NEXUS
COMPASS
GUIDE
A Practical
Field Guide
for Map &
Compass
Use
Congratulations on purchasing a Nexus map compass, an easy to use, reliable
navigation tool. Nexus recommends you read and understand the basic
navigational skills outlined in this instruction pamphlet before going afield.
Remember, prepare before you go. Tell others where you are going. Carry a
map and compass, a complete survival kit and know how to use them.
CAUTION: Your compass will only locate Magnetic North and bearings
(directions) from your present location. You have to remember the direction
you have been traveling, the direction back to your starting point and keep
track of your present position on the map. IF YOU BECOME LOST, Admit it,
and try to remember where the map and the terrain matched. Backtrack
to that position with your compass. IF YOU STILL ARE LOST, Stay Put
and do not wander or panic. Shelter yourself from the elements. Wait for help
and be prepared to signal your position to rescuers.
Travel Arrow
Flèche directionnelle
Vial
Fiole
Azimuth Ring
Cadran Azimutal
Map Scales
Échelles de la carte
Magnetized Needle: Red/White hot-stamped Swedish steel needle with a friction free jeweled bearing.
Permanently magnetized and suspended on a polished stainless steel pivot.
Graduated Dial: Rotating dial marked in 2 degree increments from 0-360° degrees. Cardinal points at North
“N” = 0°, South “S” = 180°, East “E” = 90° and West “W” = 270° are clearly indicated.
Orienting Arrow/Lines & Red N: Red/Black arrow and lines imprinted on clear vial bottom and Red N on the
dial match with the needle for positive directions.
Declination Correction scale: Printed at the head of the Orienting Arrow, 0-60 degrees marked every two
degrees, for East and West declination.
Capsule: Filled with a clear non-yellowing, anti-static liquid that dampens the movement of the Magnetized
Needle in four seconds or less.
Map Scales: Imprinted scales, e.g., inch, mm, mile, kilometer, on the base plate used to measure distance on
maps. Refer to maps margins for scale information. (i.e. USGS 7.5 min., 1:24,000 scale)
Travel Arrow: Base plate arrow used to point or sight the compass to your destination or direction of travel.
Sighting Systems: Directional, Mirrored and Optical.
Sighting Systems: Directional, Mirrored and Optical.
(Figure 2A)
(Figure 2B)
Directional Sighting: Object or
direction is sighted using the
“Travel Arrow.”
Visée directionnelle : L’objet ou la
direction est relevé à l’aide du pointeur.
Models 3, 7, 8 (Figure 2A)
Mirrored Sighting: Object or direction is sighted over mirror
through “V” notch while needle alignment and azimuth ring
are read in reflection of mirror.
Visée à miroir : L’objet ou la direction est relevé au-dessus du miroir
par le biais de la mire (rainure en “V”) au moment où l’alignement de
l’aiguille et le cadran azimutal sont prélevés en réflexion du miroir.
Models 15, 16, 25, 26, 27 (Figure 2B)
Figure 15B
Figure 3A
Figure 4
Figure 12
Figure 15
Vertical Height Formula
Figure 14B
Figure 3D
1. How A Compass Works
Your compass is a navigational instrument that provides directions or bearings, using the Magnetic North Pole
as a reference. Its graduated dial lets you set a bearing to your intended destination. Following your BEARING
and measuring the distance traveled (counting stride, time or plotting locations on a map) is all that is required
for successful navigation.
2. Getting to know your Compass (Figure 1)
Declination Scale
Échelle de déclinaison
Orienting Arrow
Pointeur
Travel Arrow
Flèche directionnelle
Read Bearing Here
Lisez le relèvement à
ce moment
Figure 3B
Read Bearing Here
Lisez le relèvement à
ce moment
3. Sighting & Following a Compass Bearing
Hold your compass level in front of you, with the Base
Plate Travel Arrow pointing towards the direction you
wish to go. Do not point the compass with your hand.
