Mounting Garmin 62 to rucksack

[PaulQ]

In Lyle's UNM, the SAR team members have their Gamin's mounted on their rucksack straps. I have looked around for how this is achieved. Are they using a slip case such as this one?

http://www.aboveandbeyond.co.uk/.Garmin-GPSMAP-62-Series-Slip-Case_753759968526.htm

This case doesn't seem to have a way of mounting it to your straps as far as I can see.

Any advice on the best way to do this would be appreciated.

Thanks
Paul

[Lyle Brotherton]

No easy answer here Paul.

I used the Krabs that come with the unit and affix them to my rucksack shoulder strap, but the lanyard that they come with is a little too long and they swing about. I have used elastic bands to secure them but was caught out when in the Arctic they simply snapped.

Anyone else tried more successful methods?

[PaulQ]

Thanks Lyle.

Glad to know its not just me who's struggling to mount it. It looks well done in all the photos though!

I have mounted my rolled up map case to the straps of my rucksack using split rings and shock cord with toggles - an idea I got from Bob on the Backpacking light web site, not had it on long but seems to work well. Maybe that slip case could be adapted using this method.  I'll have a bash at some stage and let you know.

[Lyle Brotherton]

I had a short 10km walked already planned for today so decided to test an idea I have had about carrying the 62 series and I tested carrying the 62 in my anorak hood, my trouser pocket, inside my rucksack and mounted on my rucksacks shoulder strap.

My thinking has been that the unit uses predictive ephemeris (Garmin call this HotFix, Delorme Synthetic Ephemeris and TomTom QuickGPSfix).

Predictive Ephemeris
This is where the unit downloads all of the data regarding the current location of satellites as well as estimates of future range and position of these satellites, Garmin’s algorithms will do this for 7 days, Delorme 2 days and TomTom 1 day.

The units use pretty sophisticated algorithms to mathematically extrapolate the current valid ephemeris data with regards to the ellipsoid orbits of the satellites, gravitational effects and the Earth’s oblate spheroid shape.

This is a big advantage as current ephemeris data has a use by time of 4 hours, after which the process must be repeated position reporting, so without it TTFF (time to first fix) can take up to 40 seconds if the unit is turned on more than 4 hours after the first recording, with predictive ephemeris is less than 5 seconds.

And the feature that interests me here is that the location data is more accurate as the unit can predict the range and position of individual satellites it cannot get a full signal from.

Results
Frankly disappointing, in that when inside my rucksack or trouser pocket the position it reported was consistently around 15m out.

In my hood 5m inaccurate and when mounted correctly within the 3m I would have expected.



If you look at the type Harewood Glen (on the east of the map) just underneath it to the left of the G is a building, The Old School House, 20m before I reached this building travelling north I switched from correct mounting to trouser pocketall the way up to Newark Castle (NE of map)



This image is of a close up of my path along the road past this building. You can see how accurate it was on my approach from the south, but afterwards it was rubbish.

Thoughts
1.   I did not leave the unit for enough time at the beginning of my journey stationary to collect all of the data.
2.   I had not calibrated my compass, I don’t know why this would make a difference but it was an error in my standard operating procedure (Sgt. Wilcox will love this!)
3.            The unit was sampling automatically and therefore smoothed out the curves.

[Lyle Brotherton]

I found the answer to my own question last weekend, whilst working with some great Lowland SAR Team members and training them touse the ubiquitous eTrex H.

'Was the unit was sampling automatically and therefore smoothed out the curves?.'

Set to Automatic, the receiver saves nodes around every 10m, at walking speed, then it does smooth, in other words remove nodes when you save it. To make your track more accuarate, simply set the sampling to more frequent in the Track Setup menu.

This whole exercise really reinforces with me just how good the old eTrex H is, because it is right back to basics and makes you think about what you are doing . As I have just clearly demonstrated, we all forget sometimes how do to this

[RobW]

Hi

At the risk of returning to the original subject...

I have used the Garmoin karabiner (http://www.amazon.co.uk/Garmin-010-10481-00-Carabiner-button-clip/dp/B00030F7I2/ref=sr_1_1?ie=UTF8&qid=1341260667&sr=8-1) and modified it to mount on my rucksacks. I cut the paracord and threaded through the webbing on the shoulder strap and 'glued' the ends together by melting with a lighter. For additional security I stitched a few turns on either side.

By securing via the cord the clip is flexible and doesn't restrict the shoulder strap and cause rubbing. I have been using this on both of my sacks for 18 months + and it has been chucked in car boots and on buses and roof racks, often wth GPS still attached and is unscathed.

I've put a photo on photobucket for those who are interested.

Cheers

Rob

[Lyle Brotherton]

Welcome aboard RobW

An ingenious solution and very effective. When climbing the Garmin 62 Karabiner mount is a nuisance, your solution eliminates this. Thanks 

[Callum]

Anyone seen anything as ingenious for the eTrex?

[ianj37]

I too was taken by the way the Garmin appears to attach to a rucksack strap and disappointed to find that it was more difficult than it looked!
Unfortunately when I looked on Amazon the clip suggested by Rob was out of stock for a few days. So, being a person of little patience the search was on for something else and a quick Google came up with the Garmin Backpack tether reduced at GlobalGPS to £12.50.



Essentially this is a velcro pad which attaches to a rucksack shoulder strap by 2 velco straps and is connected by cord to a velcro pad on a Garmin mount which clips firmly on to the mount on the back of the 62. So, if you're really into velco or, like me want to show that whilst you won't see 50 again you're not afraid of modern technology, or if you'd appreciate the initial bit of tension that knowing that all that is preventing your x hundred pound GPS crashing to the floor are 3 pieces of velcro can bring then this could be for you!

 

Took it out for a day on Kinder yesterday and I can report that it works really well, I'm delighted with it - never fell off and after a couple of goes getting the velcro pads (which you can only see out of the corner of your eye) aligned comes naturally. I also tried dropping the GPS (with a lot of soft grass underneath!) and the rucksack mount always held firm.

Issues encountered:

1) The straps that attach to the rucksack shoulder strap appear to be designed to go round all the shoulder strap but then the join is on the inside and I found this dug into my shoulder a little. On my rucksack it's easy to move it to a webbing strap on the front of the shoulder strap but then the velcro strap is too big and the GPS unit hangs forward a little.

   
 - to be honest not a big problem and easily fixed with a small piece of velcro but I have no idea whether this will withstand a bit of rain.

2) For me the cord is a little too short to hold the GPS at arms length.

3) It works so well it's easy to forget that it's there so when putting the rucksack down on rocks you have to remember to make sure the GPS isn't going to get scraped.

So another alternative mount for anyone interested.

Ian

[boogyman]

Glad to see that I am not the only one "struggling" with Garmin's satnav mounts 

But, besides securing the device to (eg) your rucksack, there's another characteristic that I am looking for: while on a hike, I use to detach my satnav regularly to actually "use it".

So I want to be able to detach and re-attach it while walking, preferably with one hand and without having to focus my attention on it. With Garmin's mounts for the eTrex HCx series that worked perfectly well. With their new mounting system it doesn't.