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carl88
12-03-2017, 16:31
Hello,

I'm looking for a GPS recommendation, and am looking for something to provide a pretty specific function - give me "exact" GPS coordinates of where I am.

The only electronic device I carry on trail is an iPod Touch (no GPS chip, no data) and I navigate with paper map and compass. This has served me well, until I got pretty seriously lost on the Grand Enchantment Trail last year. I'm looking to finish the trail this year, but would be reassured by having the ability to pinpoint exactly where I am if needed. In the simplest form, I'd like to be able to push a button and have GPS coordinates appear on a little screen. Nothing fancy!

I'm aware that devices exist to add GPS functionality to the iPod Touch, though they seem to run in the $150 range. Seems like a bit much for something I won't fully use. Also not really interested in buying a smartphone or full GPS unit.

Any recommendations out there?

Thank you!!

Martzy13
12-03-2017, 16:59
Not sure if the Grand Enchantment Trail is on the Guthooks App, as I don't use it but you might try that. Allows you to use the Location services already present on your phone to pinpoint your specific location. Trails can be bought and preloaded into the app, they are very helpful with other things like water sources, shelters, towns, etc.

nsherry61
12-03-2017, 17:26
I'd think about one of the Garmin GPS watches. Super light, multi-function, fairly affordable, although if $150 is making you squirm, maybe a watch isn't the best option.

The cheapest way to go would be an older model smart phone. You don't need to have the phone set up to work as a phone so there's no subscription cost, just use it like (and maybe instead of) your ipod, except you would also have GPS and GPS mapping functionality.

GPS battery life is better on watches and dedicated GPS devices than a cell phone.

Offshore
12-03-2017, 18:52
You're looking for the specific functions of a GPS unit but don't want to buy a GPS unit. That leaves you with buying device that offers GPS functionality - which will most assuredly come at higher price and perhaps poorer performance than a basic GPS handheld. A GPS watch is pricy, and many have iffy GPS performance). A smartphone is very pricey but generally works well. Your best bet is a simple handheld GPS unit such as the Garmin eTrex 10 which will do what you stated you need it to do as well as give you 25 hour battery life on a set of replaceable batteries - for US$109. You won't find a better solution in terms of cost-efficiency, battery life, and data quality.

DownEaster
12-03-2017, 19:08
I'm looking for a GPS recommendation, and am looking for something to provide a pretty specific function - give me "exact" GPS coordinates of where I am.
Consumer grade GPS devices won't give you exact latitude and longitude, but a figure within about 20 meters of your position. Higher-end GPS units (at least from Trimble Navigation, where I used to work) will let you specify the device isn't moving and then time-average the signals from that fixed position, shrinking the 20 meter error down to under 1 meter. (This capability was first used by the U.S. Forest Service, which needed to be able to reliably locate specific trees.) 20 meters is enough error to misidentify which side of a stream or hilltop you might be on, resulting in some understandable confusion.

(Ignore this if your tolerance for the pedantic is low. "GPS coordinates" isn't really a thing you would see, or want to see. Instead, you see latitude and longitude coordinates just as you would on a survey map, plus altitude if your receiver displays that. These three outputs are the result of filtering GPS time delays through the current satellite ephemerides and a world datum, almost always WGS84. The WGS84 datum differs at Greenwich from the one used on published maps by approximately 112 meters. Geographic coordinate conversion should adjust accordingly and prevent you from seeing that discrepancy in GPS coordinates. Because location is defined based on time delays in signals from satellites which are unlikely to be directly overhead, altitude is less reliable than latitude and longitude. On top of that, in some "bulgy" parts of the world, the datum could be off from the actual surface (height above the Earth's center) by up to 100 meters. Altitude is not corrected in the same way as latitude and longitude. But then, our expectations for altitude accuracy are lower because barometric altitude is a poor measurement without constant adjustment to a nearby reference pressure with changes in the weather. So expect horizontal accuracy of about 20 meters, and altitude accuracy of only about 200 meters, from your GPS device.)

carl88
12-03-2017, 19:12
Thank you all for the suggestions. There is no Guthook App for the GET, though the apps do not work with the iPod Touch as it doesn't have a GPS chip.

It's not that I'm opposed to buying a GPS unit, I just feel like most are overkill for what I want to do (price- and weight-wise). I'm fine with just receiving an output of the GPS coordinates instead of a map. I'm almost wondering if it's something I could build myself...

