Keysight U8903B, Service Manual

Page: 57 / 165

Performance Verification for Analog Analyzer 3
Keysight U8903B Service Guide 57
5 Set the function generator to produce a sine wave voltage with amplitude of V
IN
and
frequency of f
IN
as given in the “ Test record for wideband sine wave flatness
verification ” on page 117 .
6 On the digital multimeter, set the range as given in the “ Test record for wideband sine
wave flatness verification ” on page 117 .
7 On the U8903B analyzer, set the input range as given in the “ Test record for wideband
sine wave flatness verification ” on page 117 .
8 Enable the function generator output by setting it to ON.
9 Record the digital multimeter measurement, V
DMM
and the U8903B analyzer channel 1
measurement, V
DUT
in the “ Test record for wideband sine wave flatness verification ”
on page 117 .
10 Compute the wideband sine wave flatness using the following equation:
Wideband sine wave flatness (dB) = 20 × log
10
(V
DUT
/ V
DMM
)
11 Repeat step 4 to step 10 for the rest of the frequency f
IN
and amplitude V
IN.
12 Repeat step 1 to step 11 for the U8903B Unbalanced input channel 2 to complete the
verification of the U8903B input channels to be tested.
13 Compare the recorded wideband sine wave flatness to the specifications. If the test
fails, adjustment will need to be carried out accordingly.
Wideband frequency accuracy verification
This test verifies the wideband frequency accuracy of the U8903B analyzer by using the
function generator as a source and the frequency counter as a reference, to ensure that it is
within the published specification.
1 Use three BNC male-to-female T splitters to create a 4-way connection from the
function generator output to the U8903B and frequency counter inputs.
Table 3-12 Wideband frequency accuracy specifications
Wideband frequency accuracy specification Equipment used
±2 ppm ( > 50 kHz)
– Function generator
– Frequency counter
NOTE
Power on the U8903B audio analyzer for at least 30 minutes before performing the
performance verification.