CheapStat
= " a portable, do-it-yourself and easy-to-use potentiostat which can be made for under $80 using open source hardware and software".
URL = http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0023783
Description
Rebecca Schroeder:
"CheapStat is a portable, do-it-yourself and easy-to-use potentiostat which can be made for under $80 using open source hardware and software. While CheapStat does not have many of the features of commercial potentiostats, these features are often unnecessary for application of the instrument to environmental and public health issues. Among other tested applications, its developers have successfully used CheapStat to measure concentrations of arsenic in water - a problem in countries like India and Bangladesh." (http://earthjournalism.net/stories/what2019s-in-the-water-is-it-an-open-source-water-quality-sensor)