HN user

ljlukkar

16 karma
Posts4
Comments8
View on HN

You need industrial level sensors and the water needs to be flowing constantly through them. I built something similar about 15 years ago and tested many sensors. In the end I had to pay about 1000 dollars for ph and ec meters that did the job reliably. To be honest there is nothing new here. This is how big greenhouses have been operating for decades.

In small scale there is more work maintaining the automated setup and calibrating the sensors than it would take to do the measurements and dosing manually.

Thanks for reporting the the typo. On Arduino Uno the Hello World example including the SPI ethernet driver consumes around 20kb of ROM and 1kb of RAM. On anything more recent the framework memory overhead will not be a problem. There is no dynamic memory allocations and it does not use the String class.

Homemade Speakers 12 years ago

I have degree in computer science but I owe a large part of what I understand about physics and electronics to my speaker building hobby. I highly recommend getting into the physics of sound. It’s actually pretty simple and will teach you how waves behave in general.

http://www.cs.helsinki.fi/u/ljlukkar/labsub/

I’m currently working on a Arduino based pre amp that hosts a rest api for remote controlling: http://tinypic.com/r/15yvj2g/8 http://tinypic.com/r/11vmhld/8 http://tinypic.com/r/jrzfk5/8