Most simple, cheapest GPS receiver recommendation pls

[Bob Gross]

"Btw the US GPS Constellation is in the process of failing due to a lack of funding and a delay in technology. In 5 to 8 years we will be dependent on Glosnass, Galileo and Compass."

Bill, give us your reference for this. Or, is it just an opinion?

Personally, I don't believe that for a microsecond.

For one thing, Compass tends to be China-only. Galileo still has tremendous problems getting off the ground, physically and financially.

Russian GLONASS has been good, then bad, then good again, and I call that unpredictable. Plus, we don't really understand the Russian government/military/management structure for it.

–B.G.–

[Mike W]

>> If the GPS has no digital compass, you have to be moving ~ 1mph? to get a heading. With a digital compass you can stand still and get the heading. <<

I hear this alot and it's not entirely true. When you are standing still your GPS knows exactly where you are and all of the major brands will have a screen that will tell you where North is… which sounds a lot like a compass.

I agree that you won't get an accurate bearing from the bearing screen but if you look at the satellite screen you will know where North is. The fact that the GPS has locked on to a bunch of satellite positions means that it knows where north is. It might not know which way your standing but why is that important? As long as I have a map, a distance to a waypoint (the GPS knows that) and can read the satellite screen to find the general direction, I don't have to be moving to know which direction to walk.

Explained very well here for those who are curious:

http://www.gpsreview.net/satellite-info-screen/

I think you made a good choice getting the newer version of the Etrex (Etrex 10) however, for the price difference, I would have recommended the Etrex 20. The feature set on the Etrex 20 is amazing! I've been using it for quite a few months now and can't believe what it can do. The fact that I can load my own custom map images as well as Garmin's Birdseye imagery makes the Etrex 20 an incredibly good value. I haven't once said "but I wish it did…", it seems to do it all.

[Bob Gross]

"Bob G., am I missing something?"

James, not that I can see.

If you set aside any possible digital compass feature, a GPS receiver cannot tell which way it is facing or pointing if it is stationary. That is the primary reason why a few of the newer receivers have a digital compass added on. As soon as it starts moving in some consistent direction, it can tell the direction of progress. Where this gets messy is at very low speeds, because it can't tell what is intentional progress and what is simply position "noise" and sitting at one point. So, each manufacturer has built in proprietary fudge factors for these small details.

If a military GPS receiver is in a jet doing Mach 2, you need lots of these fancy fudge factors working together, and the sequential position fix rate is very high. At Mach 2, a tiny jiggle is a big error distance. In ordinary civilian receivers, the fix rate is much slower. In one particular model that I use, the fix rate appears to be about twice per second. That's still way overkill for what a backpacker needs for a maximum speed of about five or ten miles per hour. I've seen some receivers that have been modified to slow the fix rate down to about once per ten seconds, and the primary reason is to preserve battery life. To get the good out of that, they had to figure out exactly which functions could go to sleep and which functions had to stay awake full time.

The very simple receivers such as the old Geko display some position numbers well, but the "map" display is just about zero. The newest receivers have very complex mapping displayed, but they use lots more battery power to drive it.

–B.G.–

[Bob Gross]

Mike W., "Reading the Satellite Info Screen" on the GPS Review web site says nothing at all about determining your facing direction when you have zero speed.

"…but if you look at the satellite screen you will know where North is."

Nope.

"The fact that the GPS has locked on to a bunch of satellite positions means that it knows where north is."

Nope. You are completely misinterpreting what it is displaying and what it means.

The Satellite Info Screen can tell you where the various GPS satellites are in the sky, but that doesn't do you any good for knowing your facing direction. I've been reading Garmin screens for 15 years.

–B.G.–

[Roger Caffin]

I'm with Bob on this.

Cheers

[Karl Gottshalk]

I just bought an E-Trex 20 for a new toy after having a Geko 201 for many years. My phone and camera also have a GPS. Sitting on my couch in the living room, it acquired 10 satellites within the first 2 minutes of turning it on for the first time, none of my other devices ever picked up any. When I have done an out and back hike in heavy woods both tracks coincide exactly, something I had not seen before with the Geko or phone.

