This is V2 of the wireless temperature and humidity sensor board. The final version is expected to be V3.
Changes from the version to the next (i.e. things wrong with this version):
- Routing fixed (see below).
- Hole locations fixed to fit light switch face plate.
- Board outline narrowed on ends to fit better into electrical box.
- Reset button and ISP header moved to give more clearance to mounting holes.
- Moved battery terminals closer together.
To get the board working you need to cut one trace and rewire it to the correct location. Cutting is easy enough using a hobby knife, magnet wire is good for rewiring.
To strip the ends of the magnet wire for soldering here's a neat trick: turn up the heat on your iron if you have the ability, melt a glob of solder on the end of your iron (as big a glob as you can support) and push the end of the wire in and out of the glob several times. You will see the enamel start to roll up (like a sock) leaving behind a nicely tinned surface.
You will also need an ISP programmer to upload the code. I would highly recommend buying a dedicated programmer(I like this one), but a spare Arduino can be made to work in a pinch.
Bill of materials and firmware will be added to this page soon.