GPS questions...

[The patriot]

I was looking at two hand held GPS's the other day. One was the Garmin etrex legend, $249. 99, the other was the Lowrance global map 100, $199. 99.

I like the ones with a map built in them, just in case I get lost. I'd use it very seldom out of the truck. Maybe hunting/camping a little. Probibally more as a speedometer checker.

Does anyone own one of these? What's your opinion? Battery life, options, upgradeable, etc. etc. Can I get them cheaper anywhere else?

I really want to use it as a new toy more than anything else.

TIA

Eric

 

[klenger]

I don't have experience with either of those, but I do have a Garmin GPS 12XL. I've had it for about 3 years and has worked very well. No maps but it does show city locations. I mostly use it when I'm hiking and snowshoeing. They all work well and have the same accuracy. Get the one with the functions you like.

 

[Alaskaskiff]

GPS Accuracy

If super accuracy is a key (under 5m) look for the WAAS (wide area augmentation system) feature. This is the system developed for the FAA and uses one of the available channels on the GPS to send corrections. They are starting to be available in all the different models now.

 

[Jacobs]

Lowarance GM 100

I have had a Lowarance GM 100 for over two years. It works very well. I mounted it on the dash just to the left of the cup holder in a '95. It will pick up the satelites it needs to lock on.



The operational time when using dry cell batteries leaves something to be desired. I can get 4-5 hours of operation before I need to change. I always carry 8 extra batteries. It takes 4 at a time.



The operation on 12v when plugged into the truck is good.



I also have the IMS Smartmap CD. This is a really neat tool as it allows you to load detailed maps of a specific area. I use it when hunting. The detail is very good. It shows two track woods roads and more. I am happy with mine.



I found some good info at: http://joe.mehaffey.com/



Enjoy

 

[mvaughn]

GPS

I use a Garmin IIIplus. It is a great unit with lots of features. Only thing is I think it only goes to 999mph.

 

[klenger]

I turned mine on during a flight from Alaska to Salt Lake City for a couple of thousand miles. It's really cool to know where you are at, what altitude, speed, course, etc. I suppose if I tried it now, I either be arrested or beat up by the rest of the passengers.

 

[Scot]

Re: GPS Accuracy

Originally posted by araiha

If super accuracy is a key (under 5m) look for the WAAS (wide area augmentation system) feature. This is the system developed for the FAA and uses one of the available channels on the GPS to send corrections. They are starting to be available in all the different models now.

How much better than 5m? Also are the numbers better with the war on like it was during Desert Storm?



I need to cut a fence line through dense brush and need to basically plot the ends and set a series of way points close enough to be able to sight and saw.

 

[Alaskaskiff]

WAAS GPS accuracy

The standard desired was 5m. In actuality, they have been finding about 2m horizontally and 1m vertically. This isn't a military variant so the disclosure issues are different.

 

[Alaskaskiff]

Accuracy again

The Desert Storm accuracy issue is different from WAAS. That was called Selective Availability, and by Presidential Order (Clinton no less) it was turned off in May of this year, increasing basic GPS accuracy to the levels observed during the Gulf War.

 

[klenger]

I think that selective availability was turned off in 2000, not this year. Clinton wasn't president this year (Thank God). GPS is considerably more accuarte and repeatable with SA off. My position is usually within about 50 feet with standard GPS.

 

[Alaskaskiff]

2000 v 2001

klenger, believe you are right. Lost a year somehow.

 

[Shelby Griggs]

Re: Re: GPS Accuracy

Originally posted by Scot





How much better than 5m? Also are the numbers better with the war on like it was during Desert Storm?



I need to cut a fence line through dense brush and need to basically plot the ends and set a series of way points close enough to be able to sight and saw.

Scot,



I am a surveyor and use $50K worth of GPS to do what you want to do. I don't believe any hand held unit will be the tool for building a straight fence line. If my under $200 hand held unit would work, I don't imagine I would have spent $50K on one good to a few centimeters. Having said that, you should be able to get to around 10 feet accuracy in my experience if you don't have a lot of canopy. The accuracy is only promised to 10 meters 68% of the time, but a few feet seems more normal.



Shelby