Agilent Technologies NFA Series, Performance Verification And Calibration Manual

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Chapter 2 17
Test Descriptions
10 MHz Out Frequency Reference Accuracy
8. On Channel 1, press Trigger/Sensitivity until Auto Trig is displayed.
9. Use the arrow keys ( —> ) to toggle to Off.
10. Press Freq and Ratio .
Step 5. When the Universal Counter reading has stabilized, record the reading in the
Worksheet as Counter Reading 1 with 0.1 Hz resolution.
This reading is taken as the actual frequency reference of the NFA.
Step 6. Increase the NFA's fine DAC control by 1 step from its initial value.
Press the System key, then the More , More and Service menu keys. Enter the
service password
-2010
, press Enter , then press Service , Time Base , and Fine
menu items. Press the Up Arrow key to increment the Fine control menu item by 1.
The value displayed in the Fine menu item is now 1 more than the initial value.
Step 7. When the frequency counter reading has stabilized, record reading in the Worksheet
as Counter Reading 2 with 0.1 Hz resolution.
Step 8. Decrease the NFA’s fine DAC control by 1 step to return to its initial value detailed
in step 6, then again decrease the NFA’s fine DAC control by 1 step.
Step 9. When the frequency counter reading has stabilized, record the reading in the
Worksheet as Counter Reading 3 with 0.1 Hz resolution.
Step 10. Press Preset on the NFA to return the DAC settings to their initial values.
Step 11. Subtract Counter Reading 1 from Counter Reading 2 and record the difference in the
Worksheet as the Positive Frequency Change.
Positive Frequency Change = Counter Reading 2 - Counter Reading 1
Step 12. Subtract Counter Reading 1 from Counter Reading 3 and record the difference in the
Worksheet as the Negative Frequency Change.
Negative Frequency Change = Counter Reading 1 - Counter Reading 3