Keysight Technologies Infiniium MXR Series, User Manual

Page: 77 / 116

Testing Performance
6
Keysight Infiniium MXR-Series Real-Time Oscilloscopes User's Guide 77
Procedure
1
Make the connections to oscilloscope channel 1 as shown below.
2
Click Control > Factory Default , then configure the oscilloscope as follows:
a
Click Setup > Acquisition... .
b
In the Acquisition dialog box, enable averaging and set # of Averages to 256.
3
Set the DC Supply voltage (External Supply Setting) to +15 mV.
4
Use the Channel dialog box to set the channel 1 vertical scale to 5 mV/div, and
make sure the input impedance is set to 50 Ω .
5
Drag and drop the Average voltage measurement icon onto the channel 1
waveform.
6
Press [Clear Display] on the oscilloscope, wait for the number of averages to
return to 256, and then record the DMM voltage reading as VDMM+ and the
scope mean V avg reading as VScope+ in Table 9 of the Performance Test
Record.
7
Change the DC Supply voltage to -15 mV.
8
Press [Clear Display] on the oscilloscope, wait for the number of averages to
return to 256, and then record the DMM voltage reading (VDMM- column) and
Channel Input on MXR-Series Oscilloscope
BNC (f) to dual banana
(1251-2277)
6614C DC Supply
NOTE
•
Where the BNC Tee adapter is used, it is important to connect it directly to the oscilloscope
channel input to minimize ground potential differences and to ensure that the DMM measures the
input voltage to the oscilloscope channel as accurately as possible. Differences in ground
potential can be a significant source of measurement error, particularly at high scope sensitivities.
•
It also helps to reduce ground potential differences if the oscilloscope and DMM are connected to
the same AC supply circuit.
•
256 averages are used in the oscilloscope measurements of this section to reduce measurement
noise and to reduce the measurement error due to resolution.