Yes--I'm familiar with the "close unit problem," where TU 492N/502E
comes out south of 488N/500E on a site grid, from datum corner UTMs.
3-5m accuracy means exactly that. Much better in locating sites on a
regional survey, and, especially, ensuring that you, or the next
archaeologist, are able to get back to that site (or, back to the place
where it was, before the construction took place), some years into the
future. Also, better for survey baselines. Blockage from dense
vegetation is not supposed to affect readings, but it does, another
thing not covered in the advertising. Still, having not been able to
find sites located by the map template method, it's a godsend. Hope the
satellites all stay up there.
D. Babson.
-----Original Message-----
From: HISTORICAL ARCHAEOLOGY [mailto:[log in to unmask]] On Behalf Of Lyle
E. Browning
Sent: Saturday, October 23, 2004 12:09 AM
To: [log in to unmask]
Subject: Re: Digital Recording
On Oct 22, 2004, at 11:07 PM, David Babson wrote:
> Can the Garmin unit provide UTMs?
Yes, both the Garmin 48 and the newer Garmin GPS 72 have UTM readout
capability. Check the Garmin website to make sure that the eTrex and
similar tiny units are so configured. For those on the Mac side of the
house, a cable and software can be had that will enable downloading and
plotting of coordinates at USGs Quad scale.
> I have been thinking of getting a GPS
> unit, one of these days--my primary use of GPS is to locate sites,
No problem getting a usable reading.
> test units,
Depending upon whether WAAS is enabled, it might not be able to
represent close units.
> STP transect baselines,
Should be able to, if it can keep the satellites in view. In dense
woods, losing a satellite set will produce data groups that are
internally consistent by group, but do not necessarily relate
accurately between groups.
>
When all's said and done, I would not be without one in the field. In
some terrain, where you are is a problem. I take a reading at the car
or create a waypoint at where I want to be and let it do the driving,
as it were.
Lyle Browning
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