Turn your whole body. When your compass is held flat,
the Magnetized Needle will rotate freely and its RED
end will point towards Magnetic North. (Figure 3A)
Holding the compass level, rotate the Graduated
Dial until the Orienting Arrow and Red “N” are
aligned with the RED end of the Magnetic
Needle. (Figure 3B)
Your Bearing or Direction of Travel can now be read in Degrees at the
Index Line on the dial at the base of the Travel Arrow, which now points
precisely to your destination. (Figure 3C)
Look up, sight a landmark (rock, tree, etc.) along the bearing path, using
the Travel Arrow as a guide. Take care not to mis-align the Magnetic
Needle. Keep it centered inside the Orienting Arrow. Now walk towards
the landmark. Repeat this procedure until you reach your destination.
(Figure 3D)
When you repeat this process, identify landmarks along your bearing path
(the further away the better) and walk to them. You can navigate around
difficult terrain such as streams and cliffs, while still maintaining your
original bearing.
If you are using a Nexus compass that has a Sighting Mirror, adjust the
mirror so that it reflects the entire compass dial as you look across the
Base Plate. Hold the mirror “V” Notch on the object sighted and keep the
Sighting Line in the mirror, running through the center of the compass
needle and aligned with the Index marks. Turn the Graduated Dial until the
Orienting Arrow is aligned with the Magnetic Needle. Your Bearing will be
read at the Index line next to the mirror hinge. Follow your Bearing as
indicated above.
4. Using a Topographical Map
Topographical maps present a 3 dimensional picture of the land viewed
from above. Features are designated by color and symbol: Cultural
features or
man-made (Black), water (Blue), vegetation (Green), and
elevation (Brown). Elevation is indicated by contour lines, on which every
point along the line is at the same height above sea level. The closer the
contour lines, the steeper the slope. Every fifth line is darker and has a
number representing the height above sea level. Contour lines also show
the shape and form of the land. Maps are made to a scale, which
represents a proportion to the distance between points on the map and the
actual distance between the same points on the ground.
Large scale maps, such as a 1:24,000 U.S.G.S., on
which features appear big, show the most information
for hiking and camping. The legend at the base of the
map indicates the scale, contour interval and special
symbols shown. (Figure 4)
5. Understanding Declination
Declination (or variation) is the difference between True
North (to which maps are drawn) and Magnetic North
(as indicated by a compass). You Must adjust for
declination, East or West, when using a compass with a
map. Declination varies throughout the world and is
shown on topographical maps with a diagram,
identifying Magnetic North (MN) and the degree variance from True North
(TN). Magnetic fields fluctuate slowly at varying rates around the world. It
is best to use an up to date map for current declination. Visit our web sight
or call Brunton for an accurate declination variance in a specific location.
(Figure 5)
True North
Nord géographique
13°
230 mils
Magnetic North
Nord magnétique
Optical Sighting: Object or direction is sighted through
prism while bearing is read direct from scale.
Visée optique : L’objet ou la direction est relevé à travers le
prisme. À ce même moment, vous pouvez noter le relèvement
directement de l’échelle de déclinaison.
Models 54 and 80 (Figure 2C)
(Figure 2C)
Topographical Map Manufacturer
U.S.G.S. Maps: (800) 872-6277
Trails Illustrated: (800) 962-1643
DeLorme Mapping (207) 865 4171
Figure 9
Figure 10A
Figure 11B
Figure 11A
Figure 10B
Magnetized Needle
Aiguille aimantée
6. The Nexus 1-2-3 Method (Paralleling System) automatically corrects for
Declination.
The Nexus 1-2-3 Method can be used with all Nexus compasses
on maps which have Magnetic Meridians drawn to the map’s declination. Find
your local declination at the declination diagram on the base of the map.
(Figure 6A)
1. Align the side edge of the Base Plate with your present location and
destination on the map. (Figure 6B)
2. Turn the Dial so the Orienting Arrow and Lines are aligned with the
Magnetic Meridians on the map. Make sure the Red “N” is pointed to
North on the map. The magnetic bearing to your destination can be read
at the Index Line on the Dial. (Figure 6C)
3. Holding the compass level in front of you, turn your body (not the
compass), until the Red End of the Magnetic Needle is aligned with the
Orienting Arrow and pointing to the Red “N” on the Dial. The Travel
Arrow now points precisely to your destination. Look up, sight on a landmark
and walk to it. Repeat this procedure until you reach your destination.
