The reason for my desire to build an accurate weather station is that I need to know the humidity and temperature both inside and outside in order to decide when to have windows open or closed, and when I need to run a dehumidifier as well as the A/C in the summer. My off-the-shelf weather station – which looks beautiful with its full-color LCD, is totally unreliable when it comes to humidity. Probably the temperature is fairly accurate, and relative pressure is fine. Humidity is the most difficult.
So I did a search on the internet to discover (if I could) what was the best and most accurate sensor. The article I found was here:
https://www.kandrsmith.org/RJS/Misc/Hygrometers/calib_many.html
This article convinced me that I wanted to use the Bosh BME280 sensor in my system. Since the sensor is surface-mounted and tiny, I had to find a PCB board with it mounted on (like in the photo). Naturally, I went to the new Radio Shack – Amazon. And sure enough, they had it. Looks just like the one in the photo, but included the connector so it could plug into my prototyping board.
There was already a library for this sensor in GitHub and other places for Arduino. I have not yet received the sensors (they are being shipped from China), but hope to get them soon, and try out the code!