(Now) I Know (Where I'm Going) Our Kid

Every few years over the last decade or so I have considered getting a GPS and/or SatNav unit, but after spending a while investigating the options my interest has always petered out. Part of me thinks that a GPS is unnecessary and if you know what you're doing a decent map should suffice. Indeed, I have managed to complete my round of the Munros without recourse to such electronic gadgets.

But that was before Google Earth. Having spent some time trying to remember the exact routes of all my Munro walks and recreate them in Google Earth as KML files I have come round to thinking, not what a useful aid to navigation a GPS would be, but what a lot of time it would save me if I could just dump a GPS track log and generate KML files from that. It would also be a positive boon in geotagging photos. In theory you can simply synchronise your digital camera's clock to the GPS before you set out on a walk (or take a photo of the GPS clock screen and sort out any time differential later) and then use the GPS track log to determine where you were when any particular photo was taken. Certainly beats messing around trying to place photos on your Flickr map after the event.

The path to actually getting a GPS started when I was casually leafing through a flier from Maplin there was a product on it called a GPS Travel Tracker. It was £40 and promised to "record and trace your journey using GPS technology". Caroline suggested I could get one for my upcoming birthday. It was interesting, but didn't appear to have any sort of display. What use is a GPS if it can't actually tell you where you are? I found Maplin were selling a similar model with a display for £70 (Holux GPSport 245), but it looked like it would only give your location as latitude/longitude - which might be quite useful if I was an 18th century mariner, but not so handy for using with my collection of OS maps.

For only £10 more I could get a Garmin eTrex H - the same model that I'd used in Norway to verify our location on our snowshoeing trek. Admittedly it was somewhat larger, but it can report positions on OS and WGS-84 maps, it can also do waypoints and routes, and I can vouch for its operability whilst wearing gloves in a blizzard.

My further investigations on Garmin handheld GPS units revealed that the units I had been looking at 6 years ago (such as the Geko 201) were still available, but now slightly cheaper. The development of the handheld GPS appeared to have followed two distinct paths. Firstly the handheld form factor has been retained, but screens have got bigger, become colour (and touch sensitive in some cases), maps from internal memory or SD cards can be displayed, allowing turn-by-turn navigation functionality like SatNavs. Some of them have even got cameras in. And they can cost several hundred pounds.

Meanwhile the smaller form factor, which started with the Foretrex wrist mounted series, has turned into the Forerunner series, which have finally shrunk down to watch size, and contain all sorts of functionality aimed at avid runners. But after having downloaded and read some of the manuals it wasn't clear that you could actually get a useful map grid reference out of them. So, in spite of their small form factor, they may not be that useful to me after all.

I decided I should get all an all-singing all-dancing handheld that could do everything I might possibly ask of it. I'd be able to use it for navigation on the hill, and as a SatNav in the car.

The next morning I awoke realising that everything I had decided the previous day was rubbish. What I needed was a small, light device that wouldn't be too much hassle to take with me anywhere (so I can use it's data for geotagging photos). It should be waterproof and have a display that can tell me where I am on a map, and I should be able get the data off it and on to my MacBook. That was about it. I decided if I wanted any more I could buy a separate SatNav system, which would have the added advantage that Caroline would be able to use the SatNav to meet me with the car at the end of a walk, while I had the GPS with me.

So, I settled on the Foretrex series, which I first looked at in 2005 and are still available. They are a wrist mounted version of the larger Garmin handheld GPS's and weigh 78g and are waterproof. The choice is between the 101 model (which takes 2 AAA batteries) and the 201 model (which has an internal Li-ion battery and comes with a integrated charger/serial data cable cradle, is a slightly different colour). The 201 is £20 more, but by the time you've added in the cost of a data cable and some batteries to the 101 they are almost the same price.

The major drawback with both units is that they come with a serial interface, which even when it was introduced was clearly a technology that had got a bit long in the tooth. But a bit of Googling led me to believe I could get a serial/USB converter cable for a few quid (or £34 if you buy it direct from Garmin), that would let me connect the device to my MacBook over USB. (This post has got quite long enough, so the serial/USB story will be a different post).

So, I plumped for the 101 as it has replaceable batteries. Although the 201 is a completely sealed unit - and so is probably more waterproof - I have a few qualms about how well the internal Li-ion will cope in a few years as they do deteriorate over time with use. With the 101 I can just bung in new batteries as I need, and if I end up going on a multi-day trek I can carry enough spare batteries to last for the entire time.

I ordered the unit from Amazon (£89), along with a data cable (£11) and a serial/USB converter cable (£5). I shall write up my experiences of using it with my MacBook for logging routes and geotagging photos in a separate post.

Interestingly, as I write this, Garmin seem to have updated the Foretrex line with some new models. The 301 and 401, which seem much the same as the 101/201, except the package is slightly narrower, the units have a more up-to-date GPS receiver, have slightly longer running times on a pair of AAA batteries and sport a USB connection. The 401 model has an electronic compass and a barometric altimeter. They are due to be available in Q3 2009, pricing is to be announced.

Update 2009-07-16: Amazon now has the Foretrex 301 and 401 units available for pre-order (due on the 20th July 2009), priced at £170 and £200 respectively.

Oh, for the uninitiated, the title of the post refers to The Shirehorses spoof of The Seahorses "Love Is The Law". For those that have been missing Mark & Lard since their last Radio 1 show five years ago, there is plenty of their material on YouTube.