UKC

I'd like to get a GPS for general use in the hills. I've spent lots of time out and about without great map reading skills but staying within my limits. I'm not looking to suddenly disappear over the horizon with blind faith in a bit of hand held kit. That said, I now have my 5 yr old in tow which even on a simple walk has left me wishing I was an OS wizard (even though we've been fine!).

What I'm looking for is something to support my ropey map reading skills and something extremely reliable should we ever get in strife and need to give an accurate position.

I have GPS on my smartphone but it loses it's signal as often as it keeps it and the battery life is short when it's on. Basically I don't trust it and it's put me off just using the phone GPS function.

I've just upgraded my car sat nav and it's been an education in just how much improved systems can get - that they are not all the same when it comes to keeping or losing signal and usability.

Any advice welcome.

In reply to flopsicle: The Garmin eTrex are good enough for this I guess, come in different shapes and colors. It is (was?) possible to download openstreetmaps files and to use them on these. I bought one years ago in case I needed an emergency location device, but never really used it in the end...

As a side note, I would strongly recommend that you take a "course" for navigation skills. N ot necessarily from a pro, maybe you can find a friend who knows enough. But if you have no friend and £50 to invest in a GPS, I would rather invest them in a one-day course with a professional. It doesn't take a lot of time to learn the basics and you can practice on easy days. This is definitely a set of skills worth having. You can then impress your child, and tell him/her you have learned all these skills when you were captain in the southern seas/explorer in Patagonia/treasure hunter in New Guinea. Sorry for the lecture, but I really really think you would be happier with OS wizardry than shiny gadgets.

In reply to flopsicle: Hi, I have sent you an email. Get in touch if you want to take the advice above.

In reply to drolex:


Agreed. Not only that, but a 1m (10 figure) grid ref fix from a simple GPS receiver isn't a lot of good if you cannot relate it the the ground, and how to get out of where you are; you need to be able to read a map to understand where you are, where you want to go, and how to get there safely.

You could download a route and load it into a GPS receiver, and get it to guide you along the route, but you could get into real trouble if you do, and a map, and the ability to read it, is essential.

The OS have some fairly good teaching materials, which should cover the basics:

http://www.ordnancesurveyleisure.co.uk/leisure/map-reading-workshops.html
http://www.ordnancesurveyleisure.co.uk/leisure/docs/map-reading-booklet.pdf

or for younger readers:

http://www.ordnancesurveyleisure.co.uk/leisure/docs/easypeasy.pdf

These comments aren't in any way meant to be having a go at you.

If you do get a GPS, some kids do seem to love geocaching, and, if used with a map to plan routes between caches, this can be a fun way to learn to navigate, and to hunt 'treasure'.

GPS receivers come in all flavours, from simple ones that give just a grid ref, to ones that have full OS or other mapping, can plan routes, etc. I use a mapping GPS PDA that doesn't support routes, and use it as a 'live map'; it shows me where I am, but I still have to work out where to go, and how.

In reply to flopsicle:

I would be interested in recommendations for GPS devices that can last a long day (>10, up to 24 hours) in the hills on a single charge. My garmin 410 watch costs about £150 or so but lasts about 8 hours only, which is fine for running and probably for any walk a 5 year old could manage, but is not enough for whole-day outings.

Even with superb map reading skills, a GPS device is still great for finding out where you went, how fast you were, ascent etc. I love mine. It has not replaced use of a compass etc, but has added to the pleasure of having been out and about

In reply to mbh: My Etrex 20 has good battery life.

In reply to mbh:

Is it for navigating? Or for recording where you went?
If its the latter, the igotu logger would be ideal.
It's about the size of a single chunk from a Yorkie bar, and the battery can last weeks (depending on the recording freqency).
Maplin sell them for £40.

In reply to mbh:

The etrex Legend I have lasts well over 16 hours,( I use rechargeables) and there are some very high capacity rechargeable batteries available. ( OR just carry spare batteries)

I always do carry spares anyway, but rarely need them, so that perhaps the easy answer, and good practice.