I subscribed to their online maps, but find I am preferring the free ones at GPSFileDepot as they are easier to read and redraw faster. So far I am very pleased with this purchase.

As always, YMMV
Karl

[Jeff McWilliams]

Watch out for poor or no GPS reception from Android or other smart phones while in remote areas.

I've been geocaching in various parts of northern Michigan. A friend tried to user her Smartphone's GPS function while I used a Lowrance Endura GPS. She couldn't get a satellite fix while we were in remote areas, but my GPS worked just fine.

Yeah, it's an anecdotal report. Your mileage may vary based on make and model of phone, etc.

[Jeff McWilliams]

Bill wrote:

"As a civilian GPS accuracy is deliberately degraded from the Military Standard."

Are you referring to selective availability? That's been disabled since the Clinton administration.

[John Jensen]

I expect that at some point someone will do a phone a little more centered in GPS and battery life. It makes sense. We're a big enough market. Until then what manufacturers see as market "divisions" shape our choices. We suffer low phone battery life because makers think we prefer slim phones to 24 hour GPS life.

I was really happy with my old Etrex Legend (the blue one). The Etrex 20 seems a better more modern version. That said … I'm just not hiking places where I really feel I need a GPS. So, it will be map, compass, and occasionally Droid X for me, for now.

[Jerry Adams]

You don't need compass.

Start walking in what you think is the right direction.

Look at the track points on the map on the GPS.

If you're not going in the direction of the waypoint, adjust.

[John S.]

If that direction is off a cliff, up a bluff or into catclaw then you do need a compass.

[Mike M]

looks like the 10 is 5 oz vs 3 oz for the 301/401, little longer battery life, but I've used my 401 on week long trips and still have battery life left to spare

[Jerry Adams]

Whether you have GPS, conventional compass, or the sun – you need to look around and find a passable route – don't walk off cliff or whatever

With a conventional compass, if you're at a high area, and you see something you want to go to, you see what direction it is on the compass, and then you can keep going in the same direction even when you're in the forest and can't see it anymore

With a GPS, maybe you can locate the object you want to go to on the GPS map and then you can just look at your track on the GPS and if you're going in the wrong direction you'll quickly see it and you can adjust

Or, while you can see the object you want to go to from a high area, start walking towards it and look at your track on the GPS and you'll see which direction it is, then you can keep going in the same direction even when you go through forest where you can't see far away

I configure my GPS so the map always has North up. I hate it when the GPS trys to orient the map so it thinks up is the direction you're going, because that direction keeps changing so the map keeps rotating back and forth which makes me dizzy

My electronic compass is almost useless so I just turned it off – it also saves battery life I believe

[Mike W]

>> I've been reading Garmin screens for 15 years. <<

So have I, so what?

So for Roger and Bob, I will agree that if I do a cold start with my GPS and I haven't moved, then the GPS can't know where north is. This is a fact. I will also agree that if I was walking with my eyes closed and don't know which way I was walking then the satellite screen won't help me locate a bearing until I start moving again since I need to know my last direction of travel for the satellite screen to help with directions while stationary.

But if I have been moving and have stopped (which is what I think we are really discussing) then the satellite screen will show me which way is north and my previous direction of travel. It's a "feature" that you may not use or know about but none-the-less it's there.

The satellite page saves your last known direction of travel on the horizon circle on the satellite page and unless you are somehow disoriented and can't remember which way you were walking, then you can use this page to locate north. All I have to do is align the dot with my last known direction of travel and I will know which direction I was travelling and where north is (while I'm stationary). It's not the same as an electronic compass (which is handy if you are a geocacher that is spinning in circles looking for a cache) but it's a useful tool for the hiker that is on the move and occasionally stops to look at their map.

So to re-emphasize what I said in my initial post regarding the fact that a GPS is useless for locating your direction of travel while stopped, I will stick to my original statement which is "it's not entirely true".

[Bob Gross]

" "As a civilian GPS accuracy is deliberately degraded from the Military Standard." "

"Are you referring to selective availability? That's been disabled since the Clinton administration."

