Tektronix TEKFAX ADA400A, Instruction Manual

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Adjustment Procedures
ADA400A Differential Preamplifier
47
2. Connect dual input connector to inputs of ADA400A.
3. Connect 50
Ω
terminator to dual input connector.
4. Connect a coaxial cable from sine wave generator output to 50
Ω
terminator.
5. Connect another coaxial cable from trigger output of sine wave generator to
Ch4 of oscilloscope.
6. Adjust sine wave generator attenuator variable knob for 5 divisions (5 V) on
screen.
7. Set ADA400A ‘--’ input to DC.
8.
Set oscilloscope volts/div to 1 mV.
9. Adjust RV17 for minimum signal amplitude.
10. Disconnect setup.
Equipment
Required One digitizing oscilloscope (item 1)
One sine wave generator (item 2)
One dual input coupler (item 6)
One 50
Ω
terminator (item 7)
Two 10X attenuators (item 8)
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 21.
Table 21: Equipment Settings for CMRR Adjustments
ADA400A Setting
+ Input DC
-- Input Gnd
Gain 100
Upper Bandwidth FULL (1 MHz)
Oscilloscope Setting
Vertical gain, Ch 1 2 mV/div
Time base 5.0 s/div
Acquisition mode Average
CMRR Adjustments