Agilent Technologies 85025A, Руководство пользователя и сервисное руководство

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Example A:
The specied return loss for an 85025A detector at 1 GHz is 20 dB . The
measurement uncertainty is 61.4 dB .
If the detector's measured return loss is 20 dB +1.4 dB (21.4 dB or higher), the
detector is denitely within specication.
If the measured return loss is within the specied return loss plus-or-minus the
measurement uncertainty , the detector may or may not be within specication.
One way to reduce the measurement uncertainties is to measure the detector
using a vector network analyzer .
Example B:
If the 85025A in Example A measures 20 dB 61.4 dB (i.e . from 18.6 to 21.4 dB),
it cannot be determined if it is or is not within specication.
If the measured return loss is less than the specied return loss minus the
measurement uncertainty , the detector is denitely out of specication.
Example C:
If the 85025A in Example A and B measured less than 20 dB 01.4 dB (18.6 dB
or less), the detector is denitely out of specication.
The three main sources of error in these measurements come from:
Bridge directivity
Source match of the bridge
Dynamic accuracy of the analyzer
The rst two vary with frequency while dynamic accuracy varies with the
measured return loss amplitude .
T ables 4-2, 4-3, and 4-4 show measurement uncertainty for the 85025A/B ,
85025D , and 85025E detectors , respectively . The tables assume you are using
the corresponding connector-compatible Agilent directional bridges . F or
example , an 85027A bridge with an 85025A detector .
4-4 P erformance T ests Agilent 85025A/B/D/E