Nice project. Even though some items are in a language I do not understand, the sketch provided me with a better understanding of the MySensors work. Thank you for making the connection of what I know and what I was having trouble understanding.
@OldSurferDude I use this. https://www.homedepot.com/p/Orbit-Solenoid-for-Battery-Operated-Timer-57861/203151515
Instead of having to hold the valve open, i can just pulse it. I use a simple motor controller to pulse it and when i need to close it, pulse it in "reverse". That way I could use a battery and if it only opens once or twice a day it's only a half a second or so of draw off the battery.
I think the comments you make are good. I do have a question about the removing the regulator. I assume you mean the 5V to 3.3V regulator.
I connect to the 5V and I see lot of variation in moisture readings due to the variation in the output of the power supply (solar panel/stepdown). I have a calibration routine for that. The voltage can go as high as 4.2V, which I believe may be bad if I connect the power supply to 3.3V.
Of course, this is not a concern if using two 1.5V batteries. With batteries, the moisture reading would be more consistent over a day. Lot of advantages there. I just don't like changing batteries and I really hate it when they leak. I have every reason to believe that my power supply will last 10 years and I am fortunate to live in a place with consistent sunshine . Someone replicating my project will have to take this into consideration. My design easily accommodates a different power supply.
And my power supply could be used in other projects.
Resistive vs Capacitive sensor. I'm glad you report good results. This gives people options.
Water moisture: I've had good experience with "spraying" the Arduino with clear electronic coating and sealing the enclosure with liquid tape.
-OSD
