Bushnell Backtrack D-Tour

[GPSVisualizer]

Hi all... I'm Adam Schneider, the owner of GPS Visualizer (http://www.gpsvisualizer.com/). I found this forum because someone sent me a .btk track file yesterday... and it was the first I'd heard of the format. For someone who has some experience reverse-engineering GPS data files, it was a pretty easy one: as some of y'all have figured out, the file is full of 24-byte records where the last 16 are the latitude and longitude. The first eight bytes are — I think — the record type (1 byte: "02" for normal points, "04" for end-of-track), temperature (1 byte; divide by 2 and add 20 for the actual temp), point number within the track (2 bytes), and altitude (4 bytes; divide by 10).

Oh, and the 24-byte header line above each track is the record type (1 byte: "03"), then a mystery byte, then the time stamp (7 bytes: 2 for the year, 1 each for m/d/h/m/s), then the rest is blank. The 24-byte header at the very top of the file (which begins with 8 blank bytes) remains a mystery.


GPS Visualizer can already read the basic data from .btk files and convert them to plain text or GPX (http://www.gpsvisualizer.com/convert_input)... but I'd love it if people could send me some additional sample files so that I'm sure I've got it exactly right, and so that I can try to solve the mystery of the time stamps. It'd be really helpful if you could send me a .btk file and a link to a corresponding map page on backtrackdtour.com.

Also, from the discussion above, it looks like this device creates waypoint files too? If so, someone please send me one (or many)!