Stanford Research Systems SR865A, Operation Manual

Page: 202 / 221

184 Performance Tests Appendix G
SR865A DSP Lock-in Amplifier
dc Offset
This test measures the dc offset of the signal input.
Setup
Connect a 50Ω terminator to the A input. This shorts the input so the lock
-in's own dc offset will be
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 1.00 Hz.
Press [Input Range Down] multiple times
Set the input range to 10 mV.
Press [Sensitivity Down] multiple times
Set the sensitivity to 10 mV.
3) Wait at least 10 seconds, then record the reading of R (yellow).
4) Use the front panel to make the following adjustments
Press [Couple]
Select DC coupling.
5) Wait 10 seconds, then record the reading of R (yellow).
6) This completes the dc offset test. Enter the results of this test in the test record at the end of this
section.