Telluric Currents Data CollectionMy DVM (Protek 506) has a serial interface and is supplied with data collection software. I set up the software to collect voltage difference measurements at a rate of one sample per second. This data is saved on disk for later analysis. The data collection software saves the voltage readings in text format in files of 500 samples length. I further process this data with my own software to concatenate individual files into one single file and then convert to binary (4 -byte floating point) values and save to disk. My software can also save the data as a WAV file. My software can display each 500 sample block in the whole record and apply some simple filtering and scaling functions. Below is a screen shot of one of the blocks:- The width of the graph is 500 samples at 1 sample per second - i.e. the above graph is 8.33' minutes wide. The PC I used for these preliminary experiments is a small laptop whose hard drive has gone west and so I can only store about 50 hours of data on the external floppy-drive disk drive. I will have a set up for recording almost unlimited data at 1 sample per second in the future. For analysis of this data see the results page. |