Map, Compass & GPS

Map, Compass & GPS
Wild flowers along Fall Creek on the way to the Green Lakes - Oregon

Sunday, January 15, 2017



What do you do when a compass breaks or the GPS just doesn’t seem to be working right?  Here are a few suggestions that will help the navigator.

The theme of this post is to discuss what options the backcountry navigator has with equipment that might not be working correctly. 

When equipment does not appear to provide the correct indication (such as the GPS bearing to the trail head) it’s time to stop.  Never rush navigation.  Stop and take the time to really look over the information provided.  Consult with the rest of the group.

Being able to recognize the proper operation of the hiker’s equipment is important.  This is obtained through field checks well before any trip.  The gas stove can be tested at home before the journey.  The navigation kit can be evaluated throughout the year at the local park or forest. I recommend to the elk and deer hunters in my GPS classes to take their receiver everywhere they go for two weeks prior to leaving for camp.  Push buttons, change displays, mark a waypoint and finally, return to a destination.  Like a pilot of a plane, a map, compass and GPS are the instruments in the backcountry cockpit.

Normally a magnetic compass’ needle rotates freely.  The needle rotates on a jeweled pivot point.  The magnetic compass should be kept level while in use allowing the magnetic needle to move about in the compasses housing.  My Suunto recently just stopped rotating.  I would change direction about 30 degrees and the magnetic needle would move about 15 degrees and then just hang up.

Sadly, there is no simple in the field fix for this.  I gently tapped the compass body and checked the movement of the housing but nothing seemed to work.  Never let broken gear clutter your pack or be used mistakenly.

A back up compass is very helpful in such a situation.  It doesn’t have to be expensive, just reliable.  No matter what you use for a back up, it has to work well and requires testing.  I take all my new compasses to a location in town where the streets run north and south (degrees true.)  I will hike the streets insuring that the compass is on the mark.  This only takes a few minutes.  Recently I noticed that one of my small ball compasses seemed to be at least 20 degrees off; it’s a goner.  Note, that a small back up compass may not be as precise as your primary model.  Also recognize that some compass will only provide a trend of direction such as moving in a northerly direction as opposed to tracking on a direction of 025°.

Before throwing a quality compass out, contact the manufacturer to see what the warrantee offers.

So what does the hiker do if the GPS receiver appears to be broken?   .
The following are steps that I’ll perform:

1.    If I have a GPS with an electronic compass I’ll ensure the compass is activated.  For example on the Garmin 60 series, pressing and holding the “page” button will turn the compass on or off.

2.    I’ll ensure the electronic compass is calibrated.  The compass must be calibrated after each battery change.

3.    Check the charge on the batteries.  If in doubt replace them.

4.    When the “Go To, Find or Where Is” option has been selected, older models will require motion to cause the compass arrow and displays to adjust.  Take five or more steps and see if there are any changes with the display.

5.    Turn the GPS receiver off, open the battery case and remove one battery for about twenty seconds, return the battery and power up the receiver again. 

6.    Once powered up, I want to be certain that the receiver has captured the signals from at least four satellites.

7.    Worse case - call the manufacturer.  Call early in the morning.

In the field, I leave my receiver powered on, collecting data the entire trip.  I keep my receiver in a holster that attaches to one of my shoulder straps.  Before leaving the trail head I “dump the junk” and get rid of old waypoints (e.g., last year’s fishing trip hot spots), I reset data fields on the odometer page and I will clear out my track log.  As I hike, my receiver is collecting all my trail data.  Should my receiver’s compass display fail I can follow my track (the “bread crumb trail” on the map page) back to the trail head.

Lastly, I will consult my map. Using the major land features (e.g., ridge lines, peaks, etc.) I will orient the map, determine my location (using terrain association) and direction of travel.
In late November 2013 my local newspaper, the Bend Bulletin (Bend, Oregon) published a supplementary insert called the High Desert Pulse.  On page 28 there was a superb article by Elise Gross titled “Cover Your Bases.”

A base layer is the garment worn closest to the skin.  In the past, most outdoorsmen thought of a base layer as a simple set of “long johns.”  The days of cotton long johns are fading.  Cotton clothing retains moisture and in winter provides no insulation when wet. 

 Ms. Gross provided a fine discussion of the options of the various base layer choices available to the hiker.

She states:

“.. Your activity level and the temperature should be taken into account when choosing a base layer.”

“Fabric type should also be considered.  Base layers are made of a variety of fabrics with unique properties.”

The following is a brief synopsis of what is available.

