Stanford Research Systems SR865A, Operation Manual

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196 Performance Tests Appendix G
SR865A DSP Lock-in Amplifier
Input Noise
This test measures the lock-in input noise.
Setup
Connect a 50Ω termination to the A input. This grounds the input so the lock
-in's own noise is measured.
Procedure
1) {PRESET} (press [Save Recall], then touch {Recall default}. Touch {Confirm})
2) Use the front panel to make the following adjustments
Touch {Fint} to display the internal frequency keypad
Enter a frequency of 1.0 kHz.
Press [Input Range Down] multiple times
Set the input range to 10 mV.
Press [Sensitivity Down] multiple times
Set the sensitivity to 100 nV.
Press Filter [Slope/ adv ]
Select 12 dB/oct.
Press [Couple]
Select DC coupling.
Press [Ground]
Select shield Ground .
Press [Config] to display the data configuration screen
Touch {Data1 Display} to highlight the green data source.
Touch {Xnoise} to choose Xnoise for Data1.
Touch {Close}
3) Wait at least 1 minute for the reading of Xnoise (green) to stabilize. Record the value of Xnoise.
4) This completes the noise test. Enter the results of this test in the test record at the end of this
section.