Garmin 3 Plus Manual

							            4. A city symbol is assigned to the new waypoint, but let’s use a special symbol to identify 
it. Highlight the waypoint symbol field, using the rocker keypad, and press ENTER. Use 
UP/DOWN on the rocker keypad to select the ‘Information’ icon (‘?’) and press ENTER.
            5. To save the new waypoint, highlight ‘Done’ with the rocker keypad and press ENTER.
Now that we’ve created our new waypoint (also see pg. 47), let’s see how the GPS 
III+ is used to navigate to it. The reference arrow can also be used to GOTO any point 
on the map—even without a waypoint already at that location—by simply pressing 
GOTO.  (We won’t try that here. A waypoint named ‘MAP’ is automatically created, 
so all the previous steps for creating and naming a waypoint wouldn’t be needed. You 
might want to experiment with this procedure at the end of the Simulator Tour.) For 
the Simulator Tour, we’ll stick with the waypoint we just created.
To select the GOTO destination:
           1. Press GOTO.
            2. If the ‘All’ file tab is not selected, use the rocker keypad to highlight this tab. (‘All’ will 
display a list of all waypoints currently stored in memory.)
           3. 
Highlight the new waypoint you just created using the rocker keypad, and press ENTER.
Notice  that  a  course  line  appears  on  the  map  display  showing  the  way  to  our 
destination. Imagine you’re about to depart. Maybe you’re heading out from the marina 
or  you’re  about  to  venture  into  the  wilderness.  What  if  you  want  to  return  to  your 
present position when you’re done for the day? You have two options available:
•  You can mark your present position now and save it as a waypoint, or
•  You  can  use  the  TracBack  feature  at  the  end  of  the  day  to  retrace  your 
          steps – following the same path you travelled, but in reverse.
For  now,  we’ll  mark  our  present  position  and  save  it  as  a  waypoint.  (You  might 
want to experiment with the TracBack feature later.  It’s described on page 58.)
You can select a special 
symbol to identify the 
waypoint on the Map Page.
To select a GOTO destination, 
press GOTO and highlight the 
desired waypoint on the list. 
(You may also need to select 
the ‘All’ file tab on the GOTO 
Page, to see all waypoints 
currently in memory.)
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SIMULATOR TOUR
Going to the Waypoint 
						

							To mark your present position:
       
1.  Press and hold the ENTER/MARK key. The Mark Waypoint Page will appear, with a 
default three-digit name for the new waypoint in the upper-left portion of the page.
Let’s  call  our  present  position  ‘HOME’.  (If  you  were  at  home  when  you 
initialized  your  GPS  III+,  you  might  want  to  keep  this  waypoint  in  memory  for 
future use!)
  To rename the waypoint and change its symbol:
       
1. Use the keypad to highlight the name field, and press ENTER.
           2.  Enter the new waypoint name (‘HOME’) using the rocker keypad, and press ENTER. 
(Remember to use UP/DOWN to change the character and RIGHT to move to the 
next character field.)
           3.  Highlight the waypoint symbol field and press ENTER.
           4. Select the ‘Residence’ symbol, and press ENTER.
           5. Move the cursor to the ‘DONE?’ prompt, and press ENTER.
Now  we  have  two  waypoints  in  memory  and  on  the  map:  the  city  location  we 
saved  earlier  and  ‘HOME’.  It’s  about  time  we  get  started,  so  let’s  plug  a  speed  into 
this simulator to animate the displays!
To enter a simulated speed and animate the displays:
           1. Press PAGE repeatedly until the Compass Page appears.
           2.  Enter a simulated speed of ‘10’ (mph or knots) using the rocker keypad. (Press UP 
on the rocker keypad once to select ‘10’. The speed readout is on the upper right 
corner of the Compass Page.)
           3. Press PAGE (or QUIT) repeatedly to return to the Map Page.
To mark your present position 
and save it as a waypoint, 
press and hold ENTER. A 
three-digit name is automati-
cally assigned to the waypoint.
From the Compass Page you 
can increase/decrease the 
simulated speed using the 
UP/DOWN keys on the 
rocker keypad.
22
SIMULATOR TOUR
Marking Present Position 
						