·         Wool - Merino wool is at the top of my list.  Merino is soft and doesn’t irritate the skin.  Smart Wool is my favorite.  Wool works well in mild to cold temps.  Wool wicks sweat away from the skin.  It dries relatively quickly.  Wool is antibacterial so it doesn’t start to smell over time as silk and poly does.  It’s expensive.

·         Silk – Silk that has been modified to improve wicking is a fine choice (untreated silk absorbs and retains moisture).  Silk works well during periods of heavy physical exertion.  Though it can get too warm, silk works well in cold climates.  Silk takes longer to dry than wool or polyester.  Silk can get stinky so launder after use.


·         Synthetics – These are popular big sellers and big advertisers in outdoor magazines (e.g., Under Amour).  Synthetics are fine in moderate temperatures.  Wet material close to the skin may be chilly until dry.  Moisture wicking is excellent; that’s the big plus.  Synthetics dry faster than any other base layer material.  Synthetics can get stinky so launder after each use.  

All products mentioned are light and take up little space.
Consider carrying an extra top to keep the hiker dry and warm. 

Monday, January 2, 2017

Buying a GPS After The Holidays


The post Holiday Season is a great time to start looking for a new GPS.  There will be sales over the next few weeks.  Manufactures are offering discounts and coupons can be found on line.  Search the Internet for sales promotions and the ads in the Sunday paper.  I will occasionally use www.walmart.com to establish a price baseline.  Take a look at www.gpscity.com too.

Be careful when using “Craig's List.”

Some models with good discounts could very well be out of production units and discontinued.  Evaluate what your needs are and if the price is right and the receiver fits all your requirements, then you are set.

One web site to take a look at is www.GPStracklog.com.  GPStracklog.com is packed with information on what’s new and happening in the world of GPS.  Importantly, at the top of the page, click on “buyers guide” and then select the category that fits your requirements (e.g., auto, outdoors, etc.)

I think the recommendations provided are spot on the mark.

What would I avoid? I am very cautious when buying used GPS or one that has been refurbished.

I want a model that allows me to:

·         Enter many waypoints
·         Edit waypoints
·         Manually enter waypoints (example: your friend provides you the coordinates to a wonderful place next to a bubbling broke for a camping site)
·         Many map datum selection options
·         Will accept topographic maps.
·         Those with less steady hands might consider are receiver with buttons on the front.  Test this in the store or borrow a friend’s.  Ditto for touch screen models.
·         Up load and download GPS waypoints and track data.


Good luck in your search for that new GPS!!

Monday, December 26, 2016

Sighting With a Magnetic Compass

Sighting with a compass is an important skill that can determine direction to an object or help the hiker locate and identify his position in the backcountry.

A compass is an important part of the backcountry navigator’s kit.  The use of Global
Positioning System (GPS) receivers has simplified navigation to an extent but the knowledge of how to use a compass is still important; do not underestimate this skill.  

“A compass is basically a magnet mounted on a pivot, free to turn in response to the pull of the earth’s magnetic field.  The housing protects the needle and helps you relate the direction in which the needle points to directions on the map and on the land.  A compass by itself can’t tell you where you are or what you are looking at but it can tell you about direction….”
Staying Found, The Complete Map & Compass Handbook, by June Fleming

Sighting with a compass allows the hiker to determine the direction to an object such as a mountain peak.  The compass direction to an object is known as the “bearing” or azimuth.   Bearing is the more common term in outdoor recreation and is a term used heavily in GPS navigation.  For example, if a mountain peak is due north of you, the bearing to the peak is 000° (read as zero zero zero degrees.)

Sighting with a compass allows the hiker to do several things.  First, sighting on a distant object can provide direction to that object and repeated sightings can provide course corrections along the way.  Secondly, with several sightings on different objects a person’s position can be triangulated. 

This article will focus on using a standard baseplate compass such as the two examples pictured below.  (The lensatic and military compass will not be discussed.)


Figure 1 Two examples of good baseplate compasses.

Key features of the two compasses (above) include:

  • They are declination adjustable
  • Liquid filled housing to dampen the magnetic needle’s movement
  • 2° increments on the bearing dial of the compass housing
  • A clear baseplate of adequate size with map scale information and a small magnifier.
The picture below offers a quick review of the components of a baseplate compass.






To sight or take a bearing do the following:

  1. Using the owner’s manual, adjust the compass for declination.
  2. While holding the compass at waist level, turn squarely towards a distant object.  Hold the compass so that the direction of travel arrow points directly at the object. (Point the      direction of travel arrow away from you; perpendicular to your body.)









  1. While holding the compass, turn the compass housing (the dial) and align the orienting arrow (engraved in the rotating housing) underneath the red magnetic needle.













