GPS Locator Recommendations

[carl88]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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.

Foretrex401.jpg

[LDog]

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-...dp/B008VWNBBE/

2300-180x250.png

[iAmKrzys]

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]

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/#....495!-108.2954

[Leo L.]

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]

Holux M-241 $65

https://www.amazon.com/M-241-Bluetoo.../dp/B000FSQOI4

[Tundracamper]

Holux M-241 $65

https://www.amazon.com/M-241-Bluetoo.../dp/B000FSQOI4

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

[carl88]

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.]

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]

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]

Also, I see that Grand Enchantment Trail is partially mapped on OpenStreetMap: https://hiking.waymarkedtrails.org/#....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.