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The ph sensor will die fast if it the membrane is kept dry.


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.


I think it can cost quite a bit less now, but you’re right — it isn’t cheap.


Hello! I'm the author of this project. The website contains a full step by step tutorial https://awot.net/en/guide/tutorial.html for deploying a standalone react app on ESP32.


Any that implements the Client interface. It is not limited to WiFi modules but for example also works with Teensy and the Ethernet shield. I use it with ESP32 and ESP8266 most of the time.


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.


Oh that sounds reasonable, I'll give it a try on one of the next projects. Thanks for making it!


A few people have now completed the tutorial. One of them without any previous programming experience. Based on the feedback I have added some more instructions to parts that were not completely clear.


Sounds like a really interesting project! Thanks for the feedback.


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


So how do you get into the physics of sound?

I don't think I'll be building speakers anytime soon though, but I'm still very much interested in the details of psychoacoustics and sound reproduction.



I'm very interested in the Arduino based pre amp. Do you have a page with your design that I can study? I was thinking about maybe integrating a Lightspeed Attenuator.

Most of all, I'd like the pre amp to automatically turn on the power amp (currently a Gainclone) when a signal starts coming in from the connected Airport Express.

http://diyaudioprojects.com/Solid/DIY-Lightspeed-Passive-Att...


http://www.amb.org/audio/alpha10/

Here's another arduino-based pre-amp. This one includes relay-based stepped attenuators and input selectors. The pcbs are all available as well as the schematics in case you just want to use it as a base for your own project.


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