In reply to flopsicle: The GPS on mobiles doesn't rely on a phone signal btw. They use the same satellite-based system as any GPS, and some even incorporate GLONAS now like dedicated top end GPS units. Some mobiles do have a default setting that means the phone signal is used to "assist" the GPS, but I've never seen the point of this, since it means when there's no signal the phone uses all its power, and a lot of time, trying to find one. Answer is just to go into your phone settings and turn that feature off. Then stick your phone in a waterproof bag and you've got a perfect back-up GPS. Just make sure the battery is charged, and turn it off until needed if you're going on a longer trip.

In reply to flopsicle: where in the uk can you go beyond your limits? Map reading isn't hard, just a logical process.

Could do with brushing up myself, where you based?

Nothing wrong with using a GPS, but it can make you lazy.

In reply to jonnylowes:

Depends on your limits don't it.


I've been through a few GPS units, two died and got warranty replaced (not as waterproof as the marketing would have you believe!).

Lately, I've been really liking GPS status android app (when I want UTM) and google earth. Awesome tech, but as you say - delicate and short of battery life.

Just got a Foretrex 401 (was talking about it in another thread). Really like it. It has no built in maps, but that's not the sorta feature I want as big screen is bulk and cost, and I think you should always carry a real map.

In reply to flopsicle:

Thanks for all the advice. I'm not looking for a GPS to replace map reading or to get out of it. I have friends that can show me the basics (some of which I have already) and I'm not looking to stop learning.

I want the GPS as back-up, augmentation and a confidence giver. When it was just me and adult friends I was content with the abilities I already have but now I have a 5 yr old in tow it feels different and anything that has the potential to make a difference feels worth it - like a bivvy bag, I wouldn't take it planning on kipping outside or not bother to get off the hills by nightfall, but it's light and no bother and has huge potential should I screw up, and people wiser than me do sometimes screw up.

I worked 4 mths 7 days a week in snowdonia leading treks in the hills (horseback) and I'm aware that mountain 'mist' ain't always just misty! I've known pretty solid map readers (who seem better than me - certainly ooodles more confident) climb the wrong peak! Coupled with my being highly respectful not just of me and mine's limbs but that MR have better ways to spend their time, I want to help myself.

If I feel I've done what I can to be belts and braces I'm far more likely to keep practising with maps - of which I have very very many and I think that it every bit as valuable as the help of friends etc.

So, for reliability, accuracy and battery life any other recommendations? I'll follow up the one's already made too.

In reply to flopsicle: Did I read a few days ago that some people doing the Welsh 3000s had to be rescued because they were relying on gps and the guy carrying it fell and smashed it? Difficult to understand how anyone doing this challenge would not have an intimate knowledge of Snowdonia!

In reply to altirando:

Possibly though there was the gentleman on the Glyderau who's GPS broke/ran out of batteries, had to be rescued because the map he had was for the scottish highlands.

In reply to flopsicle:

It's a bit like stupid deaths! I'm not sure a story or 2 of map loss would put me off wanting a map, likewise...

In reply to flopsicle:


In that case (i.e. you want to get a ref in an 'emergency', and hardly ever use the thing otherwise), you could do a lot worse than a second hand Garmin Etrex 10H or Geko 201. Or a GPS smartphone with an OSGB grid ref display app (turned off most of the time and stored in a waterproof container).

The thing to bear in mind with 'emergency' GPS is that you can't just turn them on and get an immediate fix; you'll need to wait for the cold start time for the receiver to find a satellite, collect the almanac, and then decide what satellites to look for, before being able to receive ranging data and compute a fix. 'Assisted-GPS', provided by smartphones, allows the almanac to be delivered by the phone network, thus avoiding the cold start time.

