I got a pH and EC probes from a friend, from a previous project. I only got the probes, with a wire that ends with a screw-in connector (sma).
I searched (as I am in China, on Taobao), and bought a board that seems to be compatible with this probe and has serial interface:
I was planning to use the onboard UART to read from this board. However, its voltage is 5V, while the UART on Raspberry is 3.3V. No-go.
There is also an analog output on that board, which outputs between 0-3.3V depending on the measured pH. I suppose I should be able to use ads1115 to read the voltage, and calibrate this in Mycodo?
Would you recommend me doing this, or better getting a USB 5V UART adapter and writing a custom input for this sensor (it has AT commands for calibration, read a measurement, etc.)?
Another part of the question is for the EC probe. It has the same connector. If I get another board of same type, and use the analog voltage output, should I be able to calibrate it using my manual EC probe? (measuring the same liquid with both, and entering the manual meter value into calibration process in mycodo)?
Would this kind of setup be reasonably reliable?
Cheers, and thanks for your awesome videos Kyle, kickstarted my interest in hydroponics, I built a compact vertical system in the Xinchejian hackerspace in Shanghai. Can’t wait to have the automation done (now I do everything by hand…).