Keysight U8903B, Руководство по обслуживанию

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3 Performance Verification for Analog Analyzer
44 Keysight U8903B Service Guide
– Function 2: AC Voltage
– Sample size: 262144 for 50 Hz and below, and 131072 for 50 Hz and above
6 Set the function generator to produce a sine wave with amplitude of 1 Vrms and
frequency of f
DUT
as given in the “ Test record for frequency accuracy verification ” on
page 111 .
7 Set the U8903B input channels sample size as given in the “ Test record for frequency
accuracy verification ” on page 111 .
8 Set the frequency counter gate time as given in the “ Test record for frequency
accuracy verification ” on page 111 .
9 Enable the function generator output.
10 Using the
FETC? FUNC1,(@1)
SCPI command for the U8903B, record the frequency
measurement on the frequency counter, f
FC
and the U8903B, f
Meas
in the “ Test record
for frequency accuracy verification ” on page 111 .
11 Compute the frequency accuracy of the U8903B using the following equation:
Frequency accuracy = (f
Meas
– f
FC
/ f
FC
) × 1000000
12 Repeat step 6 to step 11 for the rest of the f
DUT
values to complete the verification of
the U8903B input channel to be tested.
13 Repeat step 1 to step 12 to complete the verification of the other U8903B input
channels.
14 Compare the recorded frequency accuracy values to the specification. If the test fails,
adjustment will need to be carried out accordingly.
Phase accuracy verification
This test verifies the phase accuracy of the U8903B analyzer by measuring the phase
difference of a sine wave generated by a function generator to the input channels of the
U8903B.
Table 3-4 Phase accuracy specification
Phase accuracy specification Equipment used
± 2 ° (for < 20 kHz)
± 4 ° (for > 20 kHz)
Function generator
NOTE
Power on the U8903B audio analyzer for at least 30 minutes before performing the
performance verification.