| Here's one example... we have to measure the current as a function of voltage through some devices that we fabricated at the Birck Nanofabrication Center. It just involves setting the voltage and measuring the current, but doing it manually requires a lot of pushing buttons on the power supply and writing down numbers, entering them into a spread sheet, and graphing them. |
| By using a simple data acquisition system (GPIB over Ethernet) we could use a simple program to set the voltage and read the current, storing the results in a file that could be easily imported and graphed in Excel. |
| This improved several aspects of the measurement. The precision wasn't really improved since one could (in principle) write down all the significant digits by hand, however the systematic uncertainties in the measurements were greatly reduced because the measurements could be made much faster. This meant that the device under test wouldn't heat up with time and possibly change its properties which would happen if the measurements were being made by hand. The data acquisiton system therefore made the measurements much more repeatable. |
| The volume of data would be about the same either way but obviously the data acquisition system would directly record data in a format that could be graphed or analyzed. If it were recorded by hand, it would have to be manually typed into a file with the appropriate format. |