August 24th, 2011
I’ve sort of wanted a weather station for a long time. Lately, the ham radio hobby has intensified that, and I finally got one. When I finally got the serial link cable yesterday, well I was perhaps irrationally excited. Terah accused me of running all around the house while gathering up stuff for it. That probably wasn’t too inaccurate.
Anyhow, here’s the sensor suite.
The station is a Davis Vantage Vue, and they have pictures of the included receiving console on their site.
On the upper left is the anemometer (wind speed sensor). Next to that is the rain collector for the rain sensor. There is a solar panel on the front for power, and underneath that is the wind direction sensor. The white thing underneath the back is the temperature and humidity sensor, which is inside a radiation shield. There is also a barometer in there someplace.
The indoor console receives the data via a 900MHz wireless link. The console can also be connected via a serial, USB, or Ethernet link to a PC. All sorts of software can then do all sorts of things with it. The console itself, though, keeps a history, has hi/low reports, graphs, and current condition display that is quite useful already. But if course I’d want it hooked up to a computer.
I figured I couldn’t put the console in the basement next to the server due to wireless signal strength issues, but also didn’t want to require my desktop PC to be up for this to work. So I ordered the serial version, and some cheap DB9 to RJ45 adapter jacks. I have CAT6 strung throughout the house, so I simply converted a surplus Ethernet port to a serial port and it worked beautifully.
There are a ton of weather-related programs out there. My requirements said that I wanted something that runs on Linux. Options there include wview, vanprod, RRD Weather Graphs, Weewx, Meteo, and the commercial non-free Weather Display.
That’s quite a few choices. Of those, wview had the best support for various devices from various manufacturers, which I figure might be important down the road.
It can directly generate detailed weather webpages. It can also submit data to Weather Underground. Weather Underground has a feature called “rapid fire” which lets viewers’ screens update with current observations every few seconds. None of the noncommercial programs supported it, so I added it to wview. With my tree, it’s now sending Rapid Fire updates.
It also can submit data to the Citizen Weather Observer Program, which provides a way to both share it with others and provide it to forecasters at the National Weather Service and university researchers. It gets processed by their ingest system and is quality checked against their computerized QC metrics.
Jacob has enjoyed this — he got into assembling it, and often wants to go see if the anemometer is spinning.
And I was surprised to kind of enjoy working with C again. Perhaps that was because I didn’t have to touch malloc() even once?