[DIYbio] Re: DIY turbidity meters / OD measurements

hello fellow bio-tinkerers, hi sebastian,

the topic of cheap turbidity meters popped up again in another discussion.

https://groups.google.com/forum/#!msg/diybio/ShsFX3OnN8U/ldByXNQ6ffoJ

i have been developing simple laser-cut shields for arduinos. or also stand-alone units to measure light-absorbtion through the standarized cuvettes:

http://www.thingiverse.com/thing:74415

sorry for the lousy docu sofar...

http://hackteria.org/wiki/index.php/DIY_spectrophotometer#BabyTurbiduino_aka_Daphna-2-MIDI_Converter

laser cutting seems to me more useful for this application. good precision and much faster production. the cut sides of the wood is nice black and light absorbin/non-reflecting. and the device can be assembled layer by layer, embedding the LED and sensors into an optical channel.

at the moment we are using something like a digistump clone, we call it babygnusbuino, based on attiny85 and compatible to arduino ide. it can send/receive data as a midi-device and costs less than 5$. but we have been thinking of additionally communicating to the device using an audio-protocol, meaning we could use the line-in of a smart phone to read the data.

more soon,

marc