.
Equipment
– Required test equipment:
1 unit of 53132A frequency counter
– An alternative frequency counter can be used, as long as it has the appropriate
bandwidth (>10 MHz)
Test method
1 Enable the path that routes the time base signal to the trigger output
connector.
2 Using the 53132A, measure the frequency of the signal at the trigger output
connector.
NOTE
– This test can be configured manually via the command
SERV:BIST:TBAS:STAT ON
, which enables the 10 MHz feed to the trigger
output connector (refer to the Programming Guide for further details on the
use of this command).
– This test can also be configured manually via the front panel; access the
Service menu, select Self Test, and select Time Base to enable the 10 MHz
feed to the Trigger Output connector.
– No adjustment is available for this test if it fails (see Chapter 5,
"Troubleshooting Guide" ).