SRS Labs SR850 - Manual (Page 231)

7-13
Performance Tests
5. Amplitude Linearity
This test measures the amplitude linearity. This tests how accurately the lock-in measures a signal smaller
than full scale.
Setup
We will use the frequency synthesizer to provide an accurate frequency and the AC calibrator to provide a
sine wave with an exact amplitude.
Connect the output of the frequency synthesizer to the phase lock input of the calibrator. Connect the output
of the AC calibrator to the A input of the lock-in. Be sure to use the appropriate terminations where required.
Connect the TTL SYNC output of the synthesizer to the Reference Input of the lock-in.
Set the Synthesizer to: Set the AC Calibrator to:
Function Sine Frequency 1 kHz
Frequency 1 kHz Amplitude 1.0000 Vrms
Amplitude 0.5 Vrms Voltage Off
Offset off or 0V Phase Lock On
Sweep off Sense Internal
Modulation none
Procedure
1) {PRESET} (Turn the lock-in off and on with the [
←
] key pressed)
2) Press the keys in the following sequence:
[REF/PHASE]
Use the knob to select External.
Select Rising edge.
[DISPLAY/SCALE]
Highlight the trace number.
Use the knob to select trace 3 (R) for the top display.
[GAIN/TC]
Select 24 dB/oct.
[OUTPUT/OFFSET]
Select R offset and expand.