Is there an GPS unit that will get me within 10 feet of a site?

goverton

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Oct 9, 2010
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I have a Garmin GPS40 and it tells me when I get from 175 feet to 1000 feet from my preset waypoint.
I need something alot more accurate.
Any ideas?
 

TerryC

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goverton said:
I have a Garmin GPS40 and it tells me when I get from 175 feet to 1000 feet from my preset waypoint.
I need something alot more accurate.
Any ideas?
Gov, Most GPS's, by design, will get you to within 10 meters (30 ft) of the marked waypoint. Without your unit in front of me, I will say that 175/1000 feet only represents your "ARRIVING AT" function. Keep moving torwards the waypoint and the message should change to "ARRIVED AT" waypoint. You may also have a window on there that tells the accuracy.... and that number will get smaller as more satellites are tracked. The commercial units used for highway construction and such, are MUCH more accurate. You can pay about $20,000 for a unit that will accurately place you to within a fraction of a millimeter of where you want to be. 10 meters is close enough for me! TTC
 

99thpercentile

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Assuming that you live in the USA and specifically the southern portion of the continental USA, any GPS receiver that has Wide Area Augmentation System (WAAS) capability and can see one of the two satellites should get you better than 3m. If you are near an airport you may get 1m accuracy.
 

mts

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I don't know why the Garmin GPS40 doesn't work well for you. It seems to me like it should.

I tried using a car GPS unit for locating waypoints and I found out that the common car GPS chipsets have a mode which is enabled by default to purposely stop sending coordinate updates when the velocity of the unit gets below a certain point. This is to keep from sending tons of data while the car is essentially sitting still. If you hold a car GPS and walk around slowly, you will not get very good results because you are moving at too slow of a speed so it doesn't update your position. If you start jogging or running instead you will often find that the GPS kicks in again and you can get very close to the standard 30 foot resolution claimed by most GPS devices.

The handheld hiking GPS units should have this mode turned off so that you get constant updates to your current coordinates. But perhaps this unit is the exception. If you walk very slowly does the unit still update your position or do you need to travel at a higher rate of speed to see updates occur?
 
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goverton

goverton

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Oct 9, 2010
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mts said:
I don't know why the Garmin GPS40 doesn't work well for you. It seems to me like it should.

I tried using a car GPS unit for locating waypoints and I found out that the common car GPS chipsets have a mode which is enabled by default to purposely stop sending coordinate updates when the velocity of the unit gets below a certain point. This is to keep from sending tons of data while the car is essentially sitting still. If you hold a car GPS and walk around slowly, you will not get very good results because you are moving at too slow of a speed so it doesn't update your position. If you start jogging or running instead you will often find that the GPS kicks in again and you can get very close to the standard 30 foot resolution claimed by most GPS devices.

The handheld hiking GPS units should have this mode turned off so that you get constant updates to your current coordinates. But perhaps this unit is the exception. If you walk very slowly does the unit still update your position or do you need to travel at a higher rate of speed to see updates occur?

I have run test with this GPS device and it warns me of approaching waypoint within a 75 yards and then lets me walk right past waypoint before it says I am there.
What I am doing is pre-programing waypoints I want to "visit" when I go to my TH spots. I need it to get me closer than it seems
to when I am testing it out at home( walking moderate pace, stop, mark Waypoint, save and name it. Continue walking a large 1/2 miles circle and when in sight of known waypoint, ask GPS to take me to that waypoint)
 

Neil in West Jersey

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I have found cellar holes by overlaying old maps onto Google Earth and then entering the coordinates on my GPS. I have done it with two entry level units, a Garmin and a Magellan, and both led me right to the cellar holes in the woods. They should be accurate within 20 ft.
 

faribo

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I have a Garmin Oregon 450 and it is usually accurate to 10 or 11 feet here in MN. One time in MT it took me on top of the pile I was looking for. I mean 0 foot accuracy that time.
 

AUVnav

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I found this website, but dont know anything about it... Expert GPS It states the software will unlock hidden secrets of the gps40.

I had an unit like this one years ago, I built the datalink for the back to hook it up to a computer, and that worked very well in sorting out what the unit could do, setting waypoints, and routes was much easier....I see that the data cable is very cheap now, and is worth it.

I see the unit for sale here at $40... GPS40 but I am more interested in their shipping department!

gar4.jpg
 

homestead-hunter

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I used to do surveying with AutoCAD, I have a sportak pro WAAS <3m accurcay 95% of the time. I have brought my GPS within 1 foot of a given point. What you do:

Obtain coordinates of a horizontal control point (NGS WEBSITE) make sure your Datum matches the one on the datasheet (and WAAS is turned on!). Add the benchmarks coordinates from the datasheet to your GPS, then hit "GO" make your way to the benchmark and let it sit on the benchmark for at least 10 minutes. Your GPS will give you a distance to your benchmark. Mine showed the benchmark 1 foot away and the elevation was dead on. GPS will get more accurate in a year or two with the new blocks of GPS birds they are launching.
 

Bum Luck

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All the above are good posts.
 

paullon

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Sweet blog! Great post, I’ll stop by again.
thanks for sharing your thoughts, I haven’t think of this before, keep posting mate!
 

cyberdan

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I know this isn’t what you are asking but here at work I have an old iPad and asked where am I. I am indoors about 10 feet from any window and it showed me on a map. It put me about five feet from a corner and I am about 4 feet from that corner. So it placed me about 9 feet away. That is pretty good. I wonder if this same iPad can be asked to take me to a certain spot?
 

Got-Good-Tones

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Check out following url: https://usngcenter.org/portfolio-item/apps/

Under tab called "Apps & GPS" then "APPS"...little over halfway down the page should see an app called "Mobile USNG"...almost exactly the same as MGRS (Military Grid Reference System"...USNG just displays the numbers a little bit different. Team that up with "Maprika" & "Google Earth" and you have a pretty decent way to overlay old maps in Google Earth and navigate around as well. You can also plug in the USNG coordinates into search bar of Google Earth...and check out your site of interest...:thumbsup: :thumbsup:

Example: Plug following USNG number into Google Earth search bar...12S VD 9797 7614 Will take you to a USA landmark...:headbang: Give ya a hint...it's in Arizona...:thumbsup:
 
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Kype

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I literally just received my Garmin etrex20 in the mail today. I did a test run in my backyard. I made waypoint 1 my home. And way point 2 the edge of my backyard. The gps signaled I was arriving at my destination at about 10 yards. But once I switched over to the compass. It started bringing me into feet.
 

IDXMonster

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My CTX will get back to a Find Point within 10 feet for Christ sake...other GPS isn’t that accurate??
 

smokeythecat

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I have a Garmin GPS64. What I use it for is to mark an "X" where I have found something good in the ground. When I find something nice, I mark an electronic waypoint. Knowing where I was within a few feet, I can zoom in on it and literally walk to the spot within inches.
 

Sidevalve45

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Correct me if I'm wrong but I believe it makes a difference where the satellites are that your unit is using. If your tracking satellites that are low on the horizon the accuracy will be less than if you have satellite oriented more overhead. Ideally you'd have a nice triangulation of three to get a good location result. Mine has been as accurate as 9' with WAAS.
 

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