The Mini Pearl Logger is an inexpensive approach to logging environmental data. It is based on an Arduino Pro Mini in combination with a real time clock and a microSD card reader. Those three modules can be purchased (eBay sellers in Asia) for less than US$5.00 (total, including shipping). Adding the microSD card, batteries, wires, etc. can bring the cost of materials close to US$15.00. 

[![MiniPearl_20170606-9521.JPG](https://publiclab.org/system/images/photos/000/021/450/medium/MiniPearl_20170606-9521.JPG)](https://publiclab.org/system/images/photos/000/021/450/original/MiniPearl_20170606-9521.JPG)

Ed Mallon's [Cave Pearl Logger](https://edwardmallon.wordpress.com/2015/10/24/diy-arduino-logger-build-instructions-part-1/) uses a similar combination of components, and Ed has done extensive testing to extend the field longevity to more than a year. We are still trying to replicate Ed's results, and have not yet managed to log data for more than a month on a few AAA batteries.

[![MiniPearl_20170606-9505.JPG](https://publiclab.org/system/images/photos/000/021/451/medium/MiniPearl_20170606-9505.JPG)](https://publiclab.org/system/images/photos/000/021/451/original/MiniPearl_20170606-9505.JPG)

Kits of all the parts needed to solder together a Mini Pearl Logger are [available at the KAPtery](http://kaptery.com/product/mini-pearl-logger-kit).

## Questions

[questions:mini-pearl-logger]


## Activities

[activities:mini-pearl-logger]