In reply to captain paranoia: Even if you've been abroad, the cold start time isn't the end of the world - 4 or 5 mins with a basic etrex, and usually much less than that if you are using it in a similar part of the country - fire up the gps when you are putting your boots on and then turn it off once it's cooking. Against that, you need to remember with a phone that pretty much any mountain valley will have little or no phone reception.

In reply to captain paranoia: Cold start time for my Etrx 20 is less that 5 mins. not the end of the world and what you loose on the swings you gain on the roundabouts - battery life when compared to Phone GPS

In reply to toad & highclimber:

Yes, I know that cold start isn't that big an issue. But you might be surprised at just how many people complain that their receiver won't give them an instant fix. All I was trying to do is explain why, and also explain what A-GPS does.

Since the almanac message repeat rate from a satellite is 12.5 minutes, if the receiver has an expired almanac, it can take at least this long to update. This can be reduced by using the multiple receiver channels in a modern GPS receiver to collate the almanac from a number of satellites, assuming the satellites the receiver picks to listen out for are visible...

In reply to captain paranoia: That's fair enough. I think my bigger concern is that phones really aren't up to the roughty-toughty upland life, either because of fragility or battery life, never mind the unreliability of signal for the 'phone bit.

In reply to toad:

Yeah, I agree.

Sorry, I just got really busy and didn't have chance to type a proper reply. Thanks again for the suggestions!

I thought it might be helpful to just list the things I imagine (as I haven't used one yet!) using the GPS for.

1. Increasing my confidence and getting feedback re map reading:
I feel a great sense of relief when I see a firm, un-mistakable landmark on a walk, confirmation that I have navigated accurately. When sitting down for a snack I want to use the sat nav to confirm position in the same way, mostly to boost my own confidence but also to be aware if something's wrong when I have a 5 yr old in tow. Waiting for a sat signal is no bother as nothing happens quickly with munchkin along anyway.

2. Fear of fog!:
With my little one with me I've lost my bottle and from being someone who has always been respectful and cautious of the hills, I'm now only tackling routes that are crowded. I've never forgotten the instant fogs in Snowdonia, GPS or no they would still scare me.(I mean the ones where your feet disappear from sight!.) I fully accept that a GPS has more psychological impact than realistic help but a back track function is something I had on horseback and used. Trek ponies have inbuilt sat navs! What I've always known is that without that, even on routes I did daily, I'm not sure I'd have got every one back.

3. If something has gone wrong:
I've always kind of run my own fire drills - mentally practised simple routines if stuff goes pear shaped. I'm the mum, we take a whistle, my daughter knows to stay with me and whistle/shout like hell! that's as far as it goes while she's 5! But if I was awake I feel more confident I could provide an exact location in the terms that help shares, of course a means of communication is another thing but I cannot see the logic in saying 'because you may not have a means to communicate there's no point in bettering what you would communicate'.

4. Sense of community:
I used to always have WD40 in my car as it hated the wet and I started no end of other people's cars in those years, mostly in heavy rain my spray got folk back on the road. What's mine is mine to share, for any of the above, for anyone if needed. That's a central part of rearing my kid too.

5. FUN!!:
Running with my phone GPS, stretching out to get the best MPH up and down hills in my local woods - then my heart would sink as it failed to record half the time - usually the half I really wanted it to! I'd love to be able to show my daughter a record of how far we went, how high, etc and (pure opinion) a recording is different from just saying it, I could say we went anywhere but a GPS is just different. Loading tracks up, Google earthin' it, plus little detours and ambles that it's impossible to remember.

I don't think any of that replaces a map, I am hoping it helps me boost my own confidence so that I practice more which will make a difference.

This thread has raised some questions for me and luckily I know a retired mountain rescue guy of many years experience. In addition to what's been said here I'm going to have a very open chat with him before investing.

