Accuracy of hand held GPS

I have a parcel of land that I hunt on.
It is about a 21 acre triangle with the highway being one leg of the triangle.
The other two legs are 1/4 section lines.
The point where those 1/4 section lines meet is in the woods and I don't know within 100 ft where that point is.
How close would a hand held gps unit be for finding that corner?
I'm curious enough to spring for a gps unit but Not curious enough to spring for a survey.
Are they 10 foot accuracy? 30'? 100'?
Are those hand held things hard to learn and use? Anyone know if one brand is better than another?
Thanks for any help.

I run a Garman snowmobiling, and it's fairly accurate. I think it is closer than 100 foot, but I'm not sure how close.

Do you know how many feet down these quarter section line the point is?

Most farm supply stores sell the measuring wheels. Some are set up to measure feet, others are 6.6' in diameter, or 1/10 of a chain. A surveyors chain is 66'. You can wheel a field, that is square, or rectangular, wheel two sides, then multiply wheelsXwheels, count off two decimal points and have acres.

But the point is, a measureing wheel is not all that expensive and would allow you to run down the line and measure the footage each way and find a point in the woods. Provided you know the distance.

Or do you have a lat/longitude description, which a GPS would help you.

Your local Farm Service agency should be able to give you a color, aerial photograph of the place. Helpful to line up reference points and with a little sighting down the line maybe get you to this imaginary point.

The aerial photo usually shows some neighboring land and might show ponds, buildings, other fence rows, etc helpfull in sighting the line.

The FSA black and white photos use to be "to scale", good enough to lay a "Pickett" metal rule on and actually measure off the maps how many "chains", which can be converted to feet easily.

I have one of the little Pickett rules right in front of me, left over from my days working at FSA (ASCS back then)

good luck, Gene

Do you know anybody with a smartphone? They have free apps you can download that do GPS and mapping. The one I used is off by 10-15 feet, I think thats what the handheld GPS units do, but what made it so helpful was, I could walk to known and visable spots and then look at the mapping part to see where the GPS said I was. Example, I walked to several points in my yard that are visable from the satalite maps: mailbox, corner fence post, single tree in the yard, large rock ect. Then I looked at the map and where it said I was. It was always off but it was off consistantly. One day it said I walked a pattern 12 feet due south of my actual route and thats showed up on the aerial map, the red line showed me walking perfectly south of where I knew I walked. A different day, I was 10 feet NNW of my actual route. My point being, GPS may not be perfectly accurate but if you have mapping available, you can look at a known route like I did and make adjustments.

The app I downloaded also has GPS cordinates that can be entered so it will walk you right to your entered point, in your case if you find the missing cordinates on a survey, you can enter that and walk right to it. I havent tested that yet but if on the day I am looking, I can run a known route, look at the map and if the GPS places me 10 feet south of the actual mark, I can input my cordinates, walk to the point and look 10 feet south of there. Just keep in mind that the GPS will show you off a different direction depending on what and how many satalites it syncs up with so do both in the same day as soon as you can.

I mentioned the smart phones because they are pretty common now days, even if you dont have one, you know somebody that does. Using a smart phone with a free app, to me, sure beats buying another gizmo I will only use once or twice. That and it workes way better than I ever thought it would.

My dog tracking collar (Garmin) shows the dogs as "Near" if less than 12-15 feet away. I think they are fairly accurate.

Larry

I do crop adjusting work, and have one of the older, Garmin, Etrex ledgends. It is blue.

It was one of the cheapest ones when I bought it, and it will measure acres. Some of the more expensive ones would not.

Mine is probably 8 years old.

The more satellites you let it "find" the more accurate it is.

When measuring acres, I always tried to wait till it says its accuracy gets below 10'. It may start out saying 25-30 foot accuracy, then gets better the more satellites it picks up.

Gene

You can get a start by looking at http://acme.com/planimeter. You need to see or know the bearings of the 1/4 section line. They are not always a given. Is there a plat filled with the county that shows bearing and distances. Are there any other know lines in the area. I have use many GPS on ground and in the air. Old ones were within 300'. New ones can get down within a few feet.

