Buying A GPS Receiver

Looking for a GPS?  Here are a few suggestions.

Buying your GPS receiver is a lot like shopping for your a car. You want reliability and simplicity in providing transportation from Point A to Point B. There are many outdoor opportunities that may impact what kind of GPS model suits your specific needs. As a hunter or hiker you need to shop intelligently. Here is what you need to know:

         Start with a quick education of common GPS terms, and why they’re important.

• Waypoints – These are your navigation coordinates that you have saved to memory within the GPS. Most receivers will hold 500. That said, you only need to keep a few on your GPS all the time. Use the free program at www.easygps.com to store the rest.
• Find/Go To – This is the navigation function of the receiver. It is this function that will “steer” you to your destination.
• Coordinates: This refers to a geographic grid system and pinpoints your position in the world. The most common is Latitude and Longitude though many outdoorsmen quickly shift to Universal Transverse Mercator (UTM) because of its simplicity.
• Compass – An electronic counter-part to your magnetic compass. The GPS compass is dependent on batteries, like the rest of the system, so don't leave your magnetic compass at home.

Every GPS has these basic features. Anything additional are bells and whistles. It will be up to you to determine which ones are functionally important. For example, I am both a hunter and backpacker. I like a GPS with a Barometric altimeter because I use that function to monitor atmospheric pressure at high elevations. I know through personal experiences that when the pressure drops the weather is changing - I may be looking for shelter.

When looking to buy a GPS receiver consider the following:

• Decide how much you want to spend. If you don’t know what a GPS might cost, visit www.walmart.com, www.gpscity.com and www.rei.com to get a good price baseline. Check the manufacturer’s web site (such as www.garmin.com) for rebate offers. Then research the web with for reviews on specific models.
• Ask friends with GPS’s what they use theirs for and what their recommendation would be. One size definitely doesn’t fit all! An avid geocacher would have different needs than a hunter. A hunter might opt for a model with a two way radio such as the Garmin Rino series.
• Older folks and those not “tech savvy” seem to do better with a GPS that has buttons on the front (GarminMap 62/64 series); it seems to be more intuitive. As an instructor, I've found that buttons along the side can become frustrating for people with less steady hands.

In the store, pick up the receiver, look at the controls and hold it as you would when using it.  Ask yourself: 

• Does it feel like a good fit?

• Can I read the buttons and comfortably push them? (With gloves?)

• Is the screen size adequate? 

• Is the GPS simple or just too complex for me?

• Mapping programs are nice but expect to pay $100.00 or more.  Ask a friend with a GPS and see for yourself if the mapping is an asset for you.  Can you read what is presented on the screen or is it just clutter?  Visit GPS File Depot for free maps to load on your GPS.

• Find out what the store’s return policy is on electronics and what their return rate is with various models. 

• Whatever you buy, hang on to that receipt and register the product soon after purchase. 

 Once you buy a GPS:

• Keep fresh batteries in it.  Don’t put it in the closet, or store it in your survival kit. Take it out and use it; now.  You can’t break it,.
•  You should practice your GPS and map and compass skills often.  Your  wilderness land navigation skills could, given a bad turn of weather or situation, become  a matter of survival. 
•  Visit the manufacturers website once every six months or so.  The manufactures frequently offer free up-grades allowing the GPS’s internal software to run more efficiently.  It is usually a simple down load to make your GPS current.

A good way to learn is to take a class where you will learn the basics and how your receiver works.  Check with your local Community College’s continuing education program or Sporting Goods stores to see if they offer classes.

And don’t forget: a GPS is no substitute for a map and a quality compass and the knowledge of how to use them.  The most expensive GPS on the market is only as good as its batteries.  Anything electronic can fail and they do so at the most inconvenient time.

Topographic Maps

Philip Werner at Section Hiker has a super post about the poor quality of the new USGS topograhic maps.


"Have you ever noticed how incomplete and out of date digital maps are when it comes to hiking trails? At least on the free USGS maps you can download on the web and that come bundled with GPS devices or Smartphone navigation apps. In my neck of the woods, you still need to use the waterproof paper maps published by local cartographers because they’re far more up-to-date than digital maps."

Check Philip's full post.

