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Paul ChristoffelGuest
Can anyone recommend a good GPS and a place to buy it?
I’m looking for something basic that will tell me where I am on the map on the (hopefully) rare occasions that may be necessary. I’ve seen someone use a GPS to good effect for this purpose before. Or should I be looking for something more sophisticated?
The most basic models don’t seem to have an altimeter. Is that a problem?
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RaymondGuest
Check out trademe.co.nz – heaps of good deals. Garmin etrek, 12xl, or magellan models work well. The Silva models claim to be the best in dense bush, but I have never used one. They all have 12 channel receivers so it should not make too much difference. The more expensive models tend to have greater memory capacity for stroring waypoints, etc. which you don’t really need.
Some have both barometric altimeters and use 3d positioning from satellites. You don’t need both unless you cannot get an accurate fix.
The mapshop on Vivian St sells GPSs, but also checkout mapworld in ChCh – they’re online and may do a better deal. Garmin.com has all the model specs, etc.
I have found my Garmin 12XL to be extremely accurate to within +/- 3-4 metres.
If you get the appropriate map software for the GPS you can plot your trip before you go and use the GPS to calculate distance, ETAs, etc. This was extremely useful in the Raukumaras 3 years ago, especially trying to find the track start marked by a toitoi bush.
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Paul ChristoffelGuest
The Mapshop only have Garmin. At the most basic level they do both the eTrex and the Geko 101. The Geko is very light and takes AAA batteries. This lowers the battery life but presumably that’s only a problem if you want to run the thing for extended periods. I’m not sure if there are any other significant differences between them as the techno language is a bit perplexing.
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Grant NewtonGuest
Paul,
I looked into GPS recently and found buying from overseas to be significantly cheaper. I haven’t yet purchased one, but was considering the Gecko 301 (includes altimeter, barometer & compass).
Generally the Garmin are the smallest – seems the Gecko range are very similar to their eTrex, but smaller & lighter. Here is a link to a site that will supply to NZ – some suppliers look like they have geographical restrictions of where they can sell to – probably to protect local retailers?
http://www.gpscentral.ca/products/garmin/geko.htm
These guys charge $275 Canadian for the Gecko 301, but the p&p is huge …. still seems cheaper that $669 via Map Shop or Dick Smiths. They also charge $130 for Gecko 101 (in NZ they are about $349-399).
Cheers
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RaymondGuest
The problem with smaller batteries (any in fact) is that in colder weather – where you’re likely to be using them, they lose power quickly. There’s a Garmin 12Xl which I have on trademe for $450: waterproof…Retail is about $900.
I’d recommend it. With Garmin you can use the Worldmap software to plan trips, etc. and link to the topomap software. Well worth it.
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RaymondGuest
That’s not me selling the GPS on trademe, rather I have a Garmin 12XL!
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Allan MacGuest
What about trying to get a GPS from rei.com?
watch the freight costs though…
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Don GoodhueGuest
Some thoughts on GPS:
As with the map and compass GPS is an aid to navigation. Without a map, either paper or electronic the information provided by GPS is meaningless. As with the compass, to be competent and confident with GPS you need to be on top of your map reading.
I would not get too hung-up on accuracies of 3 – 4m etc. A GPS will state an accuracy based on the quality of information it is receiving. ie: signal quality etc. Accuracy is relative to what you are referencing it to. ie: the accuracy of the map. When referring to the 1:50000 Topomap series, the accuracy of various information on the maps vary greatly, depending on the source data used to compile the map. For instance, roads are generally very accurate, tracks can be seriously out of position. My view is that if we consider Topo maps to be accurate to within say 20m, then without checking your GPS against a point of known survey accuracy, for all practical purposes +/- 20m is all that matters.
Electronic maps (for NZ at least) don’t really improve this as most of the data they are compiled from data is digitised from the 1:50000 maps.
All GPS units will give raw information – the difference will be in the “bells and whistles” added on. Think about what you want to use a GPS for as this may determine how may of these extra features you need. If the principle use will be for when all else fails, the Garmin eTrex may be all you need. I used one in Fiordland and found although not having the functions of the more expensive units, provided all of the essential information. Was easy to use one handed but was tough on batteries when not in the “battery save” mode. I found the compass heading function cumbersome and would use a compass for this instead (the GPS needs to be moving to resolve heading between sucsessive fixs). The eTrex gives satellite derived elevation. Consider carrying spare and emergeny sets of batteries. Raymonds point regarding temperature is very valid.
Perhaps the most important thing to remember with GPS is that the information it can provide you is only as good as you are able to understand it and apply it. GPS will work out distances and bearings very accurately but remember that these are as the crow flies.
There are a few technical things about GPS while not essential to know, having an understanding of which will give you more confidence with it and become relevant if you use it with different types of maps, both in NZ and overseas. I can provide more in this area for anyone who wants to follow this up.
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John SaundersGuest
I’ve been using the Garmin eTrex for three years now, and to my mind, the major advantage is in knowing exactly where you are on a summit ridge in the Tararuas, particularly in white-out conditions and gale-force winds. Inevitably you’re quite buggered, and you’re hanging out for that dodgy turn-off to Anderson Memorial, or those illusive Bivs at McGregor or Arete. Knowing your exact position gives you peace of mind.
I only use the numbers. To my mind the other features (ie waypoints) are of little use in New Zealand’s rugged terrain. I back up the GPS with a custom map, which I get laminated. Essentially, I scan the section of topo map I need on to A4, then I run a fine pen over those lines of latitude and longtitude, to make them a little heavier. I also write in the numbers at the end of each line, at the edge. That way it’s quite easy to convert the GPS readout numbers into your exact position on the map, and from there it’s your basic map & compass navigation. I find set of lithium AA batteries will last as long as you need (at least a week) so that’s not an issue. Often you won’t get enough satellites in range when you’re in a gorge, or under a dense canopy, but you just keep going until it opens up. A couple of other points; the error factor can be upwards of 50m and the readout numbers are quite small, and can be hard to read. Otherwise, they’re great, I wouldn’t go on the tops without mine. -
Paul ChristoffelGuest
Thanks for all the advice folks. I now have a Garmin Geko 201 bought off the internet. I’ve had a bit of a play – it looks like learning to convert the numbers into an exact map position will take a bit of practice.
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