Table 20: Equipment Settings For Attenuator Balance Adjustments - Tektronix ADA400A Instruction Manual

Adjustment Procedures
LF CMRR Adjustments
46
3. Switch the gain setting between 10 and 100 while adjusting RV33 for
minimum shift in the oscilloscope trace.
a. Make note of trace position at gain setting of 10.
b. Switch gain setting to 100.
c. Adjust trace to where it was at the gain setting of 10.
d. Repeat steps a to c until there is a minimum amount of shift.
4. Adjust RV32 to center trace on screen.
5. Switch the gain setting from 0.1, 1, 10 and 100 and verify that trace does not
shift more than one division from center.
6. Disconnect setup.
Equipment One digitizing oscilloscope (item 1)
Required
One sine wave generator (item 2)
One dual input coupler (item 6)
One 50 Ω terminator (item 7)
Two coaxial cables (item 9)
One adjustment tool (item 10)
1. Connect the ADA400A to Channel 1 and make the equipment settings
according to Table 20.

Table 20: Equipment Settings for Attenuator Balance Adjustments

ADA400A
+ Input
- - Input
Gain
Upper Bandwidth
Oscilloscope
Vertical gain
Time base
Trigger Source
Sine Wave Generator
Output
Setting
DC
Gnd
1
100 Hz
Setting
1 V/div
20 ms/div
Ch4
Setting
10 Hz
ADA400A Differential Preamplifier