Adjustments

Power Reference Oscillator Level Adjustment

 

Power Reference Oscillator Level Adjustment

 

Description

 

This test adjusts the power level accuracy of the internal 50 MHz

 

oscillator—also called the power reference oscillator.

 

The power reference oscillator output is factory adjusted to 1 mW ±0.4%.

 

This accuracy includes a performance limit of 0.1% and a system

 

measurement uncertainty figure of 0.3% (traceable to the National

 

Physical Laboratory (NPL), UK).

 

 

Note

The setting of the oscillator output accuracy is determined from the

 

system measurement uncertainty plus any chosen test line limit. For

 

example, if a test line limit of 1 mW ±0.2% was chosen while

 

maintaining a system measurement uncertainty of ±0.3%, the overall

 

accuracy of the test setup for the 1 mW power output becomes 0.3% +

 

0.2%, giving a setting accuracy of 0.5%.

 

 

If an equivalent measurement system is employed for post-factory test, the power reference oscillator output can again be set to 1 mW ±0.4%. This setting is sufficient to ensure that the power reference oscillator meets the accuracy specification of ±0.5% after 2 years. This specification includes the ±0.4% setting and also takes into account other factors that will contribute to determining the accuracy after 2 years. The complete breakdown of the ±0.5% specification is as follows:

Test line limit: 0.1%.

System uncertainty: 0.3%.

2 year oscillator drift: 0.04%.

Delta environment: <0.06%.

The following adjustment procedure ensure the power reference oscillator meets the post-factory accuracy setting of ±0.4%.

Note

To ensure maximum accuracy in re-adjusting the power reference

 

oscillator output, this procedure provides step-by-step instructions for

 

using Agilent test instruments of known capability. Signal acquisition

 

criteria may vary if alternative test instruments are used. In such

 

cases refer to the manufacturer’s guidelines for further information.

 

 

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Agilent E4418B/E4419B Service Guide

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Agilent Technologies e4418b, e4419b manual Power Reference Oscillator Level Adjustment