GPS software.

“I am looking for software that has the trails on them. That is so silly that these softwared have every point of interest, street,bridge, and railroad, but not the trails. Any suggestions? I have the Sportrak GPS. That is pretty mainstream.”

“Me too!
I've got the Garmin eTrex.

Anybody got the Garmin Geko? That thing is so small and light I'm thinking out getting it to replace the eTrex. Ultralight, ya know!”

“If your talking about software to load into your GPS, I'm afraid your stuck with the stuff offered by the manufacturer, for Magellan that would be MapSend Topo and for Garmin it would be MapSource Topo.

Garmin also has a couple other topo programs available...

National Parks West
National Parks East ...The link does not seem to be working right now.

I cant speak for the Garmin product, but the Magellan Topo program isn't actually that bad. It seems to depend on what you are trying to pull up...some places around here are surprisingly accurate, while others leave a bit to be desired.”

“I have the garmin etrex. (the blue one) Thinking about selling it on ebay. Can't get any satelite reception while hiking. Unless I'm in a treeless area.”

“Bummer. I have read other softwares and they say they are compatable with GPS. I have the Mapsend and it does not show the trails. How stupid it that. I don't know what they are trying to protect. The sales of paper maps.”

“i have the Geko 301...works great as far as i can tell...still playing with it..i'll have it in the sipsey this week so i'll let you know what i learn...The Altimeter is a nice feature.”

“SS...I have a friend that has the same problem with his...there seems to be some debate as to the type of antenna that works best in tree cover. My Magellian works pretty well under tyree cover, I sometimes use it to map x-c routes.

You can find just about anything related to GPS on gpsinformation.net

Bigpoppa...Are you using the Topo program? They use map info from a company called Tiger Maps so they don't have to pay any fees, Garmin uses another map source for the same reason. I gathet both have their good pointa and bad points.

The other programs that say they are compatible with your GPS actually mean you can download tracks, way points and routes to the program installed on your compuiter...you can also upload the same to your GPS, you just can't load the maps themselves.”

“Errr, that was Gemini not SS”

“Ahh. That explains a lot.”

“Thanks OPIE.
Looking forward to your report.”

“My Garmin uses the Mapsource Topo software. It works OK and shows trails. However, there are some inaccuracies from time to time. It doesn't do 3D or profiles like Topo USA does.

I can make a route on the computer and download it to the GPS. I can also upload from the GPS to the computer and play with stuff.

But, like was mentioned, it is for the Garmin products only.”

“mtnsteve- Thanks for the link.

To solve the tree canopy problem, I wonder if a technology can be developed where encoded GPS coordinates can be modulated on or within cellular signals.

At least if there's that mode of operation, you have some signal reinforcement through a different communications methodology.”

“Cellular base stations could be set up as satellite repeaters.”

“Other software is compatible with the Garmins, such as National Geographic TOPO! maps, but only for uploading and downloading waypoints and such. For both the Magellan and the Garmin's, allz you have are the topo programs they offer, which aren't super detailed (Garmin's is at a 1/100,000 scale if I remember correctly), which is not bad and still shows topo lines and creeks and stuff, but not in great detail. Remember, a GPS is not supposed to replace the map and compass, it's just another navigational tool to show where you're goin', where you've been, and how to get back if you lose all visibility. Sorta like flying by instruments if you're a pilot. But always bring along that detailed map and compass and the GPS will help show where you are on your physical topo map.”

“tekdude - It is my understanding that a GPS measures the distance of the wave signal from the satellite in geosynronous orbit and mathematically calculates where you must be on the surface of the earth based on all the 3 or 4 best signals. Anything that delays or deflects the signals reduces accuracy.

Where my son works they sell GPS units...mostly Garmin. They appear to be making them more sensitive all the time.”

“So I did a little reading from some course work years back.

