Subscribe Contribute Advertise Facebook Twitter Instagram Forums Newsletter

Smaller Lighter High-performance GPS Units (Outdoor Retailer Summer Market 2006)

Get Used to Smaller Lighter High-performance GPS units with limited navigation features

Print Jump to Reader Comments

by Alan Dixon | 2006-08-10 03:00:00-06

Get Used to Smaller Lighter High-performance GPS Units
but With Fewer Navigational Functions

Smaller Lighter High-performance GPS units - 1
The new generation of “performance measurement GPS” units have exceptional electronics and GPS performance. They are small, light and wearable but have minimal navigation functions. Left: the Garmin Edge 305, actually a bike unit but similar in weight and smaller than a Geko- it should work for a handheld backpacking GPS. Right: the wrist-wearable Garmin Forerunner 305. Both have barometric altimeters and heart rate monitors.

GPS manufacturers continue to focus their innovation and marketing in two areas,

1) Large-screened mapping units with full navigational functions [eg. the Garmin GPSMAP 60 and 76 series] around 8 oz, and

2) Small “performance measurement GPS”, usually wearable, but with small screens, no mapping capabilities and minimal navigational functions [Suunto X9i, Garmin Fore Runner 205 and 305; and Edge 205 and 305] around 3 oz

Why is this important to lightweight backpacking? Well, our core lightweight, navigationally focused units are languishing in the technological dust. The Geko 101 is discontinued and who knows how long until the Geko 201 and 301 fall into the tar pit of extinction? Neither the Geko or the eTrex units are slated to have the newest SiRF III GPS Engine. If you want to a good GPS fix in tree cover or in a tight canyon, you need SiRF III GPS or a similar digital GPS signal processor. [The new digital processing of the SiRF chipset has many thousands of times more signal processing power than traditional 12 channel analog GPS receivers. This means amazing performance like full time GPS tracking in a deep canyon of redwood trees.]

I’m deeply disappointed that improved mapping and GPS performance will not make it into the e-Trex and Geko series. Even just some better navigational features into the Forerunner or Edge series would be nice. Garmin are you listening?

While I laud the improvements to the larger mapping units (I use a Garmin 76CSx for my kayaking expeditions and love it to pieces), at almost 8 oz I wouldn’t consider them for a backpacking trip.

For the time being if I want the latest and greatest in lightweight GPS electronics for backpacking I need to make peace with the limited navigational features of the new small performance measurement GPS (SPM-GPS) like the Garmin Fore Runner 305.

Over the next few months I will be testing the applicability of small performance measurement GPS to lightweight backpacking. Hopefully we can come up with a How To/Tips and Tricks piece to use SPM-GPS for lightweight backpacking.

 - 2
New SPM-GPS units have tight integration with performance analysis software and electronic mapping like Google Earth. Example above is Garmin Training Center™ software. Below is the web-based application Motion Based™ that integrates with Edge and Forerunner data for performance tracking and mapping.

Advantages of small performance measurement GPS (SPM-GPS)

  • Sophisticated digital GPS circuitry captures weak signals in difficult reception areas like tree cover and narrow canyons or a combination of both!
  • Small wearable size (or in the case of the Garmin Edge small and mountable)
  • Potentially lighter weights (currently the same weight as the lightest units)
  • Tight integration with performance analysis software and with electronic mapping like Google Earth
  • Rechargeable batteries
  • Many monitor heart rate

Smaller Lighter High-performance GPS units - 3
Web-based application, Motion Based™, that integrates with Edge and Forerunner data for performance tracking and mapping.

Disadvantages of small performance measurement GPS (SPM-GPS)

  • Limited navigational functions (usually just 50-100 waypoints)
  • No mapping
  • Limited Battery life (non-field replaceable batteries = approx 10 hours) although there are ways to recharge these units in the field with user-hack battery packs attached to a micro-USB cable
  • Even smaller screens

How to deal with the limited navigation features SPM-GPS

  • Even though SPM-GPS data transfer definitions aren’t available in most mapping software like Nat Geo Topo! theoretically data transfer a should work by selecting a basic GPS unit like a Garmin 201 (National Geo Topo! already has a definition for the Suunto X9 units)
  • Also to transfer data you’ll need to load a USB/GPS driver
  • In lieu of on-screen GPS mapping, use custom printed maps with waypoint labels and download the waypoints to your SPM-GPS. For more info on this refer to Backpacking Light’s article Guide to Selecting and Using Ultralight GPS Systems


"Smaller Lighter High-performance GPS Units (Outdoor Retailer Summer Market 2006)," by Alan Dixon. (ISSN 1537-0364)., 2006-08-10 03:00:00-06.


Reader Comments

You must login to post comments.

New Visitors: Create a new account
Remember my login info.

