Here is the USB XBee Transceiver board I designed and built recently. Its just a simple FTDI USB to Serial converter chip wired up to a USB-B jack and an XBee-PRO XSC 100mW 900MHz Transceiver.
Here is the board I got from BatchPCB, it came out perfectly, only $15 for this little prototype.
And here is the assembled board.
I'm currently working on assembling the second board, batch PCB always sends 2 even when you only order 1. Soon I should have them happily talking to each other miles apart. I hope to build a set of high-gain antennas and see if I can get the maximum advertised distance of 16 miles.
Now for the technical details. This board is available here at BatchPCB.
I drew up this design it gEDA's PCB software. The best open source PCB and circuit designed I have ever used. Below are Tar files with the Gerber files from batch PCB, also a copy converted by batchup.pl (http://forum.sparkfun.com/viewtopic.php?f=16&t=24988) have to give prop's to the scripter, its very convenient. A gEDA sch of the circuit, a pcb file for gEDA PCB, and postscript files showing the pcb design and the schematic.
All the files are in my SVN. And now that BatchPBC is gone the board is up at OSH park. SVN includes ZIP file with Gerber files for OSH Park.
I haven't finished my software for controlling these over the serial port but I am writing it in C++ for Linux, I may go on to make it compileable on Windows and maybe mac, but I am fairly lazy and love Linux. Also note that right now I am only coding control software for use with the AT commands used with the XBee Pro XSC. The other once use slightly different AT commands, and I may add support for them later.
I designed a nice clear acrylic laser cut case for this from Ponoko. The case is on its way in the mail and I will post pictures when it gets here. But for now I did print a stencil of the case and use it to cut a prototype out of some plastic sheet with an old soldering iron. I wore a gas mask and goggles doing it and i would recommend you do the same if you try this. Here are some pictures, the svg for the case is in the SVN.
The bolts are just locked on to the sides of the PCB since I lacked the foresight to put screw holes on the PCB.
And here it is mounted to one of the sides of the case
And finally assembled
Right now I am using a makeshift antenna made from old Wi-Fi antenna from a broken laptop, cant wait for the nicer antennas to get here. I've tested them with these antennas to a distance of about 100 feet and the work great, I linked one into a virtual terminal on my server and was able to connect from up the street with my laptop using the second transceiver. Once I have these all finished up I'm going to have to think of some fun things to make with these transceivers.
I just got the laser cut case from Ponoko, but unfortunately I didn't leave enough clearance on the connection holes so there was a minor crack, I'm increasing the size of the holes by 0.5 mm for the next one. But besides that this thing is so awesome!
Just a note on future plans for these transceivers. I am in the process of making a pair of 15 dBd 19 Element yagi antennas for the radios. Also, now that I have my HAM license and am a primary user of the 900 MHz band I will be building a beefy amplifier for these, maybe even trying EME.