Hi Jim,
To change the gain for a channel on your DAQ device, modify the signal input or output range. Either the min/max or high/low properties of the DAQmx Channel specify what gain the DAQ device uses. You do not have to select the physical gain for each channel; the DAQ device automatically chooses the appropriate gain for each channel based on the range that you select. If you do not select a range, the DAQ device uses the default max and min values.
Regards,
Andrew A
Applications Engineer
National Instruments