So, a couple of nights ago, I went ahead and assembled the OpenTracker Plus kit that I had ordered from Argent Data Systems. The kit is dead simple to assemble, taking me only about an hour, and I was going fairly slowly, checking each solder joint fairly thoroughly. The kit only uses through hole components, and is very relaxing, even for a big fingered guy like me.
I have got a couple of issues with it though.
One of the more interesting design 'features' it has is that it only has a single serial port. This means that you can connect it either to the GPS or to a PC for configuration, but not both simultaneously. This made it somewhat less than completely obvious if it was really functional, at least without wiring up all the cabling you need to attach it to a radio.
The second issue is that it really can only be configured by running a Windows program called otwincfg.exe. I tried running it under wine on my Mac OS X, and while it does startup, it doesn't seem to handle the serial port properly enough to configure it. I then hooked it to my Linux box, and while the initial connection seemed kind of squiffy, after a few resets, I could get in and conifgure my callsign and the like.
Maybe by the weekend, I'll get the necessary data cables hooked up for my VX-3R, and it'll see some service on the air.
Addendum: While digging around, I found my Arduino that I had misplaced, as well as an old Olimex controller board. Each of these boards have pretty much the same hardware capabilities as the Open Tracker, and I think that with some software, a transmit only beacon would be really trivial, and a two way beacon, possible. In digging around, I found some articles from the TAPR/ARRL Digital Communications Conference that would seem to be very useful: