Map, Compass & GPS

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

Wednesday, May 25, 2016

Improving GPS Accuracy

There are only a few things the hiker can do to improve GPS accuracy.
The first step is to go to the Satellite Information page.  Ideally at least 4 of the green icons will be displayed.  The green icons represent satellites being tracked.  It is critical to have no less than 4 satellites for GPS accuracy. 
Next, make sure that the receiver is not in the DEMO mode.  In DEMO mode no satellites will be tracked.  To regain GPS accuracy go to the main menu>select SETUP>select SYSTEM>select GPS; see below.
Once the GPS receiver is correctly set up the hiker will begin to track satellites almost immediately.
To further improve GPS accuracy insure the Wide Area Augmentation System (WAAS) option is enabled.  WAAS will improve accuracy to +/- 3 meters.  WAAS can be enabled from the same screen that DEMO was removed.  Notice the letter D on the satellite information page indicating signal reception; see the image below.
If the WAAS correction can’t be received the GPS will be accurate to +/- 15 meters.

More informaition relating to GPS Accuracy.




Monday, May 23, 2016

GPS Accuracy

Are you comfortable with the accuracy of your GPS receiver?  
The package says that your Global Positioning System (GPS) receiver is accurate to +/- 15 meters and some advertise +/- 3 meters.  Just what does that mean to you?
Accuracy depends on several things, most of which are beyond your control.  For example, it is reasonable to expect a new GPS with the latest antenna, circuitry, processor capability and memory technology will perform better than one made in 2005.  The number of satellites signals a receiver acquires helps too; you’ll need at least four.
The graphic below tells an interesting story.  Through the center of the topographic map, marked with dashed lines is the Pacific Crest Trail (PCT) in Oregon’s Cascades mountain range.  Next to the trail is my track log (in red) downloaded from my GPS to my Terrain Navigator software.  The track log is my electronic path calculated by the receiver.
I walked on the PCT the entire time.



  My GPS receiver was in a holster attached to the shoulder straps of my backpack.  The receiver’s antenna was exposed but only received data from my front and straight up, my chest blocked signals from behind my back.

As the green of the map indicates I was in a forested area. Tree canopy was moderately thick and may have interfered with signal reception.

Further, I was on the move the entire time, stopping only occasionally.
Obviously, there is a distinct difference between the map and the track log. 

To improve the accuracy of my track information I could do three things.  First, I would have removed the receiver from the holster.  Second, I could have moved into an area clear of forest canopy. Third, I would give the GPS time to develop good satellite tracking information.

I have found that with older receivers moving out from underneath canopy and giving the unit time to calculate position data is extremely important.  A new Garmin 62 might have accurate position information in less than 20 seconds while an older Garmin Map60CS might take a minute.

Many people tend to think that a GPS receiver pinpoints their position exactly where they are standing all the time.  A hiker’s position is within the diameter of the specifications of the model.  If a receiver is accurate to +/- 15 meters (a radius) the unit’s calculated position will be somewhere inside the 30 meter diameter of a circle.  The accuracy could improve. 
In my GPS classes I recommend to my students to consider that they are traveling down a lane in the backcountry.  The size and width of the lane might grow or shrink depending on the number of satellites received and if terrain is blocking signals.

Test your receiver’s accuracy at home.

Find a quiet street or side walk to view how position accuracy changes.  Ideally it will be oriented true north and south.  Using your GPS receiver and compass, walk true north and look at your latitude and longitude.  Because lines of longitude are also oriented true north and south that data shouldn’t change.  Walk about 100 yards; again going true north.  Observe how much the longitude coordinates change.  Maneuver to stay on the original longitude and see how far off you’ll have to wander from your planned track.

Read more about GPS receivers. and their accuracy.accuracyl




Friday, May 20, 2016

Handrails

In a previous post I discussed the concept of terrain association.  Terrain association is the process of visually confirming a map to land features.

A subset of terrain association is the use of handrails.  Handrails are linear features found on a map and visually correlated to observed land features.  As in a building, a stairway’s handrail provides direction for a walkers travel down to another level.

Examples of handrails include roads, rivers, trails and railroad beds.  Handrails can be particularly useful when they run parallel to ones’ direction of travel.



Highway 126 and Cache Creek are distinct linear features that could serve as a handrail.
In the map above notice that the red direction of travel line parallels Highway 126. 

