Driver disturbs lock-in amplifier?

[fhyzik]

The LabVIEW driver for the Stanford Research Systems SR830 Lock-in Amplifier, downloaded from the NI web site, does not produce accurate readings of the measured voltages(Channel 1 or Channel 2). It appears the phase has been offset, but no offset was programmed into the device, and the values fluctuate. When the device is programmed either from its front panel, Visual Basic, or other languages under the same conditions it produces accurate results. Can you identify and correct the bug in this driver?

[Randy Solomonson]

Hello-

Be sure the display and output and ratio settings for each channel are apropriate. If this doesn't help, would it be possible to list the values are being used for the SR830 Example.VI? It's probably easiest to enclose a screenshot? Also, please state the expected return values from the instrument (possibly a sample from what VB returned).

Randy Solomonson
Application Engineer
National Instruments