Garmin/eTrex Legend Cx

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Garmin eTrex Legend Cx
Description navigator
GNSS 12 channels
augmentation: waas;egnos
DOP: no
Memory Internal: (10.000 max logging). External: ? sdmicro.
Connectivity usb
Batteries 2*AA (32Hrs lifetime)
Emblem-question.svg addresses Emblem-question.svg points of interest
Emblem-question.svg mass storage mode Emblem-question.svg Waterproof
Website Produktseite official link
  • You can upgrade the supplied MicroSD card from the default 64Mb to more than 2Gb (firmware 3.1 needed to use maps greater than 2Gb). Daily track logs can be automatically saved to this card.
  • EGNOS capable, so good precision. Quoted 10-16 feet accuracy can be down to 6-9ft on occasion. The map screen is customisable so you can add an accuracy field to the top of the map for instant feedback as to whether you're recording garbage or not.
  • Good battery life, much longer on battery save mode.
  • Waterproof - Submersible to 1 m depth, rugged.
  • Quick first fix - 15 secs warm start, 45 secs from cold, 2 minutes for complete auto locate.
  • Satellite visibility screen means you can see immediately whether you've got a good lock if you're in an urban canyon.
  • From Firmware 2.7 to 3.3 there seems to be an issue with the "Lock to road" feature. If enabled, it sets the current position to the nearest road. If disabled, this should be not the case, but the behaviour is just weaker. This makes the device pretty much useless for OSM, since new measurements do not add any precision, but instead result in the exisiting roads to reappear in the log. This can even be dangerous if you use a copyrighted map on the device!. References: Lock on road in osm beginners guide; Garmin support, changelog; groundspeak forum thread;another groundspeak forum thread. If you use one of the mentioned firmware versions, please upgrade.
  • Doesn't do NMEA
  • Doesn't store number of satellites or HDOP or WAAS/EGNOS status in gpx file on SD-card
  • Stores position data also if there is no satellite fix
  • Doesn't allow to access waypoints in mass storage mode
  • the adhesive with which the circumferential rubber band is fixed to the unit seems to get smeary after 1-2 years. The rubber gets loose. Some people have got a replacement unit from garmin after filing an RMA. See also this german blog entry

Comes with only a USB port for communications, and works well with Windows. Mac OS X support was added by Garmin only recently. The latest version of GPSBabel+ steps in to provide support for Mac/Linux users. Also, the unit can be put into USB mass storage mode, so you can just grab the GPX files off the data card without installing any software, which is actually easy and efficient.

Extracting GPX logs

First, you need a relatively recent firmware (since August 2006) If your software version is older than 2.50 then you need to upgrade - see the Garmin website for instructions. Then ensure you're saving tracklogs to the onboard data card. Setup -> Tracklogs -> Setup -> Save to data card

To extract GPX tracklogs without bothering with GPSBAbel, Setup->Interface->USB mass storage while connected via USB to your PC or Mac - the data card will appear as a new drive or volume. Tracklogs can then be drag 'n dropped to your computer.


Approximately 180 GBP including VAT in May 2007 ( ; around 155 Eur in april 2010 (eTrex legend HCx at, Cx not available any more). Potential purchasers could consider alternatives of Venture Cx and Vista Cx.

Venture Cx appears to be identical technical specification to Legend Cx (March 2007, Garmin Website), but cheaper shop price (150 GBP from Packaged "extras" included in price differ between Legend Cx and Venture Cx, being USB data lead (essential for computer connectivity, but appears to be very standard computer lead), copy of MapSource (useful though not essential, is included with Garmin's commercial mapping software), small MicroSD card (but given how cheap these are now, arguably not worth much).

Vista Cx adds electronic compass and barometric altimeter to Legend. Barometer has its uses, particularly navigating in mountain areas if GPS signal lost (tree cover, deep valleys, etc), and as a pressure trend monitor (weather forecasting). Probably not a useful upgrade for a road and lowland footpath navigation device.

specification despcription
Display 256 level color TFT ( 176 x 220 pixels )
Display size 3.3 x 4.3 cm (1.3" x 1.7")
Interface USB
Slot microSD
Dimensions (W x H x D) 10.7 x 5.6 x 3.0 cm (4.2" x 2.2" x 1.2")
Weight 5.5 oz (156 g) with batteries
Battery 2 x AA / 32 hours
Ships with eTrex Legend Cx, 64 MB microSD card, Database: Marine Point Database, Basemap, MapSource Trip & Waypoint Manager, USB cable, Wrist strap, Owner's manual & Quick reference guide



  1. eTrex® Legend Cx - specifications