Pace - Measuring Distance in the Backcountry

 Many outdoorsmen measure distance in the backcountry by using a Global Positioning System (GPS) receiver.   GPS receivers are reasonably accurate, real time, and provide distance traveled and distance to a destination.

But what does the hiker do if they don’t have a receiver, the GPS fails or batteries die?

A proven method for estimating distance is known as pacing.  Pacing is not as accurate as the GPS receiver, but it can give a reasonable approximation of the distance traveled.  Together with a map and compass, pacing is an important component of evaluating a hiker’s track through the backcountry.  In darkness or periods of low visibility pacing helps to determine the hiker’s location through a process known as dead reckoning. 

Pacing is a method that begins with measuring one’s stride, with the intent of determining an individual’s length of stride. A pace is a measured two steps; a complete stride.  As illustrated below, every time the right foot hits the ground is one pace. Each pace (two steps) normally measures out to almost 50-60 inches.

Perhaps the best method to determine a hiker’s pace is to record it over a specific distance to determine an average.  Before embarking on the trail, the individual should develop a “pace average” over a controlled area first. 

For example, measure the number of paces for a known distance of 100 yards.  To achieve this, go to a high school foot ball field or track.  Walk along a sideline from end zone to end zone.  Count how many paces it takes to go 100 yards.  Do this eight times and record the total number of paces for each 100 yard event.  Determine the average for all eight 100 yard lengths completed.  The result is that the hiker may determine that the average 100 yard pace count to be 58 ½ paces.  (With children compensate and be mindful of their strides being significantly different, including a skip here and an off trail discovery there.)

Whatever the “pace average” may be, do keep the stride natural and smooth.  Don’t try to exaggerate and unnaturally lengthen the stride.

Don’t get too bogged down in the estimation of the accuracy of the average pace. Of larger importance is to understand the complexity of the terrain and how it will impact stride and a hiker’s “pace average”.   Anticipate strides being different.  Take the time beforehand to imitate a 100 yard course on sloping ground.  Further, try a 100 yard pace in soft soil and hard soil, smooth ground and rocky ground. Move to other locations once an average pace is found on a controlled level environment (football field).  Layout a 100 yard course on sloping ground. 

Pacing over long distance can become quite boring and the hiker easily distracted.  This is especially true when the pace count is in the hundreds.  Was that pace 545 or 554?  In such cases pacing beads may be a useful tool.  Pacing beads can be purchased from online venders or made at home using paracord and simple beads. 

 

A quick Google search will turn up several methods for using pacing beads.  For example, Wikipedia states that “As users walk, they typically slide one bead on the cord for every ten paces taken. On the tenth pace, the user slides a bead in the lower section towards the knot. After the 90th pace, all 9 beads are against the knot. On the 100th pace, all 9 beads in the lower section are returned away from the knot, and a bead from the upper section is slid upwards, away from the knot.”

Pacing beads can be an important asset when Dead Reckoning (known as DR) with a map and compass.  Vigilant compass sighting and a steady “pace average” helps provide a rough approximation of both distance and direction when moving through the backcountry.

Managing Your GPS Waypoints

Before getting too detailed lets understand just what a waypoint is.  As long as the GPS is on, it will collect information from the satellites of the GPS constellation. The receiver in your hand collects updates about once a second.  When you select "mark", that position information is automatically saved to memory; this is a waypoint. This data is the latitude/longitude of your position, your coordinates. This position information is automatically tagged with a default identification number like 001. Managing these tags is what waypoint management is all about.

Lots of things can happen to a waypoint or data file.  You can put data in. You can take data out.  You can lose it (the GPS breaks or the wrong button entry is selected.)  But be careful, too much data can make your navigation difficult.

In my land navigation class I stress keeping your navigation simple.  Frequent and simple waypoint management is essential to GPS use.  When it’s time to return to the truck, it should be obvious what waypoint to select. 

Dump the junk before the start of a trip.  A GPS receiver can store hundreds of waypoints.  I recommend that as you leave the trail head your GPS should have only necessary data saved on your GPS for that trip.  That waypoint for last year's great fishing trip is important but needs to be saved elsewhere.  

Start by deleting Waypoints that really are not needed.  Free those data bites to the atmosphere.

To save your “got to have, must save Waypoints.” 