Smaller Lighter High-performance GPS Units (Outdoor Retailer Summer Market 2006)
Display Avatars
Sort By:
Ryan Jordan
(ryan) - BPL Staff - MLife

Locale: Greater Yellowstone
Smaller Lighter High-performance GPS Units (Outdoor Retailer Summer Market 2006) on 08/11/2006 00:31:07 MDT Print View

Companion forum thread to:

Smaller Lighter High-performance GPS Units (Outdoor Retailer Summer Market 2006)

Dan Healy

Locale: Queensland
lightweight GPS on 08/11/2006 07:38:54 MDT Print View

At the end of the day the major use for most of us is get a lat/long at times when we need a bit of a hint… so while mapping and waypoints are good they are not the generally the reason we take a GPS. So a light weight ‘position fixer’ would be welcome…

Tony Burnett
(tlbj6142) - F

Locale: OH--IO
waypoints nice, but not needed... on 08/11/2006 10:18:44 MDT Print View

I agree with the above post. Everytime I have used my GPS it was to tell me "where am I now" (UTM). The map/compass do the rest.

Though I guess a few waypoints (20-50) would be nice in order to note good campsites, etc.

Phil Barton
(flyfast) - MLife

Locale: Oklahoma
re: waypoints nice, but not needed... on 08/12/2006 14:53:45 MDT Print View

Ditto. I've been very pleased with the capabilities of my Geko 301. But the addition of the SiRF III GPS Engine with the ability to fix a position under tree cover or in a canyon would be great.

Tom Casperite
(tcasperite) - F
Compatability with Topo. on 10/04/2006 15:53:26 MDT Print View

Just in case anyone was contiplating purchasing one of these units. I can let you know they are compatable with NG Topo. Above Ryan states with would work theoretically, but I had no problems with my Forerunner 205. The only issue I have is with some of the navigational features. It will not compute how far you are away from a selected waypoint, you have to look on the map and determine this using the scale at the bottom of the screen. I also found no way for the unit to quote you your exact location's coordinates. You can only navigate to/from waypoints. If anyone knows if this is possible please let me know, it is killing me. I have found that I can make a grid of waypoints on my map and judge where I by viewing which waypoint on the grid is closest. Very annoying, but these are the comprimises we make to lighten our load. This unit does aquire a great fix in a short period of time. Perfect for canyons, or the mostly tree covered NE.

Michael Davis
(mad777) - F

Locale: South Florida
SiRF III on 10/31/2006 18:57:51 MST Print View

Now that I recently upgraded to the new SiRF III chip, I cannot live without it.

Keep in mind that I hike in the east under almost total unbroken tree canopy.

This chip never looses it's constant fix (Garmin 60CSx). My old GPS (Garmin Etrex Summit) was lucky to give me a few fixes per day!

Mike Barney
(eaglemb) - F

Locale: AZ, the Great Southwest!
Re: SiRF III on 10/31/2006 19:11:21 MST Print View

I also got a Garmin with the SiRF III (GPSMap 76csx) earlier this year. The performance with the SiRF III is noticable and very impressive. We used it at Philmont and other places this year and never lost sat lock, in canyons, canopys and even under bridges, while others (including other Garmins) did. There was a problem with tunnels on the altitude getting wiped out, but they fixed that with a recent SW upgrade.

Happy Halloween!

paul johnson
(pj) - F

Locale: LazyBoy in my Den - miss the forest
Re: SiRF III on 10/31/2006 21:03:47 MST Print View

Hiking in the New England, i no longer use my For-eTrex. It's essentially worthless while on the trail due to the tree cover.

Best use is if i happen to pop out from under the trees on the top of some rocky outcropping. Then, i can turn it on and get a fix. Generally, i no longer carry it due to its poor performance. Of course, the batteries last a lot longer this way, but the TrakBack (BackTrak feature???) can't be used too effectively in this fashion if i choose to venture off-trail.

Thanks for the recommendations on the units with the SIRF III chip. Guess i'll have to shell out some more $$$ and give a different model a try.

Edited by pj on 10/31/2006 21:04:35 MST.

John S.
(jshann) - F
Re: Smaller Lighter High-performance GPS Units (Outdoor Retailer Summer Market 2006) on 11/01/2006 11:14:26 MST Print View

If/when Alan does an update after he has used these units, please let us know what we cannot do with the new units that we could do with the geko/foretrex series.

Doug Evans
(DougEvans) - F
Re: Smaller Lighter High-performance GPS Units (Outdoor Retailer Summer Market 2006) on 12/06/2006 09:56:31 MST Print View

You can get (almost) the same performance from your older unit by adding an exteral antenna...

IT's a bit of a hassle over the self contained unit, but a bit of rigging to place the antenna on top of your pack yeilds excellent results - including WAAS correction. Waas was imposible to receive here without the antenna - now I always get it.

paul johnson
(pj) - F

Locale: LazyBoy in my Den - miss the forest
Re: Re: Smaller Lighter High-performance GPS Units (Outdoor Retailer Summer Market 2006) on 12/06/2006 10:39:07 MST Print View

i've long thought about an external antenna, but i don't belive, please correct me if i'm wrong, that the Fore-trex 101 doesn't have an external antenna jack.

I don't mind opening it and modifying it if such is possible. If one isn't ready made for it, i'd need to consult with a good RF engineer (i'm certainly not up to the task alone) to get the job done right.