Hi everyone... I've been snooping around for a few weeks and casually reading and building some pretty simple circuits based on an intro book. I've come to the conclusion that it's time to build something for real!
I'm interested in having a weather station, and could use some advice on feasibility and scope.
I saw a youtube video (http://www.youtube.com/watch?v=ATnnMFO60y8) and it made me think that is a good idea. The sun changes position throughout the day, and also throughout the year, so I figured a double axis solar tracker might be cool to try. The guy in the video used 3 photo resistors and calculated difference between the center and each one on the side. Perhaps it would be possible to place the 3 in triangle and calculate a difference not only in the x-axis, but also the y-axis. Two servo motors could be assembled in a similar fashion to what was shown to rotate it literally in any direction. If 3 resistors wouldn't work, maybe 5 assembled in a + sign could be used to calculate differences. Thoughts?
The first issue I run into is how I am going to power it (the tracker and the weather station). Not being familiar with weather station sensors and servo motors, will I need two separate power supply sources (e.g. 2 separate solar panels/batteries)? I don't want to have it plugged in, so that way I can place it wherever I want. I was thinking a solar panel might be good - I live in Houston, TX and it's pretty sunny here. That coupled with a rechargeable LiPo battery might do the trick? I have a nice 9V@1W solar panel from Parallax, and about 5 or 6 of those little garden light solar pannels that, if wired in series, might be able to get me up to 9V in peak day light (maybe 4 or 5V indoors) total.
The second issue is weather I should buy individual sensors and solder them to a breadboard on my own (which has the sense of ownership factor) or should I buy sensors that are already assembled and working with proper circuits? Examples might be the weather station by sparkfun https://www.sparkfun.com/products/8942? and https://www.sparkfun.com/products/10586, or perhaps a complete weather station by Oregon scientific which transmits data via RF 433MHz (http://us.oregonscientific.com/shop/browse.asp?cid=2&scid=48&page=2). I like the idea of purchasing an anemometer because, to be honest, I'm not sure how I would do that myself. But the temperature, humidity, UV, etc. would be easy enough and considerably cheaper to simply buy the sensors and assemble it myself. I also don't necessarily like the idea of all the data transmitting via RF because then I need to have a RF receiver set up somewhere to receive the data, and then send it to the internet. I Think it would be better in the end to invest in a WiFi transmitter and send it directly through my wireless network to the final data repository.
Thanks in advance for reading this long post. Any advice or suggestions on things to consider would be greatly appreciated. I hope to document everything from start to finish so others can easily figure this out. If it's been done before and I missed the post, please point me to the place!