I’m developing a couple of inexpensive data loggers (open source, of course) and looking for some input on sensors. What types are commonly used, and do they require 3V or 5V?
The low-end board is powered by a single AA and uses local memory for storage, with BLE for control and data transfer. It can provide 3V to external sensors. The mid-range board operates at both 3V and 5V, and includes a LoRa radio for long range, wireless data transfer. Any suggestions from the list are most welcome!
I am relatively new to this but have solved a few problems. I can’t really answer your question because I feel like the science objectives would really need to drive the sensor selection. If you are looking to reach a broad audience, then I guess I would go with some generally applicable environmental sensors such as temp/soil moisture/etc. However, I can tell you that precision will be important. For this I use the ads1115 from adafruit. The second problem you will encounter is battery life. I’m not sure what you mean by BLE, but my first attempt at low-power remote sensing was with the Arduino pro mini 8hz 3.3V.
I echo Jeremy Hise . To play with wireless (BLE & LoRa) that can be close to or embedded in the top 6″ of soil then temperature, humidity and soil moisture. Of course so many “dust” sensors floundered in real world conditions that micros don’t like in the circuitry like humidity, and 2.4GH that is absorbed by real world vegetation.