Hi all,
It sounds like for logging ph that standard glass ph sensors drift too fast to be useful. Ion Sensitive Field Effect transistor (ISFET) sensors are now being used on the underwater pH loggers because they hold calibration a lot longer.
I know it's possible to use ISFET sensors for arduino units to hook up to them (example here and library here), but the question is how difficult it would be to actually build something.
I don't have a background in electronics. I can put together arduino stuff, and have become an okay solderer, and follow/adapt instructions well enough to not blow things up (much).
One of the difficult things seems to be actually getting ahold of an ISFET sensor, so actual guides on how to hook up an ISFET sensor to an arduino unit seem to be sparse (I can't find any), so I'm in the dark compared to what I've done so far. Assuming I can get one, how hard would it be to hook it up? For this sensor here they've got a "measurement circuit recommendation". I recognise the pieces in the circuit, but I don't know how an arduino would fit in there (there's 2 Op Amps?).
I'm not asking anyone to give me a step by step, more a vague guess as to how difficult this would be electronically and coding, ranging from "yeah, this would be pretty simple", "wow, I've been doing this for decades and would consider this a challenge!" or "you obviously have no idea, this is completely wrong for this application". If it's doable I'll dig deeper to look at costs and supplies.
Thanks for any guidance.