I saw the La Crosse weather kit at Costco for $80ish dollars and I had to get it. I have been looking at home weather stations for years. I believe that a Davis system that is wireless and has the interface so you can connect to a computer can be over $400.00. Now went ahead and got it, then looked at the reviews online. I know, sorta impulsive. After finding mixed reviews, I soldiered on.
Here are a couple reasons about why I continued with it. One, It is cheap. You should expect it to be cheap. It's housing, in my opinion, is pretty flimsy and if you drop any of it, it will likely break. I am sure after being in the weather for a year or two, it will be in trouble. However, a good Davis unit is many times more expensive. So I can throw this kit completely away every year for many years before getting to the cost of a Davis system. Another plus is it is completely wireless. That is both a benefit and a technical hurdle.
So, this thing is WIRELESS and is the typical 900MHz auto sync'er upper thingy that is designed to be easy, but can also be frustrating. One thing you have to consider: A LOT OF THINGS ARE IN THIS FREQUENCY SPACE. You and your neighbors have tons of wireless gadgets this thing may have to fight with. It is possible you won't be able to get it to work at your house. This is one reason you should buy this thing from someplace where you can return for refund without a hassle.
The instructions on setting up the unit, although brief, is complete enough to easily set it up. And the part about getting your weather units synced up and working should be followed as they print it. There is a good reason for this. You may assume, like I did, that the wind unit, the rain unit, and the temperature/humidity unit all transmit their readings to the base unit. That is NOT correct. The wind unit and the rain unit transmits its readings to the temperature/humidity unit. The temperature/humidity unit transmits its readings and the readings from the other two units to the base unit. So it is important to follow this order (as indicated in the instructions):
1. no batteries in anything
2. with the wind unit charged up (at least a couple hours in the Sun if 1st time install), press the reset button
3. put the batteries in the rain unit
4. put the batteries in the temperature/humidity unit
5. put the batteries in the base station.
Now you may find this wireless setup a bit odd. But actually, it is VERY NICE. See, there is 200 ft line of sight* range between the base station and the temperature unit. And there is 200 ft line of sight range from the temperature/humidity unit to the rain and wind units. That means your rain and wind units can be 400 ft from the base station. This greatly increases the flexibility of placing the units around your house. Since there is this 'relaying' of information between the units, you can do things like placing them on different sides of the house which would not be possible if they all went back to the base station.
*Remember that the ranges are line of sight. While 900Mhz stuff can penetrate walls and bounce around some, trying to get them to communicate like this greatly reduces the range. When placing the units, try to place them with none or as little obstructions as possible. For example, if you can see the temperature/humidity unit from the Wind unit, that is perfect. Speaking of ranges, there is a 60 ft line of sight limitation from the base station to a computer. It comes with its own transceiver and the communication is the same 900Mhz technology the rest of the kit is using.
Once they are synced up (and as long as you don't have interference issues), they should stay that way until you move the units around or have to change the batteries. Therefore you want to place these units where you can get to them easily. If you move any unit (including your computer), expect to have to repeat the resync process. Fortunately, the sync procedure between the computer and base station is independent of the weather stations so if you need to resync the computer, you won't likely have to resync your outside stations.
Now, these things are outside. The wind unit is powered by an internal battery that is charged by a solar panel. The rain, temperature/humidity, and the base station use batteries. They give you a nice set of alkaline batteries for the units. Keep in mind that alkaline batteries seriously loses power when gets really cold (all batteries do to some extent). I have elected to get some AA Lithium batteries (not rechargeable ion) and use shells to convert them to C batteries for the temperature/humidity unit (no need to worry about the indoor unit). AA Lithium is usually close to the capacity rating as alkaline C batteries at normal temperatures and do a much better job at freezing temperatures. If you are located in a very cold climate, no small battery may work for you. I wouldn't go as far as getting lithium batteries until you have everything working and are comfortable with the setup (no need to spend extra money on something you will throw away :) )
I recommend getting everything working to the base station first. And let it run for like a week or so. Make sure it is functioning and everything. Then move on to getting it working to the computer.
They provide a link to the software La Crosse produced for this unit called Heavy Weather. Make sure you get the right version for the unit you have. They also provided a USB stick that is your transceiver. You basically plug in the USB stick. Install the software. It either comes up trying to sync or you go to a pulldown to tell it to resync. I would go to the base station, hold the RAIN down button til it beeps, then go and tell the software to resync after you have installed the software and started it. If it is in range, it syncs up very quickly. Remember, you only have a 60ft line of site between the base station and the computer, so the computer can't be too far from the base station. That means you may be able to be one 1 room over if going through a wall (and that's a big maybe). This brings up another minus, if you are expecting to use Cumulus or another popular 3rd party weather software, it will likely not work. You should assume to stick with this software and I highly recommend using as computer running the Microsoft Windows Operating System since I have seen some complaints trying to use a Mac. I let this run for a few days to verify it is working correctly and it stays connected. Under Extras->Options, I also changed the update interval to 1 minute and selected to keep the communications to the base station in high speed mode.
I picked a old machine running Windows XP Pro to be my weather relaying PC. I did this because I checked online and I found out there is a product called WUHU which can upload data from various weather stations to Weather Underground, including this unit. You can get WUHU from http://home.comcast.net/~wuhu_software/ . It works well, however, I have read there has been issues with WUHU running with newer versions of Windows (and some issues with Heavy Weather as well). So I picked Windows XP to avoid any issues. The install was easy, I installed with default options and I started it. I told it to run as standalone for now (not uploading to Weather Underground) and went into the config to tell it to look at c:\Document and Settings\All Users\Application Data\currdat.lst by selecting the La Cross option in the pulldown that mentioned that file. After a minute or so, it populated the screen with readings from the base station. For sanity, I compared those readings to what Heavy Weather was saying to make sure there was no mistranslations (I didn't find any). I then logged into Weather Underground and registered the station. It wanted the address, longitude/latitude, elevation of the station. It gave me a 9 character station ID in return. I went into WUHU options, and under heavy weather, gave it that ID and a password (which is the same password as you use to login to your general account on Weather Underground). Went back to Weather Underground and under my stations, it showed it was active almost immediately.
I placed Heavy Weather in the Startup folder of the default user on my Computer so it will start on reboot. WUHU did this for me during it's install. I also configured the registry of the computer to login as the default user automatically. These things aren't running as services so a user needs to be logged in. There are security dangers and you risk making your computer not boot by changing the registry so I'll leave you to search for that if you choose to take those risks. I also changed the BIOS settings of my machine to turn on on power failure.
So far I have found the instruments themselves to be very accurate. I suspect the wind vane is a little hyper sensitive and the temperature sensor may be a little slow to react to temperature changes. But otherwise, I am very impressed for it being a very cheap unit. My readings seem to compare well to close-by units I find on Weather Underground.
That's about it. And here is my station:
Please comment if you have any questions!
UPDATE (10/25/2012): After a week or two I noticed that I had issues with the base station dropping from the Heavy Weather software. Not because it lost sync, the software was saying that the USB adapter wasn't there. I am guessing there is some sort of memory leak or other driver crash. If I reboot the system within a certain time frame of the event, the PC would not lose sync with the base station (not really sure why the base station loses sync if this event happens for too long before correcting). I added a scheduled task to reboot the PC once a day (doing a shutdown -r). It has been stable since.