Another useful thing about GPSBabel is the ability to filter your route or track to make sure that it doesn't have too many points. My Garmin has a 500 point limit for tracks and Bikely often makes tracks with thousands of points.
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The way I do it:
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- Run tweaked .gpx file through GPS Babel to ensure ouptut is readable by GPS Trackmaker.
- Use GPS Trackmaker to download the route onto my GPS.
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If you're using a Garmin GPS with a USB cable then GPSBabel will output the route/track directly to the GPS*. You don't have to go through GPS Trackmaker. You need to use the "garmin" format and output file "usb:" for the command line version. It's simpler in the graphical version
The AUK GPS pages recommended above are very good.
Dave
* Well, almost any. Certainly the Etrex models should work.