1.       Use Garmin’s “Trip and Waypoint Manager.”  It probably came with your GPS.  It can also be purchased from Garmin for about $30.00; www.garmin.com.  Down load those Waypoints to your PC.

2.        If you don’t have the Garmin program, consider “Easy GPS.”  It is free and available at www.easygps.com.

3.        Log the important data in a notebook.

Electronic storage allows you to save waypoints and track data (that bread crumb trail on your map screen.)  Further, you can upload old Waypoints another day for a trip to that special fishing spot.  This data can also be down loaded into your friends GPS too.  It can also be uploaded to your new GPS in the future.

When you receive or transfer waypoint data always verify that you have the compatible map

datum and coordinate system set on your receiver.

Finally, give important waypoints a name.  It’s easier to remember a waypoint named  “CAMP” instead of 21 (or was it 25.)

The North Star

Polaris (the North Star) is a beacon that we can use to guide us in the backcountry. Few hikers use the celestial bodies in the night sky to navigate by.  But on a clear night, the night sky provides a feature that is an excellent source of direction.  It doesn’t matter if it is June or November, if you are in Wyoming or Oregon.

Consider that Polaris is fixed in position over the northern pole.  Unique from other celestial stars and planets, Polaris is very closely aligned to the earth’s axis.  Stars and planets rotate around Polaris.  And like the sun, this rotation is from east to west through the sky.  Polaris will be found approximately half way between the northern horizon and straight overhead.  In the northern hemisphere, Polaris can found in our northern sky and is never more 1° from true north – the North Pole. 

Constellations help locate Polaris.  Cassiopeia and the Big Dipper point to Polaris.  Uniquely, Cassiopeia, the Big Dipper and Little Dipper can be seen in relation to Polaris year round.  In winter, the constellation of Orion will also help locate Polaris.

Figure 1.  The Pointing Stars point to Polaris

In the case of the Big Dipper (above), an imaginary line is drawn from the two pointer stars to Polaris.

 Polaris will be found about at a distance of five times the space between the two pointing stars.

Another view of Polaris and adjacent constellations is seen below.

So what does this do for the hiker?

The essence is that Polaris is another visual handrail at night.  In an earlier post, I discussed the process of orienting a topographic map.  Large terrain features were identified as “backcountry handrails.” (Handrails can include roads, railroad beds, ridge lines, power transmission lines and streams.) Handrails help align the map and give the traveler a sense of relationship to the topography both on the map and what is nearby.  For example, if the hiker determines that Butler Butte will always be to the left and west of the trail then that butte becomes a visual aid for navigation. At night geographic features may not be quite so visible and distinct.  So on a clear dark night Polaris can aid the wilderness navigator by providing direction to true north.

This visual reference compliments a magnetic compass.  (Ideally the hiker uses a declination adjustable magnetic compass.)

It's always right there in the same place (even if you can't see it at the moment) and doesn't require batteries.

Cloud cover and forest canopy will limit the ability to navigate and use Polaris.  If Polaris is completely obscured but some sky is visible, attempt to find east.  Like the sun, stars and planets rotate through the sky from east to west.  Find a star and monitor its movement over a period of a few minutes.  Once you’ve determined where east is, north is to the left.

Like all navigation skills, using the night sky takes practice.  Before heading out on your next adventure, practice at home, look for Polaris at varying times. Observe the star’s relationship to the other celestial bodies.

Here is another post on the North Star from my local newspaper.

Here are a couple of good references:

• June Fleming’s book Staying Found is a fine reference about backcountry navigation. 

• Google’s Sky Map

Navigation Video's

While searching the web on land navigation I came across the Columbia River Orienteering Club's Youtube Channel.

Still going through the video's  but my first impression is that this club has done a very nice job.

Link to the club channel: Columbia River Orienteering Club.

Fitting A Back Pack Correctly

Section Hiker has a post that I recommend backcountry hikers consider.  Hikers know that a waist belt is vital to comfortable travel with a pack.  But rarely do you find information on how it should fit your waist and hips.

"When buying a backpack you want to make sure that the hip belt is long enough so that it transfers most of your pack weight off your shoulders and onto your hips so that you can use the biggest muscles in your body, your legs, to carry most of the weight."  Visit Section Hiker's site for the details.