Agilent Technologies NFA Series, Руководство по проверке работоспособности и калибровке

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20 Chapter 2
Test Descriptions
10 MHz Out Frequency Reference Adjustment
10 MHz Out Frequency Reference Adjustment
Test Description
The adjustment applies to NFAs with both the standard 10 MHz frequency reference
and 10 MHz precision frequency reference (Option 1D5).
The adjustment is performed by calculating the actual frequency error in Hertz from
Counter Reading 1 given in the 10 MHz Reference Accuracy Test (see page 14).
The negative or positive error is used to define what the new DAC setting should be.
After the DAC settings are adjusted and saved, the 10 MHz Reference Accuracy
Test is re-run to verify the unit meets it’s published specification.
Required Test Equipment
The frequency standard provides the reference for the Universal Counter. You can
use a company-specific standard in place of the 5071A, provided it meets the critical
specifications listed in Table 2-3.
Table 2-3 10 MHz Out Frequency Reference Adjustment Test Equipment
Equipment description Critical specification for equipment
substitution Recommended model
Universal Counter Time Interval Range: 25ms to 100ms
Single Operation Range: +2.5 to -2.5Vdc
53132A
Frequency Standard Frequency: 10 MHz Timebase Accuracy
(Aging): < 1 x 10
-10
/day
5071A
BNC Lead (X 2) Length 122cm (48 in.), Frequency
10 MHz 10503A