Stanford Research Systems SR830, Manual

Page: 128 / 177

6-11
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 [Setup] key pressed)
2) Press the keys in the following sequence:
[Source]
Select External reference mode (INTERNAL led off).
[Trig]
Select POS EDGE.
[Channel 1 Display]
Set the Channel 1 display to R.
[Slope/Oct]
Select 24 dB/oct.
3) For each of the amplitudes listed below, perform steps 3a through 3c.
AC Calibrator Amplitudes
1.0000 Vrms
100.00 mVrms
10.000 mVrms
a) Set the AC calibrator to the amplitude in the table.
b) Wait for the R reading to stabilize. Record the value of R.
4) This completes the amplitude linearity test. Enter the results of this test in the test record at the end of
this section.