7. Nexus Declination Correction Scale when the paralleling system is
not used. Another system most Nexus compasses have is a Declination
Correction Scale inside the vial, on which the Magnetic Needle can register,
when the Paralleling System is not used.
As in the Nexus 1-2-3 Method:
1. Align the edge of the compass with your present location and destination on
the map.
2. Turn the Dial so that the Orienting Lines are aligned with the side margins
of the map or with True Meridians drawn on the map to get a Bearing to
your destination. The compass dial’s Red “N” must point to North on the map.
(Figure 7A)
3. Hold compass level. Turn body until the Red tip of the Magnetic Needle
registers on the Correction scale of the declination for the map sheet. You will
be facing the Magnetic Bearing needed to get you to your destination.
(Figure 7B)
Note: the Bearing read at the Index line on the Graduated Dial will be a True
or Map bearing.
8. Map Bearings with “North” oriented map.
Orienting Map to North
a.) Using the Declination Correction scale, rotate the
Graduated Dial with North (0°) at the Index Line.
b.) Place edge of compass on the map margin with the Travel
Arrow pointing towards the North end of the map. (Figure 8A)
c.) Without moving the compass, rotate the map until the
Magnetic Needle points to the correct declination on the
Correction Scale. The map is oriented. (Figure 8B)
9. Map bearings with “North” oriented map.
Orienting Map to North
a.) When using the Paralleling System with Magnetic Meridians drawn on
the map, place edge of compass on the map margin with the Travel Arrow
pointing towards the North end of the map.
b.) Rotate the Graduated Dial until the Orienting Arrow or Lines are aligned
with a Magnetic Meridian line.
c.) Without moving the compass, rotate the map until the Magnetic Needle
points aligns with the Orienting Arrow. The map is oriented.
By aligning your map to North, the terrain around you can easily be identified.
Features on your map will match their location in the field. Place rocks on the
map corners to keep the map oriented. Aligning the map to Magnetic North
lets you use the map to sight bearings FROM and TO your map. (Figure 9)
10. Establish a Map Bearing
a.) Orient map to North.
b.) Place the edge of compass on the map along the desired Line of
Travel to your destination. Make sure the Travel Arrow is pointing
towards destination. (Figure 10A)
c.) Hold compass Base Plate on map and rotate the Graduated Ring
until the Magnetized Needle is aligned with the Orienting Arrow.
(Figure 10B)
d.) Read your True Bearing at the Index Line. Note: When using
the Paralleling System, your Bearing will read Magnetic.
11. Field Bearing to Map
a.) Orient map to North.
b.) Identify a landmark on the map, which can be
sighted from your position.
c.) Sight compass to the landmark with the Travel Arrow. (Figure 11A)
d.) Rotate the Graduated Dial until the Orienting Arrow is aligned with the
Magnetic Needle. Your Magnetic Bearing is read at the Index Line.
e.) Place edge of compass against the map’s landmark with the Travel Arrow
pointing toward it. (Figure 11B)
f.) Keeping compass edge on the landmark, pivot the
compass until the
magnetized needle is aligned with the Orienting Arrow. Plot bearing on map
by drawing a line from the landmark to your location, using the edge of the
compass. (Figure 11C)
Figure 5
Figure 3C
Figure 6A
12. Resection is used to locate your present position with the Field Bearing to Map
method. By plotting (drawing) bearings from two or three identifiable landmarks (at
least 45 degrees apart), in the field to your map, the lines will intersect at your present
location. When three plots are used, a triangle will from and your location is found
inside the plotted triangle. (Figure 12) You can also use a single Bearing, if sighting
from a linear feature, e.g., road or stream shown on the map.
13. Intersection is a way of using the Field Bearing to Map method to plot the location
on your map of a feature not indicated. From at least two identified positions on the
map, field bearings are sighted to the feature to be plotted and drawn on the map.
Where the lines intersect, the feature is located.
14. Using your Inclinometer
(Red pendulum indicator found in the Elite and Pro-Elite models)
a.) Open the compass cover completely and rotate the Graduated Dial
until West ( 270°), is at the Index Line. (Figure 14A)
b.) Hold compass at eye level on its side until the Red Clinometer Needle
moves freely. Read clinometer needle against the declination scale at the
base of the capsule. Let one long side of the compass coincide with the
slope of the terrain to measure the angle.
c.) Read inclination in degrees at the scale. (Figure 14B)
d.) The Inclinometer can also be used with the mirror for height
measurement. Hold compass on its side so that you can read the
reflected inclinometer scale in the mirror. Sight along the base plate edge
to the top of the object being measured. Read the angle in degrees at the
clinometer needle against the reflected scale.
