[george_tlc]

Just as another option (oziexplorer) - not sure how it compares to ON. Anyhow, I'll give you my take on using a laptop or PDA with a navigation program that allows you to use your own data - versus commercial handheld GPS units that require vendor specific maps.


I've used Oziexplorer for a long time (> 10 years). I've also been running OziexplorerCE (on a PDA) for a good 5 years or so.

Ozi on a laptop works great, in oz it is basically the only way to go (Ozi) because of the lack of decent topo maps on handheld GPS units. With topo maps of the entire Oz on the laptop and Ozi running I had full topo capability with all the tracklogs, routes, waypoints etc etc that one could wish for. The only issue is the large laptop an being offroad with dust & bumps etc etc. The laptops never complained, but they are just large and cumbersome regardless of how they are mounted.

Then I started using OziCE on the PDA, all the same capabilities (in a shrunk down format) and compatible with Ozi on the laptop. So, with the PDA mounted on a nice flexarm in good position for the driver to view I now had it all. Full topo capability (and also in the US with the free topo downloads) and the ability to transfer data easily to/from the laptop version as needed. I run a bluetooth GPS mouse and that means just one small USB cable to 'power' the mouse long term (internal battery runs about 6 - 8 hours) and one small power cable for the PDA. No huge mess of wires, no large lumbering laptop and full navigation capability.

There is also a program on the internet that allow you to 'harvest' google earth satellite/aerial imagery data at whatever resolution you need and then convert that into Ozi friendly files. This allows topo and google earth stuff to be available while navigating - very handy to "see" what the lay of the land is versus a straight topo.

Anyhow, if ON has similar capabilities then the combo of your own topo's, google earth satellite/aerial imagery and a laptop/PDA are hard to beat. I've used the PDA and bluetooth GPS standalone (their own batteries) to go on hikes and bike rides - for longer ones I have made some plug/cable converters to use my 14.4V li-ion bike light battery pack to power the PDA and Bluetooth GPS. This would give me days of continuous runtime.

I also run tomtom on my PDA - so I can use the same setup (BT GPS mouse etc) to have full street level routing - I have US and Oz maps loaded in addition to OziCE and the topo maps and some google earth data. 2 gig SD cards for my PDA are so cheap these days.

cheers,
george.