GPS Handheld Unit Operation

1
GPS Handheld Unit Operation
Images from Garmin RINO 520 manual
2
GPS Basics

• GPS receivers (such as the handheld units) detect
  signals from orbiting satellites.
• Once the receiver has signals from enough
  satellites, a position on the earth can be
  calculated.

3
GPS Accuracy
Accuracy Specifications for the RINO 520

• The Garmin Rino 520 units we will be using have a
  minimum accuracy of 49 ft.
• Wide Area Augmentation System (WAAS) correction
  can be used to increase accuracy to at least 10
  ft for the handheld units. Often it is within 2
  feet.
• WAAS correction will be turned on for the contest.

4
Signal Acquisition

• All GPS systems require some time to begin
  positioning.
• This time is required to acquire satellite
  signals.
• The time can vary from 15 seconds to 5 minutes.
• If a receiver has been operating in an area it
  will remember the positions of satellites and
  will not require much time to acquire signal.
  This starting the receiver warm.
• The units at the contest will be starting warm
  and will require about 15 30 seconds.

5
Handheld Unit Operation

• The GPS unit will start at a main display page
  when turned on.
• For the contest, this page can provide you
  directional data to compare locations at the
  site.
• The compass feature will only show the direction
  of travel when the unit is moving. If you are
  stationary it cannot tell you what way you are
  facing.
• This page can be used to determine the relative
  positions of the locations, but there is a better
  way to do this.

6
Adding Waypoints

• A waypoint marks a location for future reference.
  
• By marking a waypoint on the GPS unit, the
  Latitude and Longitude will be displayed.
• This data will be needed to determine the
  Latitude and Longitude of the locations.

7
Adding Waypoints continued

• The directions to add a waypoint are out of the
  manual for the Garmin RINO 520. The manual is
  online at http//www.garmin.com/manuals/915_Owner
  sManual.pdf
• It is recommended you familiarize yourself with
  the process and look at manual to find the button
  locations.

8
Measuring Distance

• After adding a waypoint the distance to that
  waypoint will be displayed at the bottom of the
  screen.
• Walk to the next location with this screen still
  active and the distance and direction from your
  current location will be displayed at the bottom.
  
• This is an easier method than using the compass
  feature.

9
Contest Considerations

• Remember what waypoint corresponds with which
  location. It is probably best to keep waypoint
  names the same as the location numbers.
• Other GPS units can be used, but you will need to
  be familiar with the unit before the contest.

10
Practical Example

• Assume the dots are field tile inlets and you
  need to know what the distance between each inlet
  is and how far from the outlet it is.
• You could start at any of the inlets and place a
  waypoint. Then travel to the next inlet.
• At the next inlet you would read the direction
  and distance from the last waypoint(inlet).