Stanford Research Systems SR865A, Operation Manual

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194 Performance Tests Appendix G
SR865A DSP Lock-in Amplifier
dc Outputs and Inputs
This test measures the dc accuracy of the dc outputs and inputs of the lock-in.
Setup
We will use the digital voltmeter (DVM) to measure the dc outputs of the lock-in. Then we will use one
of the outputs to generate a voltage to measure on the dc inputs.
Connect a 50Ω termination to the A input.
Procedure
1) {PRESET} (press [Save Recall], then touch {Recall default}. Touch {Confirm})
Press [Screen Layout] multiple times if needed
Set the screen to show 8 big numerical/bar graphs.
2) For the CH1 and CH2 outputs, repeat steps 2a through 2e.
a) Connect the CH1 (or CH2) output to the DVM. Set the DVM to a 20 V range.
b) Use the front panel to make the following adjustments
Press the CH1 (or CH2) Output <Offset> knob
Turn the offset on. Make sure the OFFSET LED is on.
Press and hold the CH1 (or CH2) Output <Offset> knob
Display the X (or Y) offset keypad.
c) For each of the offsets in the table below, repeat steps 2d and 2e.
Offsets (%)
− 100.00
−
50.00
0.00
50.00
100.00
d) Use the front panel to make the following adjustments
Turn the CH1 (or CH2) Output <Offset> knob to set the offset to the value in the table.
e) Record the DVM reading.
3) For each Aux Output (1, 2, 3 and 4), repeat steps 3a through 3e.
a) Connect the Aux Output (on the rear panel) to the DVM.
b) Use the front panel to make the following adjustments