I have thought about replacing the iPod with an older smartphone, which would have a few other benefits as well. I think I'm hesitating to "upgrade" because I have a solution of sorts in mind.

scrabbler
12-03-2017, 19:26
Go to one of the Chinese gear sites and get a modern cell phone for like $70 and call it a day. It'll do GPS all day long, for days in airplane mode. Bestgear.com comes to mind.

carl88
12-03-2017, 19:28
Consumer grade GPS devices won't give you exact latitude and longitude, but a figure within about 20 meters of your position.

Yes, I'm using the term "exact" very loosely. An accuracy of 20 meters is sufficient for my needs, I don't intent to use the device for navigation, just as a last resort for times of desperation. I am surprised though by the high inaccuracy in measuring altitude. Appreciate the explanation!

KCNC
12-03-2017, 19:44
Consumer grade GPS devices won't give you exact latitude and longitude, but a figure within about 20 meters of your position. Higher-end GPS units (at least from Trimble Navigation, where I used to work) will let you specify the device isn't moving and then time-average the signals from that fixed position, shrinking the 20 meter error down to under 1 meter. (This capability was first used by the U.S. Forest Service, which needed to be able to reliably locate specific trees.) 20 meters is enough error to misidentify which side of a stream or hilltop you might be on, resulting in some understandable confusion.

(Ignore this if your tolerance for the pedantic is low. "GPS coordinates" isn't really a thing you would see, or want to see. Instead, you see latitude and longitude coordinates just as you would on a survey map, plus altitude if your receiver displays that. These three outputs are the result of filtering GPS time delays through the current satellite ephemerides and a world datum, almost always WGS84. The WGS84 datum differs at Greenwich from the one used on published maps by approximately 112 meters. Geographic coordinate conversion should adjust accordingly and prevent you from seeing that discrepancy in GPS coordinates. Because location is defined based on time delays in signals from satellites which are unlikely to be directly overhead, altitude is less reliable than latitude and longitude. On top of that, in some "bulgy" parts of the world, the datum could be off from the actual surface (height above the Earth's center) by up to 100 meters. Altitude is not corrected in the same way as latitude and longitude. But then, our expectations for altitude accuracy are lower because barometric altitude is a poor measurement without constant adjustment to a nearby reference pressure with changes in the weather. So expect horizontal accuracy of about 20 meters, and altitude accuracy of only about 200 meters, from your GPS device.)

I rather enjoy the pedantic, especially when it's educational and helpful.

Thanks for providing a level of detail that I haven't been exposed to before. Now I don't have to hunt for something to learn today. :)

LDog
12-04-2017, 00:04
I'm looking to finish the trail this year, but would be reassured by having the ability to pinpoint exactly where I am if needed. In the simplest form, I'd like to be able to push a button and have GPS coordinates appear on a little screen. Nothing fancy!
The Garmin Foretrex line is pretty basic! I have one I used to create tracks of local trails. I don't have the dory wrist strap tho. Tiny thing resides nicely in a hip belt pocket. IPX7 water resistant rating. Weighs 3.1 oz with batteries.

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LDog
12-04-2017, 00:36
You might look at GPS "Loggers" Primarily meant to log track data, but some display current location.

Bad Elph makes a device similar to the foretrex. 3.2 ozs the Pro is available on Amazon for $149. The Pro+ pictured is $236!

https://www.amazon.com/Bad-Elf-2200-Black-silver/dp/B008VWNBBE/

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iAmKrzys
12-04-2017, 00:49
While I primarily use Garmin eTrex 30 when hiking, my cheapest setup that I have come up with till this day, was a cheap pre-paid Android phone (I paid $30 at Walmart) coupled with OSMAnd+ (around $10) and GPS Status app that I think was free. Even when the plan on pre-paid phone expired I am still able to use it over Wi-Fi and OSMAnd+ allows you to download maps based on OpenStreetMap.org before you leave the house.

