Well, the copper weather vane has morphed now into as much of a "steam-punk" weather station as I can muster. As you probably have read elsewhere, I have the weather vane and anemometer built, and the anny actually measuring wind speed. I'm still cogitating on the mechanics of how to read the weather vane position. I've chosen a rather obscure industrial automation controller, because I have lots of parts, it makes me a better programmer for our water company, and because I think it will add to the ultimate steam-punkishness of the final project.
The choice of the controller limits my inputs to discrete switches, and 4-20 ma, and 0-5 volt analog signals. I can also have relay and analog outputs as well as a speech board.
For temperature, I've selected LM34s, which produce a voltage output proportional to the temperature in F. It's actually very easy to read, as the voltage in 10s of mv = the temperature in degrees F. (0.75 volts = 75°).
2 of those, a wick and some distilled water, and a small fan make a psychrometer. I can use those temperature values and the barometric pressure to calculate the relative humidity and dew point.
Now I'm on the track of some analog barometric pressure sensors.
