Need help reading an Annometer/Wind vane

bomber

A while ago, I bought a toy weather vane at a gift shop. I bought it because I wanted to modify it so one of my BS2s or Propellers could read the sensors (which were designed to be read by a human). I already have 2 out of 4 sensors that are able to be read by a micro. There is temperature (via DS1620), rainfall (conductivity probe) and a light sensor (photocell). All I need to figure out is how to read the Annometer and the wind vane. Pictures will be coming soon.

Mike Green

A lot depends on how the wind vane and anemometer are constructed. Usually an anemometer closes a switch as it rotates or there's a photosensor that detects a reflective spot on the part that rotates or you have a tiny magnet glued to the rotating bit and you have a Hall effect sensor that detects the magnet.

On the wind vane, it depends partly on how accurately you want to read the position. Often there will be some kind of encoder where there's a plastic disc or cylinder glued to the shaft. Have a look at this Wikipedia article for ideas. Shaft encoders can be bought or made.

Iamretired

Take a look at John Owen's article on building a Weather Station and in particular the section on reading the absolute position of a wind vane

http://vwlowen.co.uk/picaxe/weather-station/weather-station.htm

John