iAmKrzys
12-04-2017, 00:53
While I primarily use Garmin eTrex 30 when hiking, my cheapest setup that I have come up with till this day, was a cheap pre-paid Android phone (I paid $30 at Walmart) coupled with OSMAnd+ (around $10) and GPS Status app that I think was free. Even when the plan on pre-paid phone expired I am still able to use it over Wi-Fi and OSMAnd+ allows you to download maps based on OpenStreetMap.org before you leave the house.
Also, I see that Grand Enchantment Trail is partially mapped on OpenStreetMap: https://hiking.waymarkedtrails.org/#route?id=3717501&map=10!33.495!-108.2954

Leo L.
12-04-2017, 03:30
Consumer grade GPS devices won't give you exact latitude and longitude, but a figure within about 20 meters of your position...
I disagree here.
Using a Sony Z3 compact smartphone, we had a case last spring during a desert hike when my friend lost an important piece of equipment (one of his three GPS devices, the one which he used to log the hike).
As the piece of desert we were in was in true solitude, we just headed on to come back a few days later to pick up the stuff.
Luckily I had been tracking our hike with my Sony, using Backcounttry Navigator. It was all open desert, gravel and stones with a few tiny sandy spots strewn in, none of our old footsteps we found so far at the start of our search.

So when doing our search, I had the Sony on, BN running and the blue dot following the blue line. I had the impression the blue dot was a tiny bit off to the side of the line - so I took a few steps in the other direction to get better aligned - then looking down to the ground I saw my own footprint from the other day.
So the GPS on my sony was exactly down to the point, accuracy down to a single meter.

I would highly suggest to the OP to get a smartphone and just use it as a GPS device.

Tundracamper
12-04-2017, 07:24
Holux M-241 $65

https://www.amazon.com/M-241-Bluetooth-Battery-Chipset-Waypoints/dp/B000FSQOI4

Tundracamper
12-04-2017, 07:26
Holux M-241 $65

https://www.amazon.com/M-241-Bluetooth-Battery-Chipset-Waypoints/dp/B000FSQOI4

Although it doesn't show it, GPS coordinates display on the tiny LCD display.

carl88
12-04-2017, 08:12
Thank you all for the great recommendations and information, very much appreciated! I will do more research tonight, but looking just at the pictures, it would seem that the Holux device is essentially what I am looking for.

Leo L.
12-04-2017, 08:33
You may try before you buy, how it would work to actually get the GPS coordinates translated into paper map location.
Have to admit that the first time I had a dediacted GPS at hand I failed miserabely at this task.

Uncle Joe
12-04-2017, 09:21
A used iPhone would be about perfect for this. You wouldn't have to activate it to use it like an iTouch and you'd get GPS capability.

handlebar
12-04-2017, 10:10
Also, I see that Grand Enchantment Trail is partially mapped on OpenStreetMap: https://hiking.waymarkedtrails.org/#route?id=3717501&map=10!33.495!-108.2954 As I'm sure you know Blisiterfree (Brett Tucker,) the "father" of the GET posts GPX files with tracks and waypoints that you bought with your purchase of the maps (I assume you did purchase the maps). The recommendation to find a used iPhone (or other smart phone) assuming the battery isn't shot is probably the cheapest option. You might just want to ask around of your friends to see whether they have one. Unfortunately, using an old smart phone might also lead to needing to carry a supplemental battery for recharging since some of the older models don't have good battery life. So you're adding some weight, but eliminating the iPod Touch. I found that Wifi in some of the towns enabled me to contact my wife using Facetime where there was no AT&T signal. If the iPod Touch has a Facetime app, you could leave it behind with someone to allow similar contact.

I made the mistake of not double checking the track on my GPS (Delorme PN-60) and found to my chagrin that the track simply ended. I was hiking the GET westbound this past fall and decided to bail at the CDT paved road crossing west (sourth?) of Winston NM as I'd come to rely on the GPS track. The PN-60 had a limit to the number of track points it could store and only stored the easternmost points. I have since edited the .GPX file from Blisterfree to break it into several separate .GPX files that don't exceed the max and plan to resume my hike this coming spring---this time eastbound from Phoenix.

Greenlight
12-04-2017, 12:02
Post recinded...the particular unit was a dud. Too bad, Magellan makes some nice ones.

Hello,

I'm looking for a GPS recommendation, and am looking for something to provide a pretty specific function - give me "exact" GPS coordinates of where I am.

