With the hackerspace open day coming up in a bit over a month, this is a perfect time to prepare some small projects. Something that can be completed in a few evenings, and is reasonably accessible to curious newcomers. A fellow hacker ordered a few nRF24 wireless transceivers a while ago, and now is as good a time as any to do something with them.
A little about the nRF24
The nRF24 is a 2.4GHz wireless transceiver that is available from a large amount of resellers, from about 2 USD. While they operate in the same ISM band as WiFi, they are not Ethernet devices. There’s at least one well documented library around that provides an interface to them for Arduino, which will provide a starting point for our boondoggle.
The 30 meter range on these I think is pretty reasonable, though it’s nowhere near the 100m that most vendors claim. For those cases where you need the distance coverage, there are models around that will allow for an antenna to be connected. With a simple antenna, distances over 100m in the open field have been reported (see the references article).