Jeff, this is something different.

All of the time, there are two signals present in the downlink. One is the civilian signal on 1.57 that you may be familiar with. The other is the military signal on 1.2, and it has higher precision, but it is encrypted. So, unless you are an authorized DoD user with a valid crypto code, you will never find the military signal. I've seen it, and it is scary.

–B.G.–

[Bob Gross]

"If you're not going in the direction of the waypoint, adjust."

Jerry, that's pretty much it, isn't it?

The real compass can become handy if your GPS receiver has a dead battery or total failure. Also, if you operate in places where the GPS signal can't reach, like in a deep ravine or a cave, or underwater.

–B.G.–

[Jerry Adams]

Yeah, you should have a manual compass in case the GPS dies.

I have a little cheap-o plastic compass.

And the wind speed vane on my ADC Wind. One of the blades is red. That one points North.

Neither is very accurate but good enough to keep you going generally in the same direction.

[Bob Gross]

"But if I have been moving and have stopped (which is what I think we are really discussing)…"

I don't believe that this distinction was ever made.

To do the test. Stand motionless in one spot and turn on your GPS receiver. Give it however long to lock up a position fix. Note the directions on the Satellite Information screen. Now, without moving off your spot, rotate your body around until you are facing some other arbitrary direction, say 90 to 180 degrees around. Now note the directions on the Satellite Information screen. How does the first screen view compare to the second screen view?

They are the same, since the GPS receiver still can't tell which way it was facing. It knows what might be in view in the sky and where those satellites are by direction, but it doesn't know which direction it is facing.

All of this changes when you add in the digital compass feature that some models have.

–B.G.–

[Mike W]

>> "But if I have been moving and have stopped (which is what I think we are really discussing)…"

I don't believe that this distinction was ever made. <<

By the simple fact that this is a backpacking forum, I think we can assume that we will be moving. I don't know about you Bob, but when I'm sitting in front of my computer, I don't need to turn on my GPS to find out which way is North.

I'm not looking for an argument, I just thought I'd mention a feature that many GPS users overlook. If you don't want to use this feature then don't.

[Bob Gross]

What some new GPS users will discover after a period of lots of use is that different GPS manufacturers have tweaked many of the small details of operation. The basic position fixing operation is cut and dried, but lots of the small details are not. An example is how the receiver treats a fixed position. If you are in a fixed position, how does the receiver really know that it is in a fixed position? If the velocity gets extremely close to 0.0 mph, then that is one indicator. However, even a fixed position will give a "snail crawl" track display due to the small errors of the system. How many feet is it allowed to seemingly crawl before it determines that it is not in a fixed position? Is it one foot, ten feet, or fifty feet? For years I used a receiver that had a Position Averaging Mode. Run it for four hours in one spot, and then it knew precisely where it was (not just about where it was).

Further, few manufacturers specify these kinds of small details for user operation. Those are considered to be trade secrets. Lots of these small techy details fall into the category of "heuristics." That means guesswork or maybe common sense. It would really help some users if the heuristics were spelled out. That way, they could know what the GPS receiver is thinking and guessing, and that could help the user to know when a GPS blunder is happening, and then what to do about it.

If the receiver is a so-called mapping receiver, should the display be forced to be North Up, or should it be Destination Up? What if there is no destination? There are just all kinds of techy details hidden in there, and it becomes great fun to try to unravel the secrets.

–B.G.–

[Mike W]

Well I certainly agree with you on that point Bob.

I'll sound a bit like Roger on this one because I have to say that many of the features are driven by marketing spin with a focus on creating sales rather than better GPS units.

The one that bugs me the most is related to the point we have been discussing (stationary location). This one really frustrates me because you may see sat nav systems in cars that show the satellite page and they include the location of the sun and moon on the page. So why does this bug me… because I have never seen this feature on a handheld unit. Why?… because that would allow me to align my GPS with the sun or moon and accurately use the GPS as a compass while stationary. Why don't the manufacturers offer this feature? Because they would lose sales of GPS's with electronic compasses, so I suspect you will never see the sun and moon position on a handheld unit even though it's easy to program in (in fact I suspect it's already programmed in but they don't allow you to access it).