The only electronic device I carry on trail is an iPod Touch (no GPS chip, no data) and I navigate with paper map and compass. This has served me well, until I got pretty seriously lost on the Grand Enchantment Trail last year. I'm looking to finish the trail this year, but would be reassured by having the ability to pinpoint exactly where I am if needed. In the simplest form, I'd like to be able to push a button and have GPS coordinates appear on a little screen. Nothing fancy!

I'm aware that devices exist to add GPS functionality to the iPod Touch, though they seem to run in the $150 range. Seems like a bit much for something I won't fully use. Also not really interested in buying a smartphone or full GPS unit.

Any recommendations out there?

Thank you!!

colorado_rob
12-04-2017, 12:43
You may try before you buy, how it would work to actually get the GPS coordinates translated into paper map location.
Have to admit that the first time I had a dediacted GPS at hand I failed miserabely at this task.

The maps i print from caltopo and trails illustrated maps both now have a handy grid with coordinates on the margins, both in lat/long and UTM. Speaking of which, the holux i just looked at does not display UTM coords, which is bad. UTM is sooooooo useful out in the field. If you're 300 meters from your desired location per your UTM position, well that makes sense. But if you're .05 degrees, or worse yet, 57 arc seconds, well, tell me how far that is again?

And i know you said not interested in smart phone, but give it another thought. Dirt cheap used ones with outstanding gps receivers, and like said, no need to activate any service plan. Just load any number of outstanding apps sometime when in wifi coverage, and you're good to go. And now you also have a decent camera, music or audio book player and kindle app reader all in one.

nsherry61
12-04-2017, 13:02
. . . But if you're .05 degrees, or worse yet, 57 arc seconds, well, tell me how far that is again? . . .
Is that 0.05 degrees N or 0.05 degrees E?
It's about 3.5 mile N and at the arctic circle it should be about 1/2 that distance E, and what, maybe 2.2 mile E at 45 N? :-? :rolleyes:

colorado_rob
12-04-2017, 13:38
Is that 0.05 degrees N or 0.05 degrees E?
It's about 3.5 mile N and at the arctic circle it should be about 1/2 that distance E, and what, maybe 2.2 mile E at 45 N? :-? :rolleyes:exactly! Still, lots of folks refuse to use UTM, saying they are "used to lat/long". After all, at our moderate latitudes one does get a feel for distances from degrees, minutes and seconds. But once you use UTM, I doubt you would go back.

DownEaster
12-04-2017, 13:59
I disagree here.
...
So the GPS on my sony was exactly down to the point, accuracy down to a single meter.
You disagree?

If you're disagreeing, then you weren't within the 20 meter maximum error. Last I checked, 1 meter is within 20 meters. :D

As I stated, the maximum 20 meter error is relative to surveyed latitude and longitude. You were comparing GPS readings directly, eliminating the coordinate conversion portion of the possible error.

Leo L.
12-04-2017, 14:20
I'm no survey person, but roughly know how GPS (and other satellite) navigation works.
In the above given example, we came back to the place after 3 days, enough time that all satellites had moved around several times and weather had changed and several other details that might influence the accuracy of the GPS.
Still the smartphone could return me to the old location within a single meter or so.
I'm using my Sony for every hike since a few years and most often find its accuracy in the single meter range, correctly indicating wether I'm on the path or not, or on which side of a road I am.
Several apps indicate the given accuracy by a light-blue corona around the blue dot - and this is a tight circle, mostly.

I belive that way, way more money is going from the smartphone industry into developement of utmost sophisticated GPS hard- and software than any of the traditional GPS device manufacturers ever could spend - so I belive that the GPS function in newer smartphones may be at least equal, if not (much) better than in the dedicated handheld GPS.
One shortcoming phones might still have is the lack of a perfect GPS antenna, due to design constraints.
Another issue is the missing acuracy in gorges and at the base of of sheer rock faces. So far I've never had an opportunity to cross-check how a handheld would perform in such cases. Both might be non-issues when hiking.

Hike your own hike, as is stated here many times - I prefer my smartphone.

nsherry61
12-04-2017, 15:15
1st: GPS technology absolutely does NOT provide reliable 1 m accuracy (standard with good signal is 3 m) without a ground based station to augment the satellite data. With a ground based differential system you can get cm accuracy.

2nd: The latest in dedicated GPS technology is absolutely better than cell phone technology, mostly because of the antennas and software processing for less than perfect signals. That is also why one GPS App or your phone will work significantly better than the next . . . a lot of it is software. Of course, the latest in GPS technology is not found in a $200 GPS unit.

