The system is designed to collect GPS data along with the resistivity measurement during the survey. It requires a standard NMEA output from the GPS. The software uses the $GGA string. If the OhmMapper G-858 console is used a serial output from the external GPS is required. If it uses a Windows device an external GPS with any interface to the PC is acceptable. If the data logger is an Android device the internal cell phone or tablet GPS can be used.
