Calibration Factor; Sensor Calibration Factor Drift - Agilent Technologies E4418B Service Manual

So u(Ms) from the equation above equals:
Mismatch Uncertainty U(Ms) worst case

Calibration factor

The calibration factors supplied with the power sensor take into account the
performance of the sensor with respect to frequency. This value is of secondary
importance when calculating the overall uncertainty of the 1mW reference.
The information that is appropriate is the Uncertainty of the Calibration Factor. The
power sensor must be calibrated such that:
Therefore,

Sensor Calibration Factor Drift

The Agilent Standards Laboratory at South Queensferry has determined the following
average sensor drift value.
Therefore
Note
Agilent E4416A/E4417A Service Guide
Measurement Uncertainty Analysis – Power Reference Level Test
(
0.0244
( ) ±
--------------------------------------------------- -
u Ms =
2P s P d
= =
UM
s
Uncertainty of Calibration Factor < 0.2%
(
U CF
Average Sensor Drift < 0.06% per year
(
U Drift
This value is only valid for 8478B sensors calibrated to 0.2% accuracy.
) × ( )
0.0244
= 0.00042
2
× ( )
2 2 u Ms 0.0012
=
)
= 0.002
)
0.0006
=
Measurement Introduction
B-7