Harbin Geologic Compass DQL-2A Aluminum alloy theodolite

Harbin Geologic Compass DQL-2A Aluminum alloy theodolite
- Pengiriman 6-15 hari
The instrument is to use a magnetic objects (that is, the needle), pointed out the direction of the magnetic meridian characteristics with the reading of the dial ring, can determine the target relative to the direction of the magnetic meridian. According to the two selected points (or a known point), the position of another unknown target can be detected.
[Specifications]:
Damping time of needle : 30-60s
Dial scale : 1
Precision of circle air level : 30 5/2mm(20 degree centigrade)
List of items:
A geological compass
A holster
An English manual
Product details:
Length : 77.5mm
Height : 20mm
Width : 66mm
Package details:
Length :130mm
Height : 100mm
Width : 80mm
VWK : 0.21kg(length*width*height/5000)
[Net weight]:249G
Magnetic Declination:
Magnetic declination, sometimes called magnetic variation, is the angle between magnetic north and true north. Declination is considered positive east of true north and negative when west.
For more information, please see : ngdc.noaa
If the compass needle points east or west of the true north, the offset is called east or west declination, respectively. The standard is to use the magnetic north (MN) as a reference for declination, even in the southern hemisphere.
For more information, please see : Geology in the Field by Robert R. Compton (Jul 1985)
Estimated Value of Magnetic Declination:
Declination is calculated using the current World Magnetic Model (WMM) or the International Geomagnetic Reference Field
TOOL152440