Keysight 8990B Service Manual page 39

System specification:
– Offset accuracy: ±(1.25% of channel offset + 1% of full scale + 1 mV)
Test procedure (zero set)
1 Turn on the 8990B and multimeter.
2 Allow the system to warm up for approximately an hour.
3 Press Default Setup on the 8990B to set the 8990B to its default settings, and
4 Enable video averaging and set the video average count to 256 on channel 2.
5 Set the input impedance for the video input channel 2 to 50 Ω.
6 Set the vertical scale for the video input channel 2 to 10 mV/div.
7 Press Clear Display, and wait for the average count to reach 256.
8 Record the mean value of the average reading in V
9 Repeat
10 Repeat
11 Ensure that the V
Keysight 8990B Service Guide
turn on video input channel 2.
The video averaging will be displayed on the Status view.
step 6 to step 8
step 6 to step 9
zero-error
Performance Verification and Adjustments
for the rest of the vertical scale setting in
with the input impedance set to 1 MΩ.
is less than the V
zero-error
in Table 1-4.
zero-error
Table
limit as shown in Table
1
1-4.
1-4.
39