The bottom chamber is my open section, it is mostly enclosed, but has about a 6" opening since it gets so hot down thre... the top chamber is where the humidity sensor is, so that always stays 70-80% humidity... I need a cooling system or to keep my compact florescents seperate from the plant chamber...
The system is a La Crosse Wireless Data Logger. it has a base station, and then you can add 3 more (for a total of 4) the model # is the WS-8610U. Basically it has a serial port which it records 3000 data points (goes back like ~2 weeks) and records every 5 minutes the temp and humidity... then i can download the CSV excel spreadsheet, and make graphs. Very useful, and not too expensive for what it does.
WS-8610U by La Crosse Technology - Tomorrow's Weather Today