15. Vertical Height Formula
Degree to Percent (%)
Move Tangent decimal 2 places to the right.
Example: Angle = 20°
tan (20°) = .364 = 36.4%
Degré exprimé en pourcentage (%)
Déplacez la décimale de la tangent deux positions vers la droite.
Exemple : Angle = 20°
Tangente (20°) = ,364 = 36,4%
Height Formula
Height = tan (angle) x Distance.
Example: 20° Distance = 66’
Height =
tan (20°) x 66’
=
.364 x 66’
Height =
24.024 = 24’
Formule de hauteur
Hauteur = Tangente (angle) x distance
Exemple : 20° - distance 66 pi
Hauteur = Tangente (20°) x 66 pi
= ,364 x 66 pi
Hauteur = 24,024 (24 pi)
Figure 6B
Figure 6C
Figure 7A
Figure 7B
Figure 8A
Figure 8B
Figure 14A
Figure 16B
Height On Level Ground - Figure 15 (Left)
Height =
(tanA + tanB) x distance
=
(tan30° + tan14°) x 66’
=
(.577 x .249) x 66’
Height =
(.826) x 66’ = 54.516 = 54.5’
Hauteur au niveau du sol – Figure 15 à gauche
Hauteur = (tangente A + tangente B) x distance
= (tangente 30° + tangente 14°) x 66 pi
= (,577 x ,248) x 66 pi
Hauteur = (,826) x 66 pi = 54,516 = 54,5 pi
Height On Sloping Ground - Figure 15 (Right)
Height =
(tanA - tanB) x distance
=
(tan42° - tan4°) x 66’
=
(.900 x .070) x 66’
Height =
(.830) x 66’ = 54.780 = 54.8’
Hauteur en sol incliné – Figure 15 à droite
Hauteur = (tangente A - tangente B) x distance
= (tangente 42° - tangente 4°) x 66 pi
= (,900 x ,070) x 66 pi
Hauteur = (,830) x 66 pi = 54,780 = 54,8 pi
A=20°
Figure 11C
Figure 16A
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Read Time Here
Lisez le relèvement
à ce moment
16. Special Compass Features
The Nexus Model 27 Trooper compass contains a Sun Watch as an additional
feature. The watch is used by:
a.) Using the Sighting Mirror with the compass held level, take a bearing in the
direction of the sun. (Figure 16A)
b.) Rotate the Graduated Dial to align the Orienting Arrow with the Magnetic Needle.
c.) Turn the Base Plate over to see the Hour Scale. The Orienting Arrow points to the
approximate time of day (Standard Time). (Figure 16B)
17. Nexus Compass Care.
Nexus compasses are very accurate and are built to withstand tough field conditions.
Here are some things you can do to get the best results from these fine instruments.
• Always keep the compass level so the magnetic needle moves freely.
• Needle accuracy can be affected by steel, iron and electrical devices that are close to the compass. Avoid
them. Prolonged exposure could reverse the needle polarity.
• High temperatures above 140°F, can expand the compass capsule and cause it to leak. Protect your
compass from direct exposure to the sun or to heating elements.
• Low temperatures and atmospheric pressure can cause small bubbles to appear in the capsule liquid. They do not affect compass
accuracy and will disappear upon return to normal conditions. The appearance of a bubble over ¼” in diameter indicates the capsule is
damaged and will have to be replaced.
• Nexus compasses have luminous points which are non-radioactive. They need a light source or sunlight to activate. They will shine for
about 20 minutes and then need to be re-exposed to light.
• Petroleum products and insect repellents with DEET® will cloud the compass surface and remove markings. A clean compass will give
many years of trouble free use.
18. Southern Hemisphere Use
If you are traveling to the southern hemisphere your compass should be balanced for the earth’s southern
magnetic inclination. Contact the Brunton Co. for compass balancing information.
