npk

Hello everyone, I’m currently working on a project that involves using an NPK sensor that operates at 5V, along with an ESP module. For power, I’m planning to use an 18650 battery rated at 3.7V. I’m wondering about the best way to design the circuit to power for both the NPK sensor and the...

Hi everybody Can anybody advise please, I wish to measure nitrogen,potassium and phostrogen ideally in a leaf sample although soil would suffice. Do the above elements vary conductivity at different frequencies, I have seen a conductivity probe using stainless steel prongs that output npk data...