Keysight 9000 Series Service Manual page 33

Chapter 3: Testing Performance
6 Change the DC Supply voltage to -15 mV.
7 Press [Clear Display] on the scope, wait for the #Avgs value to return to 256 and then record the DMM
voltage reading (Vdmm- column) and the scope V avg reading (Vscope- column) in the DC Gain Test
(50 Ω) section of the Performance Test Record.
8 Repeat step 7 for the remaining vertical sensitivities for channel 1 shown in the DC Gain Test (50 Ω)
section of the Performance Test Record.
9 Press [Default Setup], then turn off channel 1 and turn channel 2 display on.
10 Set the DC Supply voltage (External Supply Setting) to +15 mV.
11 Configure the scope to measure V avg on Channel 2.
a Pull down the Setup menu and select Acquisition. When the Acquisition Setup window appears,
enable averaging and set the # of averages to 256.
b Change the vertical scale of channel 2 to 5 mV/div.
c Click the V avg measurement icon on the left side of the screen.
d When the Enter Measurement Info window appears, ensure that the Vavg function is set up as
follows and then click OK:
Source = Channel 2
Measurement area = Entire Display
12 Press [Clear Display] on the scope, wait for the #Avgs value to return to 256 and then record the DMM
voltage reading (Vdmm+) and the scope V avg reading (Vscope+) in the DC Gain Test (50 Ω) section
of the Performance Test Record.
13 Repeat step 12 for the remaining vertical scale settings for channel 2 in the DC Gain Test (50 Ω) section
of the Performance Test Record.
14 Repeat steps 9 through 13 for channels 3 and 4.
15 Repeat steps 1 through 14 using 1 MΩ for the scope input impedance rather than 50 Ω. The steps should
be followed exactly except in step 4(c), you should select the 1 MΩ button from the Impedance section
of the Channel 1 Setup dialog box rather than 50 Ω and all values should be entered in the DC Gain
Test (1 MΩ) section rather than the DC Gain Test (50 Ω) section.
DC Gain Accuracy Test
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