On 11/26/13 8:33 AM, Volker Schmidt wrote:
I also have used an old etrex HCx and a new
etrex 20. Both are good at the job. Battery
life is good (full day with rechargeable
batteries at 1 sec sampling). Resolution is
good (down to 1 meter with good satellite
visibility), especially with the newer model.
Position reproducibility is also good (down to
2 meters with the etrex 20). They work for
hours under pouring rain.
OSM maps in the US are of different levels of
quality. When I last mapped on the CA west
coast (Big Sur, where else?) I noted loads of
non-existing roads still there from the old
Tiger import.
On 11/26/13 8:52 AM, Richard Welty wrote:
the eTrex units seem to be much more accurate than the entry level
auto units from Garmin. i'm intrigued though, by Martin's description
of the 60CSx (which appears to have been replaced in the Garmin lineup
by the 62CS). if the good tracks are on the microSD card then that
means you can minimize cycles on the mini-USB port, as you can
remove the microSD and use an external reader. this should lead to
a longer useful life for the unit (yes, i'm really fed up with having
two dead Nuvis because of busted mini USB ports).
big country, not enough mappers in the right places, we're working on it.
I also use a Garmin 60CSx and would recommend the
62CS as a currently available replacement. If
you get one, I find that "every five seconds" is
sufficient for hiking-speed track point refresh.
Also, be especially careful opening and closing
the battery compartment: always twist the
thumb-clasp from "noon to 3" when opening, and "3
to noon" when closing (gingerly, metal on the
pins is soft, plastic on the case body is softer).
The accuracy of this 12-channel GPS receiver is
excellent: with a wide sky view I often get 4 or
3 meters of accuracy, and once got 2 meters. But
even better, in very dense tree cover (hiking in
Big Sur with lots of tall redwoods so the sky is
almost obscured) this unit still gets a usable
signal. Weak, yes, less accurate (maybe 15
meters under these conditions), yes. But try
that with a lesser unit and you'll simply get no
lock on enough satellites to fix your location,
let alone generate an accurate track. 15 meters
in deep woods is usually "good enough to find the
trail!"
The unit is waterproof (though doesn't float),
rugged to a modest degree (I once slammed it into
a rock face lanyarded against my chest while
belaying, with no damage or scratches to its nice
sapphire glass), has a compass and altimeter that
are actually useful, uses USB rather nicely (be
gentle plugging and unplugging a cable to give
the jack a long life) and sips batteries: I get
14 to 20 hours from a pair of solar charged
rechargeable NiMH AA cells. The ability to swap
microSD cards with OSM data provided by
DaveH/Lambertus is awesome: this feature alone
makes Garmin an almost must-have for OSM users.
For the software inclined, you can also use
mkgmap and "roll your own" maps from OSM data.
The buttons on my 60CSx have held up for almost
seven years of tough use, the interface is
straightforward and fairly complete, and Windows
and Mac machines are both supported well enough
to complete just about any data task. The 60CSx
(no longer available new, you might find someone
willing to sell one after-market) does suffer
from only being able to use one gmapsupp.img
(Garmin-format map file) on a microSD card at a
time (the 60CSx can't use microSD cards greater
than 4 GB capacity), but I understand the 62CS
doesn't suffer from this: bring on multiple maps
on super-dense card chips! Nice to be able to
select one mapset vs. another from the rocker
buttons on the unit, with no card swap, USB cable
mount, or desktop machine required (except to do
the copy/upload to the card in the first place).
The Molex metal bracket to mount the microSD card
is hard to figure out how to slide up and down
with your fingernail, be careful until you get
the knack of it, or you'll get a "card didn't
mount at boot" error (and no logging there, if
you turned on that feature).
Volker, in the last year, I have been busy
hiking, mapping and updating national forest and
wilderness areas in and around Big Sur (the whole
of Monterey County, or MoCo, actually). Not only
did another prolific mapper and I complete a
careful import (Farm Mapping Project from State
of California data), AND I uploaded the United
States Forest Service boundaries of Los Padres
National Forest, Ventana and Silver Peak
Wildernesses, I also cleaned up most of the
erroneous TIGER roads (as residential, most are
rural dirt tracks) by painstakingly comparing
them with Bing imagery. As Monterey County is
more than 2/3 the size of the state of
Connecticut, nearly 10,000 square kilometers,
this was no small task! OK, MoCo is far from
"done," but it is MUCH better than it was a year
ago.
Yes, we have a big country, but one road, café,
bike route and restroom at a time, OSM builds it
nicely.
SteveA
California
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