[Malachai Constant]

The reason the mag units work better is they have a quad antenna which is mor sensative than the patch antennas used in the e-treks. I have a gps76 map (garmin) which has a similar antenna. It works well if you pot it in a pocket on the front pack strap so it is held in a vertical position. it takes a external antenna which REI was selling for $30 a few monts ago now $100. The external does not add much if you have a quad except in a car or boat. The Topo! program does a good job of managing waypoints and comes with the state and trail series. Another good program is oziexplorer. Both of these allow you to add routes from USGS maps. They are great to play with between Oct and Deccc when it is to wet to hike but not cold enough to snow.

[Malachai Constant]

you can put the waypoints in seperate files and only load the ones you want. In Ozi they can each up to 12 can be a different color. I do not know for sure about Topo! but think it could be done by saving each as a different .tpg file.

[Newt]

As far as accuracy goes it may depend on how accurate the maps are that we use. I'm certain they aren't 100%. An idea would be to find some recently established monuments with the known coords, take some GPS readings and compare. NN

[tk-421]

[Dante]

[Tom]

Just to clarify, I'm not comparing my route to the USGS mapped trail. Rather, I'm comparing the route my GPS tracked on the way up to the route it tracked on the way down. When I'm on the trail I know the actual variance is at most a foot or two but the GPS doesn't necessarily show me coming down the same path. Very often the entire path is shifted by, i.e. 10 meters. I've always wondered if the time of the day influences the accuracy of the GPS. I don't think the satellites are actually moving during the day though. My understanding is they're always in the same position in the sky.

[tk-421]

[Dante]

I'm just learning about the technology, so I don't know if this is correct BUT the Joe Mehaffey site says-- "If one GPS performs today and another does not perform tomorrow in "identical" circumstances, it proves nothing without further testing. The GPS sattelites MOVE continuously and today they may be in an excellent position and tomorrow when you test they may be in a quite poor visibility situation." http://www.howstuffworks.com/gps1.htm also confirms the sattelites move, but in in very high and predictable orbits. It also discusses other factors (like the accuracy of the quartz clock in the GPS) that can affect accuracy. Joe Mehaffey draws the same conclusion as you, Tom-- "Except for the eTrex models noted above, there is little difference in "in the woods" performance between the various models recommended." As tk-421 suggests, the number of birds your receiver "sees"--particularly WAAS/EGNOS sattelites--is the most important determinant of accuracy, and for any position, that can change over time.

[Dante]

Do you need anything besides the MapSend Topo Software to use the SporTrak Pro? If all I had to buy was the receiver, I'd be more tempted by the Platinum despite its size and weight. However, I'd need to by the more expensive receiver, more memory and maybe a memory card reader . . . P.S. I found it cheaper and NOT on eBay

[Tom]

No, you really don't need any accessiores. You technically don't need the topo lines either (but it would seem silly not to get them since they are ~$20 after rebate). I'd be surprised if you found the pro cheaper (topo lines and shipping included). All in cost for mine was about $246, but it wouldn't be the first time my bargain sleuth skills were called into question.

[Dante]

Cool! You're right I was looking at the price of the unit bundled with some software at the place you linked to. The unit alone is cheaper there than at the other place I found. Looks like $256.48 for the package at current prices (after the rebate).

[Malachai Constant]

Both Garmin and Mag use the 100K USGS maps for their software. Topo! uses the 24K maps which are much more accurate and newer but cannot be loaded into the GPS except for some very expensive Trimble models. The usgs maps are quite accurate near the schanning resolution. The trails on any can be quite a bit off. There are some web sites that list the usgs benchmarks and their locations. You can usually have reliable GPS readings to within 30' and as low as 3' on mountain tops.

[Dante]

Tom's got me pretty much sold on the SporTrak Pro. Is there anyone out there who thinks the Meridian Platinum's larger screen, compass, barometric altimeter and other features would be worth paying another $100 and carrying the additional weigh and bulk?

[Tom]

[Newt]

Being new to the gps thing I have a couple of questions. I have everthing that I have uploaded and generated on the unit and it's getting to be a mess. I would like to keep some stuff but this is getting insane. How do you manage all the waypoints, tracks and routes? Do you download and delete them from the gps and generate new each time?? I've downloaded the tracks etc to topo and whoa, thats a real mess. How do you get rid of that track you get that goes back to your last point that the unit was on? Right now everywhere I've been is connected. Hundreds of miles. Thanks for any help NN