Keysight U8903B, Service Manual

Page: 54 / 165

3 Performance Verification for Analog Analyzer
54 Keysight U8903B Service Guide
6 Enable the U8903B analyzer input channels to be tested.
7 Set the U8903B analyzer measurement function2 to DFD IEC 60268 2nd order and
record the tested channels as DFD
2nd
in “ Test record for DFD verification ” on
page 116 .
8 Set the U8903B analyzer measurement function2 to DFD IEC 60268 3rd order and
record the tested channels as DFD
3rd
in “ Test record for DFD verification ” on page 116 .
9 Repeat step 4 to step 8 for the rest of the input range, Vrms, and f
DUT
values to
complete the verification of the U8903B input channels to be tested.
10 Compare the recorded wideband DFD measurement value to the specification. If the
test fails, adjustment will need to be carried out accordingly.
Residual noise verification
This test verifies if the residual noise of the U8903B is within the published specification by
using shorting connectors to terminate the U8903B input channels and measuring its own
residual noise.
1 Connect the shorting connectors (BNC) to all the U8903B input channels to be tested.
Preset the U8903B DUT.
2 Configure the U8903B analyzer input channels to be tested as follows:
– Connection type: Unbalanced
– Input bandwidth: 90 kHz
– Input coupling: DC
– Voltage detector type: RMS
– Trigger source: Immediate
Table 3-10 Residual noise specification
Residual noise specification Equipment used
≤ 1.3 μ Vrms (for 20 Hz to 20 kHz bandwidth) U8903B
NOTE
Ensure that all the other verification procedures for the U8903B are completed and passed
before performing the residual noise verification.
NOTE
Power on the U8903B audio analyzer for at least 30 minutes before performing the
performance verification.