Stanford Research Systems SR844, User Manual

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Performance Tests 5-15
SR844 RF Lock-In Amplifier
6. DC Outputs and Inputs
This test measures the DC accuracy of the DC outputs and inputs of the SR844.
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 50
Ω
termination to the SIGNAL IN.
Procedure
1) Press
Shift
then
Recall
to restore the factory preset instrument settings.
2) For the CH1 and CH2 outputs, repeat steps 2.1 through 2.4:
2.1) Connect the CH1 (or CH2) output to the DVM. Set the DVM to the 20 Vdc range.
2.2) Press CH1 (or CH2) Offset On/Off to turn XYOffs on.
2.3) Press CH1 (or CH2) Offset Modify to see the offset in the Reference display.
2.4) For each of the offsets in the table below, repeat steps 2.4.1 and 2.4.2:
Offset [%]
–100.00
–50.00
0.00
50.00
100.00
2.4.1) Use the knob to set the offset to the value in the table.
2.4.2) Record the DVM reading.
3) For the AUX OUT 1 and AUX OUT 2 outputs, repeat steps 3.1 through 3.3:
3.1) Connect AUX OUT 1 (or AUX OUT 2) to the DVM. Set the DVM to the 20 Vdc range.
3.2) Press AuxOut once or twice until the AxOut1 (or AxOut2 ) setting shows on the
Reference display.
3.3) For each of the output voltages in the table below, repeat steps 3.3.1 and 3.3.2: