Agilent Technologies 54853A, Service Manual, Page: 52 / 194

Chapter 3: Testing Performance
Offset Performance Test
3–8
Offset Gain Test
12
Make the connections to scope channel 1 as shown below.
Connections
13
Set up the DMM to perform DC voltage measurements.
14
Configure the scope to measure V avg on Channel 1 as follows:
a Press Default Setup.
b Pull down the Utilities menu and select Acquisition. When the Acquisition Setup window
is displayed, enable averaging and set the # of averages to 256.
c Change the vertical sensitivity of channel 1 to 10 mV/div.
d Click the V avg measurement icon on the left side of the screen.
e When the Enter Measurement Info window is displayed, ensure that the V avg function
is set up as follows and then click OK:
Source = Channel 1
Measurement area = Entire Display
Notes:
• Where it is used, it is important to connect the BNC Tee adapter directly to the scope channel input to
minimize ground potential differences between the scope and the test instruments and to ensure that
the DMM measures the input voltage to the scope 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 scope and the external test instruments are
connected to the same AC supply circuit.
• A fairly large number of averages are used in the scope measurements of this section to reduce
measurement noise and to reduce the measurement error due to resolution.
5485x Scope Under Test
Au
x
O
u
t
Ch
an 1 I
N
C
h
a
n
2
IN
Ch
an 3 I
N
Ch
an 4 I
N
Digital Multimeter
BNC Tee
connected directly to
scope channel input
Input