My Home Weather Station

Today I spent about 6 hours on a really cool project.
Last night I bought a home weather station -- something I've wanted for a very, very long time. And no, it's not one of those cheap ones that you stick out the window -- it's a little bit better.
See this one has instruments! No, not musical instruments, but meteorological instruments that measure things like wind speed/direction, temperature, humidity, barometric pressure, rainfall, wind chill, and forecast. All of this is wirelessly transmitted to a receiver that can be kept inside that also gives you indoor temperature readings.

At this very moment 09:53 EST (13:53 UST) (July 24th,2009) my station is reading a 21.1° outdoor temperature, 69% relative humidity, 29.41inch on the barometer, 0.0cm of rainfall, and winds are at a standstill. Earlier this evening we had 3.2km/h winds at 280°
This is a little off from Hamilton's standard weather station at CYHM airport because I am sheltered by trees and houses. However, the idea isn't to have a perfect weather reading, but one centralized to your location. If I needed general city weather I could just look online, or turn on the TV. This one is perfect for planning backyard dining, kite flying, and what to wear in the morning.
By the way, it's a smoldering 26°C inside :|

Thermometer/Hygrometer/Transmitter
This is the most important part of the whole system. The small unit mounts on any flat surface and contains a sensitive thermometer, solid state hygrometer, and a wireless radio transmitter. It has a range of about 100m -- which works great for me. It takes two AA batteries -- lithium is recommended for efficient operation below -10°C. I'll be replacing my alkalines shortly. The unit also covers two RJ 11 cable receptacles for the wind and rain sensors. All of this looks really discrete and clean.

Rain Gauge
The rain gauge is a really simple, yet incredible piece of engineering. On the outside there is an oval structure with a funnel on top. This funnels rain inside the machine towards a see-saw tipping bucket like mechanism. When water hits one side, it sinks and registers a unit of rain. When rain keeps flowing, it makes the mech flop the other way, again, registering rainfall. The more times it flip flops, the more rainfall there is! See! I told you that it was cool! It is imperative that the rain gauge is located on a level surface. To achieve this I mounted it on a piece of a 2x4 and simply placed it on the ground, routing the RJ 11 cable underground and back to the transmitter.

Anemometer/Wind Vane
This was the most difficult, yet fun instrument to install. You see, in my backyard we have a very large tree. I'd say it is the better part of 80 meters and it was one of the only places where I could put the unit without interference from walls or other structures. Ideally, I would have attached it to the chimney on my roof, it is way out in the open -- making it perfect for measurement. It was a combination of both fear and laziness that prevented me from getting up there. So I grabbed the giant 40ft ladder that was laying around and put it halfway on the tree. Believe it or not, it was an incredibly stable platform. Initially, I went up there with a hatchet and hacked away at the bark to expose some hard wood and level out the surface, that was fun, and it weirded out the neighbors. The mounting hardware consisted of a plastic platform that was about 2x2.5 inches. I figured that eventually, attached to a tree, this installation would fail because living wood tends to expand, contract, rot, and grow. So instead I screwed the platform on to a strong 2x4 and drove that whole system into the tree using very large spike nails. Three of them! This, created a very strong, stable, and handsome method of installing the instruments nice and high. Now there is some blockage from the tree, and the wind vane is aligned to the exact north -- but it seems to do its job much better than if I were to put it on a wall (stupid idea) To finish off the installation, I wrapped the main shaft and some of the brackets with camouflage duct tape, making it bird friendly as well!

All together, this system was a great investment! I can't wait for an extreme weather day so that I can really experience all of the instrumentation it its glory!

To conclude I've thrown in a cool set of photos from my flickr account. I'm a pro user now! I love it!