In reply to flopsicle:


You need to understand the limitations of a GPS, especially in mountain environments. In particular, you need to be aware of the effects of multipath on the reported position. Multipath (reflections off large objects, such as cliffs or large buildings) can shift the reported position considerably, and no amount of WAAS/EGNOS correction will help, since they don't, and cannot address multipath. And, due to the constantly-changing satellite constellation, multipath errors won't be consistent on outward and backtrack paths...

I'm painting a bit of a bleak picture, perhaps, and one that you aren't guaranteed to encounter, but it's important for GNSS users to understand the limitations, just as it's important for map & compass users to understand their limitations. You cannot always rely on the GNSS fix to be correct, and you must know when it might not be trustworthy.

In case you think I'm some sort of Luddite, I'll point out that I've worked with GNSS systems for a number of years, both in GNSS applications, and developing the Galileo system.

In reply to captain paranoia: That's interesting. How much do you mean by 'considerably' ?

I'm just after a rough order of magnitude.

In reply to IPPurewater: I had a multipath error when teaching someone some basic GPS stuff. I was at Pont Y Cromlech and the device was saying I was nearly at the base of Flying buttress. It gradually got better as I moved around but it was predominantly at least 50m out until I relocated to a better venue.

In reply to captain paranoia:

True, this is a starting point and there's plenty to consider. Knowing what you know - do you see any use in having a GPS in fog, or would you even use it if you did?

I don't think any replies have been Luddite like, just there seemed to be a confusion re whether I was planning to abandon maps. I did feel a bit like I'd blasphemed initially, but I'm not miss super confident all skills, it takes me quite a while to get to a point where I consider a skill thoroughly mastered.

In reply to flopsicle: I use Satmap. Not the cheapest but it is an OS map and GPS in one. Yeah there are occasions where it is out by 50m or so but they are both rare and obvious from the map (showing you on the wrong side of a steam say)

Using a plain gps means transferring grid references to a map. Using a satmap or similar means having a map on the screen with you with a handy blue dot showing your position. You can still use your map reading skills and indeed often need to. It shows you where you are but not where you're going. I've taken bearings off the screen in the past in whiteout conditions, walked on the compass bearing while pacing distances all the while keeping an eye on the blue dot.

In reply to flopsicle:

flopsicle, I've got an older grey scale Garmin Vista I hardly use. hugely expensive when I got it a few years ago, half that price now but does have decent memory if you want to track yourself.

If you want to borrow it for a while you're welcome, dunno if the manual is still about though, although it'll be online. PM me if you're interested.

In reply to IPPurewater:


Since it depends on the terrain and the visibility of satellites, and the direct paths, it's hard to put a hard-and-fast figure on it, but highclimber's example is pretty good; it can be 50-100m.

Strictly, it's not multipath that's a problem (because multipath assumes that the direct signal does get to the receiver); the real problem is where the direct path is blocked, but a reflected signal arrives instead. Imagine you're in a steep valley between two vertical cliff faces, a hundred metres apart. The direct paths to the satellites might not be visible, but the vertical faces might reflect the signal back to you, so the path length is quite a bit longer than the direct path. Since the position fix is calculated by triangulating distances to the known satellite positions, you can be out by as much as the additional path length (if you're unlucky with the satellites you can see indirectly).

In such cases, it's likely that the solution will detect a high error, since the path lengths won't be consistent, so watch the DOP display which will give you an idea that the receiver thinks its solution is questionable; DOP=Dilution Of Precision, a unit-free 'goodness' measure.

I've also seen my receiver (which has a SiRFStarIII chipset) give static offsets from my known location (using clear landmarks), with no multipath reflectors nearby. I still have no idea what caused that, but it snapped back into place some time later (I'd power cycled the receiver, and removed the battery, but it was adamant I was somewhere else).

In reply to captain paranoia: Occasionally the military play around with it for exercises but this is usually in specified areas and advertised beforehand.

http://www.grough.co.uk/magazine/2012/09/21/powys-military-jamming-will-aff...

In reply to spearing05:

Yes, they do muck about with it, but not in places like the Ridgeway...