Keysight 8990B Service Manual page 45

13 Calculate the DC gain error using the following equation and record the value
14 Repeat
15 Compare the recorded DC gain error values with the DC gain error limit values
Table 1-5 Test record for DC gain verification
Output
Vertical scale
vol tage
Video input channel 2 (50 Ω)
10 mV/div ±30 mV
20 mV/div ±60 mV
50 mV/div ±150 mV
100 mV/div ±300 mV
200 mV/div ±600 mV
500 mV/div ±1.5 V
1 V/div ±3.0 V
Video input channel 2 (1 MΩ)
10 mV/div ±30 mV
20 mV/div ±60 mV
50 mV/div ±150 mV
100 mV/div ±300 mV
200 mV/div ±600 mV
500 mV/div ±1.5 V
1 V/div ±3.0 V
2 V/div ±6.0 V
5 V/div ±15.0 V
Keysight 8990B Service Guide
in Table 1-5.
D
DC Gain Error = - - - - - - - - - - - -
D
step 3 to step 13
as listed in Table 1-5. If the test fails, refer to
V V
DMM+ DMM–
Performance Verification and Adjustments
V out V scope+ V scope-
–

= - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1

V in V DMM+ V DMM-
–

for video input channel 3.
V
scope+

0.75

–

"Adjustments" on page 51.
V
DC gain error
scope–
1
DC gain error
limit
±2%
±2%
±2%
±2%
±2%
±2%
±2%
±2%
±2%
±2%
±2%
±2%
±2%
±2%
±2%
±2%
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