  1. In this example, the compass has been adjusted to a bearing of 011° degrees.  The bearing data is found where the direction of travel arrow intersects the compass housing.
At this point the hiker can walk towards the object (e.g., mountain peak, or abuilding) on a bearing of 011°.

If the hiker needs to determine his position, the next step is to triangulate using three bearings.  In a “nut shell” this means that bearings to three clearly identifiable features are used.  Ideally, objects that have a bearing separation of 30° – 60° will be used.  Good bearing separation provides better fixing information and plots on the map cleanly.  The bearings are then plotted on a map and where the three lines cross is the hiker’s location.  This complete process is called triangulation.

The following are suggestions for triangulating a position in the back country.
  1. Identify three distinct objects to sight on.  Note that the objects need to be on the topographic map (topo) of the area.  I recommend carrying a forest service map (or something similar) of the area in addition to the topo just incase the objects are too far away.
  2. Orient the topo using the compass.  Orienting the topo means that the map’s left or right border is pointing to true north or 000° degrees true.  See “Orienting a Map” for more information.
  3. Sight on an object such as a mountain peak or church spire.  (Note that not many objects in the backcountry are so distinct and crisp.  Do the best with what you have.) Ensure the direction of travel arrow is pointed towards the object.
  4. As discussed earlier, turn the compass housing until the orienting arrow is directly under red magnetic needle.  Do not move or rotate the compass housing, keep the new bearing in place.
  5. At this point, and while plotting the bearing on the map, the compass will now be used like a protractor.
  6. Lay the compass on the map with either the top left or right corner of the baseplate on the landmark.  This will be a pivot point while aligning the compass.
  7. With the edge of the baseplate in position, rotate the compass (swing) left or right until the N (north) of the compass housing aligns with map North (the top of the map.)  What is even better, with the map oriented to north, as the baseplate is rotated, the red magnetic needle will swing back into position on top of the orienting arrow. 
  8. Draw a line (along the baseplate) from the object to your approximate area.
  1. Repeat the process two more times.


  1. Ideally the three lines will intersect in the immediate area but because of compass error and human error the point of intersection maybe spread out.  Still, triangulation will put you in the ballpark.  Use terrain association to help narrow down your position.

Monday, December 19, 2016

Hiking In The Rain

Philip at SectionHiker has a great post about hiking n the rain.  This isn't about a gentle hike through the glenn, this is about key elements when hiking in heavy weather; mud is not optional.

Friday, December 9, 2016

Topographic Map Symbols


Colors and symbols add the detail unique to a topographic map.  These details may not be found in gazetteers or travel guides.  Map detail includes important information about elevation, water, structures, trails, ground cover and roads; and much more.

 “The mapmaker has been forced to use symbols to represent the natural and man-made features of the earth’s surface.  These symbols resemble, as closely as possible, the actual features themselves as viewed from above.”

                                                                        U.S. Army Field Manual FM 21-28                                                                                                     Map Reading and Land Navigation, 1993

Topographic maps are rich in symbols.  Specific to a location, symbols identify features such as buildings, springs, bench marks, mines and bridges.  The United States Geologic Survey’s (USGS) guide Topographic Map Symbols is four pages long and lists dozens of symbols.  To view the USGS’s complete listing go here.

The following graphics are a sampling from Topographic Map Symbols.  The symbols below are those used for rivers, lakes and canals.  Note the different colors used.
The graphic below illustrates symbols related to buildings and other man-made features.



Note that the color of these symbols is predominantly black.


Let’s highlight a few symbols that the backcountry hiker will find helpful (the symbol will be listed to the left.)

 Bench Marks are survey monuments.  Location and elevation data is accurate.   Bench Mark will be represented by the letters BM and next to it will be printed the elevation data; see map above.  In the backcountry, Bench Marks will have a brass/bronze plate at the location to identify the mark and its position data.  Please do not tamper with a Bench Mark.


A trail is highlighted in the map above.  Trails are black dashed lines.


     Useful to the hiker are four wheel drive roads (4WD) and unimproved roads.  These are commonly called jeep roads and may be usable on foot, horseback or mountain bike.  Some of these roads may not be passable by vehicle.           

Thin, powder-blue lines represent streams.  What looks like a dashed blue line (right half) represents an intermittent stream; a flow that may disappear in dry weather.


I recommend spending some time browsing through Topographic Map Symbols and to become familiar with the symbols listed. The web site www.landnavigation.org provides a fine review of colors and symbols that are linked to photographs.s

Thursday, December 1, 2016

Navigation Web Site

I came across the web site www.mapnavigation.net.

This is a comprehensive site covering land navigation and is based on the US Army's land navigation field manual.

It's worth the time to give this one a scan.