I am looking into making a capacitive moisture sensor. This has been discussed many times already, but I am not sure what is the better option, AC or DC.
I want to run this off of a battery, so DC should be easier, but I read the following paper (tried to understand as best I could) and they used AC. From looking at it they did this so they could adjust the frequency and found that they had better readings for lower moisture levels at a specific frequency.
Does this make sense? Can anything like this be done with DC?
Or should I just follow this lead and try something like this myself?
I'm new to electronics so bare with me. Thank you in advance.