Agilent Technologies 35670A Service Manual page 256

Adjusting the Analyzer
To adjust the ADC gain, offset and reference
• Set the oscilloscope as follows:
Volts/Div
Channel 1
Offset
Coupling
Channel 2 Volts/Div
Offset
Coupling
Time Base Time/Div
Sweep
Trigger Source
Level
Slope
Mode
Display Mode
Averaging
No. of Avg.
Screen
• Remove the cable from A5 P4. Connect a jumper from A5 TP8 to A5 TP300.
• Press [ ] while setting the power switch to on ( I ).
Preset
• Press the following keys:
[ ]
System Utility
[ ]
MORE
[ ]
SERVICE TESTS
[ ]
ADJUSTMTS
[
ADC ADJUSTMNT
[
SECOND PASS GAIN
Wait for the analyzer to set up the adjustment. The analyzer is ready when the
adjustment message appears on the screen.
• Adjust A5 R407 for a flat trace on the oscilloscope.
• Set the power switch to off (
• Disconnect the capacitive load and connect the 1:1 oscilloscope probe directly
to the oscilloscope input. Attach the probe to A5 TP402 and the probe ground
clip to the instrument chassis.
• Change the set up for the oscilloscope as follows:
Channel 1 Volts/Div
Coupling
Channel 2 Coupling
Time Base Time/Div
Display Averaging
Display time
• Set the power switch to on ( I ).
5-8
20 mV/div
0V
Ω
1 M ac
500 mV/div
0V
Ω
1 M ac
1.0 ms/div
Triggered
Channel 2
500 mV
Positive
Edge
Repetitive
On
8
Single
]
]
).
O
115 mV/div
Ω
1 M dc
Ω
1 M dc
500 ms/div
off
2.00 s
Agilent 35670A