9.5 Compass Mode -
Magnetic Declination
9.4 Compass Mode -
Applications of the Compass Display and Backward Bearing
9.6 Compass Mode -
Magnetic Declination Compensation
What is Magnetic Declination
The angular difference between Magnetic North Pole
and True North Pole is called magnetic declination. Its
amount (degrees and minutes) and direction (easterly
and westerly) depend on where you are in the world.
The XG-30 also includes a setting for Magnetic
Declination compensation. Check the chapter 9.6 and
9.10 for more detail on how to compensate Magnetic
Declination.
Magnetic Declination Information
Most topographic maps include a small arrow which
shown magnetic north pole and or the magnetic
declination information.
This manual also includes the magnetic declination for
some cities in chapter 9.7.
For the city which does not include in this manual,
please refer to the below online resource:
http://www.geolab.nrcan.gc.ca/geomag/mirp_e.shtml
http://www.ngdc.noaa.gov/seg/geomag/jsp/struts/calcD
eclination
+
The Magnetic North Pole which is slightly different from
the True North Pole.
+
The XG-30, like most magnetic compass, points to the
Magnetic North Pole. On the contrary, everything
measure from a map is related to the True North Pole.
+
+
For serious compass user or whom intends to perform
accurate navigation, the XG-30 must be adjusted for
magnetic declination.
+
+
+
+
+
+
Check the position by Backward Bearing
Spot two distant identifiable landmarks such as
mountains, light-house and building from your
current position. Let's use mountains A and B as in
the example.
Check out the backward bearing direction of
mountains A and B from your current position: 135
from mountain A and 270 from mountain B.
Draw the line 135 on the map which start from the
mountain A, and draw another line 270 on the map
which start from the mountain B.
Your current position on the map will be at the
intersection point (point A) of the lines 135 and
270
Please check if the trek course is correct.
The XG-30 can keep your course correct during
trekking. Let's use the sample trail A-E on the
adjacent diagram to illustrate this application.
Mark the points where the trail turns its direction or
the trail branches its way, such as the point A, B, C,
D and E on the adjacent diagram.
Check out the bearing directions of point B from
point A (315 ), point C from point B (0 ), point D
from point C (225 ), and then point E from point D
(315 ).
Make sure that the heading direction is 315 in the
section A to B. Performing the similar checking
when trekking in the other trail sections.
IMPORTANT:
If you are in doubt of the directions and
positions of the trail, consult the park administration
office before starting the trek.
+
+
8
8
+
8
8
+
8
8
+
+
+
8
8
8
8
+
8
Magnetic Declination Compensation
+
To compensate an object's magnetic bearing
to true bearing(TB): Subtract westerly (W)
magnetic declination or add easterly (E)
m a g n e t i c d e c l i n a t i o n w i t h t h e m a g n e t i c
bearing (MB).
+
8
magnetic bearing
8
+
8
8
+
8
8
+
8
+
8
+
8
magnetic bearing
8
+
8
8
+
8
8
+
8
+
8
Example 1
: Westerly magnetic declination 23
and the
323 .
TB = MB - W. While MB = 323 ; W =23
TB = 323 - 23
TB = 300
The true bearing will be 300 .
Example 2
: Easterly magnetic declination 22
and the
278 .
TB = MB + E. While MB = 278 ; E = 22
TB = 278 + 22
TB = 300
The true bearing will be 300 .
True North
Magnetic
Declination
Magnetic
Declination
Magnetic
North
4110 m
2120 m
3120 m
point A
(starting point)
point B
A Sample Trail on a Map
point D
point E
(finish point)
point C
315
8
225
8
0
8
315
8
mountain B
Check Current Position By Backward Bearing
mountain A
270
8
135
8
point A
0
0
Compensate th e Bearin g
with Weste rly (W ) Magnetic Declin atio n
Compensate th e Bearin g
with Easte rly (E ) Magnetic Declin atio n
Tru e Bearin g (T B) =
Magneti c Bearin g (M B) - Weste rly Magneti c Decli nati on (W )
Tru e Bearin g (T B) =
Magneti c Bearin g (M B) + Easte rly Magneti c Decli nati on (E )
300
8
(T B) = 278
8
(M B) + 22
8
(E )
300
=
(M B) - 23 (W )
8
(T B)
323
8
8
magnetic
declination
23
8
W
magnetic
declination
22
8
E
true
bearing
300
8
true
bearing
300
8
magnetic
bearing
323
8
magnetic
bearing
278
8
true north
0
8
true north
0
8
magnetic
north
magnetic
north
object B
object B
point A
point A
9.7 Compass Mode -
Magnetic Declination of Major Cities
No. Country/Place Major City Declination
33 Netherlands
Amsterdam
1-W
34 New Zealand
Wellington
22-E
35 Norway
Oslo
0
36 Pakistan
Islamabad
2-E
37 Philippines
Manila
1-W
38 Portugal
Lisbon
5-W
39 Russia
Moscow
9-E
40 Singapore
Singapore
0
41 South Africa
Cape Town
23-W
42 Spain
Madrid
3-W
43 Sweden
Stockholm
3-E
44 Switzerland
Bern
0
45 Taiwan
Tai-pei
3-W
46 Thailand
Bangkok
0
47 UAE
Abu Dhabi
1-E
48 United Kingdom
London
3-W
49 United States
Washington, DC
10-W
50
Juneau
25-E
51
Phoenix
12-E
52
Little Rock
2-E
53
Sacramento
16-E
54
Denver
10-E
55
Atlanta
4-W
56
Honolulu
10-E
57
Boston
16-W
58
Saint Paul
2-E
59
Jackson
1-E
60
Santa Fe
10-E
61
Oklahoma City
6-E
62
Salem
18-E
63
Harrisburg
11-W
64
Salt Lake City
14-E
No. Country/Place
Major City Declination
1
Afghanistan
Kabul
2-E
2
Australia
Canberra
12-E
3
Austria
Vienna
2-E
4
Bahrain
Manama
2-E
5
Bangladesh
Dhaka
0
6
Belgium
Brussels
1-W
7
Brazil
Brasilia
19-W
8
Canada
Ottawa
14-W
9
Chile
Santiago
5-E
10
Beijing
6-W
11 China
Hong Kong
2-W
12 Costa Rica
San Jose
0
13 Cuba
Havana
3-W
14 Czech Republic
Prague
2-E
15 Denmark
Copenhagen
1-E
16 Egypt
Cairo
3-E
17 Finland
Helsinki
6-E
18 France
Paris
1-W
19 Germany
Berlin
1-E
20 Greece
Athens
3-E
21 Hungary
Budapest
4-E
22 India
New Delhi
1-E
23 Indonesia
Jakarta
1-E
24 Israel
3-E
25 Italy
Rome
1-E
26 Japan
Tokyo
7-W
27 Jordan
Amman
3-E
28 Kenya
Nairobi
1-E
29 Korea
Seoul
7-W
30 Malaysia
Kuala Lumpur
1-E
31 Mexico
Mexico City
6-E
32 Nepal
Kathmandu
0
China
Jerusalem