In this example Highway 126 could also be a backstop to alert the hiker that crossing the roadway would take them in the wrong direction.

Be alert for a handrail’s change of direction.  There may be prominent land features that will alert the backcountry traveler to such a change.  A butte or building might be adjacent or near to a change in direction. 


Wednesday, May 18, 2016

10 Essential Food Items Necessary for Survival

Post by Lee Flynn

 
If there were ever an emergency, then the first 10 items anyone would want in bulk would be the 10 items below in the list. They have been selected carefully for a number of reasons. They're easy to store, and many of them are essential nutritionally. Here are 10 foods absolutely necessary for an emergency food plan.

 

25 Pounds of a Variety of Rice

oats.jpeg 

Rice is a must have in, and it should be at the top of the list for anyone starting in food storage planning. 25 pounds is a lot of rice, but it may be necessary. Rice is nutritious and filling, and once the plan begins to expand, then other items can be added to the inventory to make the rice more appetizing. It is recommended to get a combination of white and brown rice. This is because of the health benefits of brown rice and the longer shelf life of white rice. It is a staple to have in the grain group, especially since it is important to still cover the four food groups.

At Least 25 Cans of Vegetables

 

Do not let taste and preference be the guide hand when selecting vegetables. There needs to be a mix of different kinds vegetables in this plan for a very good reason, which is nutrition. Certain vegetables offer certain important vitamins, nutrients and antioxidants. Mix this selection up with greens, carrots, canned potatoes and anything else available different from the rest.

 

25 Cans Minimum of Various Fruit

 

Canned fruit usually comes in a sweet syrup, and it tastes pretty good too. Aside from the taste, the selection of fruit should be varied like the vegetables for the same reason. Get a variety to cover as many different vitamins and nutrients as possible, and the sugar in fruit is also good fuel for the body. The idea behind the variety of fruit and vegetables is stave off any nutritional deficiencies.

Five Pounds of Oats

 

Oatmeal is packed with nutrition and fiber. Fiber is extremely good for the human body. Besides keeping us regular, it slows down the absorption of glucose in the flood, and it will help prevent crashing, and it's good for people with diabetes or during pregnancy  according to Healthline which is an equally important thing to consider when preparing for emergencies even if you are planning for newborn adoption. It is also very filling in small amounts.

 

25 Cans of Various Meat

 

All kinds of meat come available in a can like shrimp, salmon, clams, tuna, chicken, beef stew and even those little Vienna sausages and Spam. Again, try and go for a variety, but the main reason for meat on the shopping list is protein. Protein is essential to live, and it repairs cells and builds muscle. Any kind of injuries sustained by someone will need protein to heal.


Five Pounds of Powdered Milk

 

Milk is on the list for a couple of reasons, and it also completes the food groups. Milk is full of nutrients and protein, and it is also a great source of Vitamin D, which will be vital in case having to stay out of the sun for awhile is necessary. It can also be added to oatmeal and other grains.

 

Three Large Jars Powdered Fruit Drink Mixes Fortified With Vitamin C

 

This will add some flavor to an unfortunate situation, and the Vitamin C fortification helps boost the immune system, and depending on how long the food plan is necessary, Vitamin C is something no one wants to be deficient in. DermNet NZ warns a Vitamin C deficiency could result in the old affliction of scurvy.

Five Pounds of Salt

 

Salt is a must when making a food prepping list. It is perfect for enhancing flavor, preserving food and it prevents the sodium deficiency of Hyponatremia, which has some very nasty symptoms. Salt is a necessary part of the human diet.


Five Pounds of Dried Pasta

 

This is filling, and it is a comfort food. A comfort food is something to be cherished if an emergency ever occurs.

Five Large Jars or Cans of Pasta Sauce

 

There is no scientific explanation for this item, but it does go well with the pasta, and it is an easy way to make a filling meal.

 

The basic food groups have been taken care of, and everything has a large, reasonable amount to be purchased and stored. This list is put together with nutritional deficiencies in mind. It was also meant to balance nutrition with taste and comfort. It is never too late to prepare for an emergency.




Lee Flynn is a freelance writer. Through small local workshops and articles, Lee trains and teaches others on home preparation, healthy living, food storage techniques, and self reliance.


Click for his  Google+