Making Instrumentation Accessible: A Homemade Meter-scale Galvanic Resistivity Array

In a field as instrumentally intensive as astronomy, the ability to mitigate equipment costs and develop equipment troubleshooting skills are extremely important yet are often overlooked. Here we describe the construction of a 16-electrode homemade galvanic resistivity array designed that may perform shallow subsurface resistivity surveys. This array is built from commonly available materials and is controlled by an Arduino microcontroller. It may be assembled for approximately $100 using basic tools and readily-available electronic components. The data obtained are comparable to those from commercial models and may be analyzed by standard, freely-available resistivity software. This project shows the educational and monetary potential in teaching students not only how their commercial instruments are made. It also shows how to deal with common problems in electronics and engineering that all researchers face when dealing with complicated electronic instruments, with a particular emphasis on field research.