The Digitraveller was on sale at RS yesterday when I went. It was $70. So, I went ahead and bought one. From reading the info at www.pocketaprs.com
I was able to determine that it did, in fact, output NMEA strings just like other GPS units. The thing I liked about it was that it was small, included a windsheild/dashboard mount, could be powered by batteries or plug, and looked like it would be easy to modify. It also used a standard RJ12 plug, which meant I could make cables VERY easily with common parts.
At $70, it seemed like it was a pretty good deal. Now, if anyone knows the pinout for the RJ12 plug, you'll save me some effort in discovering which is which. I got the PDA version, which comes with connectors for 3 different PDAs. The PC version comes with a DB9 connector, which would make it easy to find out which pins are which.
Modifications I want to make are:
1. adding a 7805 so it can be used with standard 12V power.
2. seeing if I can shoehorn the tinytrakII unit into the case. (I don't think there is room.)
Anyone with more information on these units please post to the group! :^)