3rd: Cell phones rock as highly functional, super user friendly GPS's!!

Leo L.
12-04-2017, 16:02
In lack of better English words, I've used "accuracy".
The position provided will not be accurate in absolute terms, in the above described story. But obviousely it was accurate enough to find the same point than it had found a few days earlier within an "accuracy" (can you call it "repeatability"?) of (a) single meter(s). It could repeat the process and the result, even while the satellites, daytime, weather and some other influences had changed.

Honestly, this was one of the most impressive demonstration of what a smartphone can do, since long.
There was a bit more to the story:
My friend is doing professional exploration of the desert, in terms that he's exploring tracks and paths, to later describe these in books.
He was carrying and running three GPS devices simultaneousely, for redundancy. A lot of weight and money.
Now that he had lost the one GPS that he used for tracking, he had to resort to my tiny Sony for the remaining days. At the end of our journey he loved my Sony so much, that I almost had to fight to get it back.

Leo L.
12-04-2017, 16:22
To add to the above:
During the same journey last spring, for two weeks I was hiking with some other friends in another part of the desert. One had a GPS watch, the other a handheld GPS.
The watch was pretty perfect in getting the vertical height, most often down to about 10 meters or less, compared with the data shown in the maps.
The handheld was less accurate in getting the height, and the Sony was worst in this trade. Usually the height was off by some 50 meters.
But I had the satellite images and the maps from Backcountry Navigator on my Sony, and had so much more information (like the contour lines) than the other two guys.

This is all based on causal observation, no scientific survey.

Alligator
12-04-2017, 16:38
The government has an average user range error of 25.6 ft 95% of the time but actually does better than that. See www.gps.gov/systems/gps/performance/accuracy.

You could test your device over the course of multiple days and times then get an average (with a confidence interval). A USGS survey marker is one place to do that with a known position.

Alligator
12-04-2017, 16:56
The maps i print from caltopo and trails illustrated maps both now have a handy grid with coordinates on the margins, both in lat/long and UTM. Speaking of which, the holux i just looked at does not display UTM coords, which is bad. UTM is sooooooo useful out in the field. If you're 300 meters from your desired location per your UTM position, well that makes sense. But if you're .05 degrees, or worse yet, 57 arc seconds, well, tell me how far that is again?

And i know you said not interested in smart phone, but give it another thought. Dirt cheap used ones with outstanding gps receivers, and like said, no need to activate any service plan. Just load any number of outstanding apps sometime when in wifi coverage, and you're good to go. And now you also have a decent camera, music or audio book player and kindle app reader all in one.You want to make sure the map and the device are using the same datum and projection, just to add further information. UTM projections are regional, for instance, the AT looks to be in at least 3 zones (17-19).
Probably not much of a hiking issue for close zones but perhaps the distortion would be large if you had a far away zone set on the gps device.

Linesman
12-05-2017, 08:32
https://jet.com/product/detail/183c79bb0b2e4e8dabbc4fcbe75b4cbb?jcmp=pla:ggl:nj_d ur_gen_electronics_a1:electronics_gps_navigation_g ps_system_accessories_a1:na:PLA_785706707_43734973 369_aud-320230129885:pla-346594535927_c:na:na:na:2PLA15&code=PLA15&pid=kenshoo_int&c=785706707&is_retargeting=true&clickid=dd8b1541-513e-4767-aaf8-18f925ad6b07&gclid=CjwKCAiApJnRBRBlEiwAPTgmxIaEL7Bf64bcuFSwGO2W dIKflFIZruz_tERqMjFgp7xDuUJVnWn_8BoCcGEQAvD_BwE

cmoulder
12-05-2017, 11:06
I usually get excellent GPS location with my phone, LG V20, using Maprika.

A couple of days ago I initiated Maprika tracking in the parking lot at Woodland Valley in the Catskills, the thinner red line in the screen shot with the yellow circle around the starting point. It was literally within inches of where I started the track... my exact parking spot, at the back of the vehicle.

I've used GPS units since the availability of the Garmin 12XL and the accuracy as just gotten better and better. I have an Etrex 30 but the smartphone GPS is just as accurate and much more user-friendly for uploading maps.

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