The gps in my truck claims to be acurate within 3'. I know it will say your out of route if you have to drive on the shoulder for road construction.

I have a Garmin that I use for ice fishing and I can go back to the same hole covered with snow within a foot or less. I have tried using it in the woods but if you have a heavy leaf cover it doesn't work so good. I know where ere is one you can get for free if you can find it under 8 foot of water. Its funny how something can fall out of your pocket and land in a 5 inch hole with solid ice all around it

The satellites drift a bit, so from one month to the next, you can 'move' 20 feet....

If you have a known starting point - one of your corners? And you have a good view of the whole sky to get a lot of satellites then you can work from there with it and get within 10 feet, likely within a foot.

The high tech units that cost a bundle use some point on land (RTK from a tower) and so they always know where that fixed point is, and where the satellites place you, and can get within an inch or less. You sort of emulate this if you are dead certain of one point, and you can work fast enough that the satelte drift doesn't move you too much.

Mine has a feature of adding better sensitivity, uses a bit more battery power, to do the 3 foot accuracy, vs a 10 foot accuracy.

Paul

As others have mentioned it depends a little on how many satellites it can "see" so can be quite a bit off if there is a dense cover, but if you have minimum cover you should be able to get within 3'. I have an old hand-held that would work for this application, but haven't pulled it out of the drawer in years since the cell phones have GPS. I'd pack it and send it for $10 plus shipping. Only reason I'd charge is just to cover the packaging and little bit of time to take it past the PO. It's a "Magellan GPS 315". Really ancient by todays standards, it is basically just a receiver intended to be used as a sophisticated compass or an input to a laptop map program, but you can enter a bearing and distance and follow it. If you have any interest I will have to find some fresh batteries or take it out to a car and make sure it actually works.

Kirk
Magellan 315 Review

I have a garmin Oregon 450 and it works amazing I use it for a variety of things mainly hunting. It costs about 250 on amazon

I have used them for Geo-caching. That is where you find things that others have hidden and you get the cordinents from a web site for your area. I have found accuracy to be at times within 2 feet. Sometimes not that close. I have also taken a long-lat way-point from the gps and put it in Google earth and it puts me at the exact place i was standing.

I had 5 students in the back of my PU on a dirt road when we were done I superimposed the image on a USGS topo map and it was very good. + or - less than a foot. One student moved from one side to the other in the bed. That was shown clearly on the map. The return trip was seen to be clearly down the right side of the road, and the out bound trip on its right side.
Take more than one reading in a 30 minute span using different Satellites, put bright rag markers on each, then average them. Jim

If you know the property #, you can go on the county website here, and get a aerial pic, with the property lines superimposed on the pic. I had my place surveyed a few years ago, and the lines on the pic were right on the money.

>The satellites drift a bit, so from one month to the next, you can 'move' 20 feet.

GPS satellites are not in geostationary orbit, if that's what you're thinking.

The GPS on an iPhone is said to be with in a 5-10' accuracy rating. We used them for a GIS class and they were pretty darn accurate.

I bought a hand held in 97 for marking fishing spots on the lake. That was when they were still scrambling the signals. Some times it was within a few feet but I had it be a quarter mile off at times. It was really frustrating. I don't remember when they quit scrambling, few years after that and then it is pretty good within a few feet. Never use it anymore as it is obsolete and have no need for one. At that time you could subscribe to a signal from towers that corrected the signal somehow. I believe that is what the units on combines etc were using back then. No idea what they are using now. We had a small parcel surveyed a few years ago and he used a gps signal right down to the gnat's hair.

I have a Garmin eTrax 20

It replaced an older GPS that I had for several years.

I use it get get exact locations and measure crop areas. I am
amazed a its speed and accuracy. It is accurate to within an inch or
so of really expensive surveyors equipment. Cost about $300 with
full Australian topographical map loaded. Probably cost half that in
USA

Thanks for the info fellas. Thanks for the offers too.
I do have an android/smart phone and looked at gps apps for it but assumed they wouldn't be very close.
I will look into those more.