Naturally, this Lazy Old Geek wanted to add a weather vane (wind direction) to my weather station. Who cares, you may ask? Well, I am a Geek. Actually, wind direction has some importance. Here in the high desert, the winds are usually from the west. But sometimes we get some wrap around and the wind comes from the North or East which usually means it’s coming off the mountains and is probably colder. Also sometimes we actually get smoke blowing in from wildfires in Utah, Nevada and even California.
Example: Outdoor burning by permit is allowed in my county. Just the other day, there was some burning nearby and I could tell by my weather station that it was not going to be blowing in my direction so I could keep my window open.
Step 1: Parts List
Adafruit Data logging shield $19.50
SD Card $ 6
Aluminum NoTrespassing Sign $ 2
Potentiometer 6639S-1-103-ND $12 (Digikey)
2 2”x 1/2” Mending plates $ 1
100ft Ethernet Cat5 cable $ 8 (Amazon)
2 Ethernet Couplers $1.40 (ebay.com)
Prices US dollars March 2011
Any USB Arduino should work but it is easier to wire it up to an Arduino shield so the clone would have to be shield compatible. There are some good deals on ebay for Arduino Duemilanove 2009 for about $18.
So why did I add the Adafruit Data Logging Shield, you may ask? Well, if I want to collect long term weather data say overnight, then I have to leave my computer on. With the data logger, I can record the data to an SD card and don’t have to keep the computer on all night.
The potentiometer is special in that it’s called continuous turn. Most potentiometers rotate about 350 degrees and stop. Those wouldn’t work for a weather vane. This one will keep rotating no matter what direction the wind comes from.