A receiver measures the distance between it and the satellites it reads. In order to get a position, a triangulation (trilateration) process occurs to find a fixed point in space (your location). To get your exact location, a fourth satellite is then read to determine the time it takes for its signal to reach your GPS.

This is done by your receiver generating what's called c/a code (coarse acquisition code).

The time delay between pseudo c/a code transmission and the fourth satellite's normalized transmission time represents a term in the signal's multiplier with light speed.

This is the process that acquires your more precise position. [travel time (c/a delay) x speed of light = distance to your GPS.]

The fact GPS technology is becoming more sensitive is an added benefit. You'd think that increasing the gain of satellite signals would get you some mileage too. Although, there's something about band interference that limits that approach. There are regulatory bodies that specify power transmission levels for this reason.

If terrestrial repeaters were to propagate signals, that is take on the role of downlink repeaters with added gain, well, you'd perhaps have more signal strength to penetrate line-of-sight obstructions.

I wonder what the military does.”

“You'd have to use a different form of modulation and demodulator technologies to collect those signals. FM, PSK, QPSK, PSM, PCM, and PWM, are all forms of modulation that come to mind. AM modulation wouldn't do since that's a form of line-of-sight transmission as well.

So...wireless modems in our GPS receivers. It could happen.”

“BTW- I hear there are wireless satellite transponders nearing commercialization.

Embed one on your kid and know where he/she is at all times (scary, sorta).

Pack one away with you and forget about getting lost. Just subscribe to a specific frequency and you're set. This plus your precision balanced gyroscopic atomic decoder ring and you're easily rescued by SAR in a matter of hours, if not minutes. 8D”

“All you need is an antenna and microprocessor/software to analyze the signals. That could be added to any existing piece of electronics, such as a cellphone. My understanding is that cellphones of the future will have that built in.

Right now airplanes, trucks, trains, and cargo ships are equipped with GPS technology and locations are sent back to a base using satellites. Trucking companies can even tell how fast their trucks are going.

When I fly on airplanes and sit in a window seat I can put my GPS up to the window and see where we are, the airspeed, altitude and ETA. Kinda fun.”

“They sell gps chipsets. Just add your own bells and whistles.

For mapping software there really aren't any decent hiking maps that will load into your GPS. There are several mapping software packages that will exchange information with your gps. I use Maptech Terrain Navigator. It is USGS map format so the trails and new man made features are way outdated, but the topography is very accurate. I can click a route on my computer, print the map, and send the route/track/waypoint to my gps.

When I get back from the trip I can send the any new data back to my Map software.”

“Wow! you ask a simple question and it is amazing what you will recieve. All great information. Thanks. If I can retain 10% of this thread, I will be happy.”

“Are you a Garmin user?”

“I have the Garmin Vista. It has a computer cable attachment, which I haven't used yet. Haven't spent the money on the software yet. the maps in the GPS are sparse and limited in what they show, so I am going to have to break down and experiment with some of this soon...”

“I have an old Garmin 12.

No mapping software at all for my model.”

“I bought a Magellan Gold at Costco. The package included MapSend Topo and MapSend Direct Route (street map). Also came with a vehicle mounting kit, cig lighter adapter/computer cable and 2 32mb SD memory cards. Total cost was $350 + tax but has a $50 mail in rebate. Doing some shopping around showed that the receiver and the topo software alone exceeded (retail) what I paid at Costco.”

“I've been using TOPO! software for a while, and occasionally make it to the National Geographic site (they now own the company that started it) for downloads of updated software. In addition, they also have a library (it grows all the time) of trails already marked, waypoints, etc., that you can download onto your TOPO! program, and save to incorporate into your existing trails database within TOPO!.

I haven't been there for a while, and can't tell you if it has changed much, but it may be worth investigating.

I'm still using my Garmin 12 CX (9 oz.) and it has served me well for the $250 I spent on it. But that was a few years ago, they're lighter now, and have similar if not better features. Am thinking about upgrading mine, but as long as it's functional, I may decide to keep it. Works great.”