Keysight U8903B - Crosstalk Verification; Table 2-4 Crosstalk Specification

2 Performance Verification for Analog Generator
30 Keysight U8903B Service Guide
– Waveform: Sine
– Output amplitude: 1 Vrms
– Output state: ON
4 Set both the U8903B output channel 1 and channel 2 to be tested 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 102.
5 Set the frequency counter gate time to the appropriate setting as given in the “Test
record for frequency accuracy verification” on page 102.
6 Enable the U8903B output channel 1 and record the frequency measurement on the
frequency counter, f
FC
channel 1 in the “Test record for frequency accuracy
verification” on page 102.
7 Enable the U8903B output channel 2 and record the frequency measurement on the
frequency counter, f
FC
channel 2 in the “Test record for frequency accuracy
verification” on page 102.
8 Compute the frequency accuracy using the following equation:
Frequency accuracy = (f
FC
– f
DUT
/ f
DUT
) × 1000000
9 Repeat step 4 to step 8 for the rest of the f
DUT
values to complete the verification of the
U8903B output channel to be tested.
10 Compare the recorded frequency accuracy values to the specification. If the test fails,
adjustment will need to be carried out accordingly.
Crosstalk verification
This test measures the leakage caused by stray capacitance and inductance coupling
between the generator output channels of the U8903B using an external loopback
connection.
1 Connect the U8903B Unbalanced output channel 1 and channel 2 to its own
Unbalanced input channel 1 and channel 2 as shown in Figure 2-4. Preset the U8903B
audio analyzer.
Table 2-4 Crosstalk specification
Crosstalk specification Equipment used
≤–130 dB + 0.1 μV (from 20 Hz to 20 kHz) U8903B (external loopback)