It's also why they won't put replaceable batteries in their wrist watch units. That would interfere with the hiking GPS sales. They have to make sure we buy one for each of our hobbies… a GPS for Golf, Hiking and running… Oh, and for your car!

[Bob Gross]

"I have to say, I'll sound a bit like Roger on this one because I have to say that many of the features are driven by marketing spin with a focus on creating sales rather than better GPS units."

Oh, no argument on that.

Even dinky little sales and marketing departments know how to spin the features on GPS products. I know. I spent years there.

Often features are in there and advertised, but they have virtually zero practical function. They are in there just so that they can be advertised, and the competition doesn't have that feature. In other words, it looks good on paper.

The primary function of these features is to extract the maximum amount of cash from the user's wallet.

Part of the user problem is that they really don't understand exactly how GPS works (or doesn't work). They don't understand the practical limitations. They don't understand why they should not buy a 14-ounce solar charger to charge up their 8-ounce GPS receiver on the trail. A really good marketing department moves the user past the decisionmaking [should I buy this or not?] and moves them into the concept area [wouldn't this be cool?].

–B.G.–

[Stuart R]

However, even a fixed position will give a "snail crawl" track display due to the small errors of the system

The track that you get when the receiver is stationary is more like what you would expect from an inebriated spider. It really annoyed me that there was no option for me to specify "do not record track points if less than 0.x MPH", so I wrote an application to post-process an gpx file to remove such points.

I also discovered that the latest firmware update for the GPSr had increased the precision of the lat/lon degree coordinates in the gpx file to TEN decimal places! You may appreciate how ridiculous that is if I tell you that that 0.0000000001 degrees latitude is equivalent to 0.01 millimeters!

[Nathan Hays]

I noticed tracks on my iPhone 4S don't have elevation unless the app has built in topos. Tracks without elev suddenly get them when I upload to a server – presumably they combine lon-lat track data with a topo.

If this is true – I haven't found independent confirmation – then one should be careful about any elev data off the iPhone. The reason is that the x-y points are strongly affected by whether you are on a steep slope or not. The signal tends to get drawn in and up the hillside by the multipath reflections and ground plane conduction. If the x-y is off by even ten meters in such a case, it could easily place your elev way off since it derives the elev from a topo. Note also that the topos are not super-super accurate either.

A great example of this is when I cross the Golden Gate bridge – 250 feet over the water, but my GPX track from the phone has me at sea level.

When I look closely at iPhone tracks on Google Earth, I see they do not exactly follow the clearly visible trail I walked. I know GE is often off, but it is off by a fixed vector over a small enough area. I find that north and south slope tracks "suck up the hill" rather than being both off in the same direction. The hidden effect of this is again in elevation.

I use elevation info (along with fall line heading) when orienteering from a topo and I'm not sure if the distant peaks are what I think they are. I have found that my baro altimeter is more accurate than the iPhone elevation once I take into consideration weather variance (recal at known spots).

On a side note, my electronic altimeter, which is spec'd to 10%, reports exactly 10% shorter elevation change than was actually travelled. So if I recal at Road's End (5035) and hike up Copper Creek to the benchmark at Lower Tent (7825), the unit shows 7550 = 10% short of my known location. Just the opposite is true going down – it reports a net 2500 feet, ending up at the correct recal elevation. I sure wish the unit would take a correction factor input, but at least I can keep myself occupied with the math.

My GPS is an ancient Garmin eMap, so I wouldn't use it for any comparison with what may be available today. Has anyone else compared the elevations in the GPX files between smartphone and a dedicated GPS?

[Nathan Hays]

BTW, since long before I had ever heard of geocaching, I have been 'collecting' benchmarks. Somewhat informally in the dark years before GPS, and now electronically. What I do is find a BMxxxx entry on the topos, then hike to the spot and try to find the brass benchmark itself. Then I record a new waypoint in the GPS unit at that spot and name it according to its elevation.

Makes me want to return to some spots I have been but passed up or never found the benchmark.

[Author]

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