							Notice  the  information  on  the  map  display  is  slowly  moving?  That’s  how  it  would 
look in actual use as well. The background map information and nearby waypoints will 
move across the screen, while your current position remains fixed in the center.
The  other  primary  navigation  screens  are  the  Compass  and  Highway  pages,  with 
the Compass Page appearing first in the sequence of main pages. 
To view the Compass Page, press PAGE.
The  GPS  III+’s  Compass  Page  provides  graphic  steering  guidance  to  a  destination 
waypoint.  The  middle  of  the  page  features  a  rotating  ‘compass  ring’  that  shows  your 
course over ground (track) while you’re moving, and a bearing pointer that indicates the 
direction  of  the  destination  (bearing)  relative  to  the  course  over  ground.  The  compass 
ring  and  pointer  arrow  work  independently  to  show—at  a  glance—the  direction  of 
your  movement  and  the  direction  to  your  destination.  If  the  arrow  points  up,  you  are 
going  directly  to  the  waypoint.  If  the  arrow  points  any  direction  other  than  up,  turn 
toward  the  arrow  until  it  points  up—then  continue  in  that  direction.  The  distance  to 
the  next  waypoint,  time  to  the  next  waypoint  and  current  speed    are  displayed  to  the 
right  of  the  graphic  compass  display.  To  see  how  all  this  works  on  our  simulated  trip, 
let’s head off course and watch the displays change.
To move off course / on course in simulator mode, use the LEFT/RIGHT 
keys on the rocker keypad.
The background map moves 
while keeping your current 
position at the center of the 
map display.
The Compass Page will also 
guide you to your destination. 
The rotating ‘compass ring’ 
shows the direction of travel 
(track) and the arrow points 
to your destination (bearing).
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SIMULATOR TOUR
Compass Page
Bearing
Pointer
Compass
Ring
User-selectable
data fields 
						

							To view the Highway Page, press PAGE.
The  Highway  Page  provides  a  graphic  highway  display  that  shows  your 
movement relative to the desired course. The line down the middle of the highway 
represents  your  desired  course.  As  you  navigate  toward  your  destination,  the 
highway  will  actually  move,  indicating  the  direction  you’re  off  course.  To  stay 
on  course,  simply  steer  toward  the  center  of  the  highway.  As  you  approach  the 
waypoint, the highway will end at the final destination. When the waypoint marker 
is  at  the  bottom  center  of  the  highway  display,  you’ve  arrived  at  your  destination. 
A  track  compass  also  shows  your  current  track  directly  above  the  highway  display, 
making it easy to see at a glance which way you’re headed.
The  pointer  arrow  at  the  bottom  of  the  page  indicates  the  direction  to  the 
destination  waypoint  (bearing)  relative  to  the  direction  you  are  moving  (track).  If 
the  pointer  points  straight  ahead,  you’re  heading  directly  to  the  waypoint.  If  not, 
turn  in  the  direction  of  the  pointer  and  the  pointer  will  swing  around,  pointing 
straight  ahead  as  you  begin  moving  toward  the  destination  waypoint.  Try  moving 
on  course/  off  course  again  using  the  rocker  keypad  and  watch  as  the  highway 
display and bearing pointer change.
That’s  it!  You’ve  covered  the  basics  and  you’re  ready  to  venture  off  on  your 
own.  Operating  the  GPS  III+  is  just  as  simple  as  you’ve  seen  here  in  the  Simulator 
Tour,  but  in  real  applications  you  won’t  need  to  change  speed  and  track  with  the 
rocker  keypad.  That’s  all  done  automatically  utilizing  information  from  the  GPS 
satellites as you move about.
Before  ending  the  tour,  try  a  few  experiments  of  your  own,  such  as  going 
back  to  the  ‘HOME’  waypoint,  retracing  your  steps  utilizing  the  TracBack  feature, 
or  creating  a  few  more  waypoints.  Use  the  Reference  section  of  this  manual  for 
more ideas.
Use the LEFT/RIGHT keys on 
the rocker keypad to move off 
course / on course. To return 
to your course, steer toward 
the highway centerline.
When you reach your desti-
nation, the highway will end 
at the waypoint marker. Also 
note the ‘distance to next’ 
waypoint readout. If you pass 
the waypoint the pointer will 
swing around, pointing down.
24
SIMULATOR TOUR
Highway Page 
						

							The GPS III+’s Satellite Status Page provides a visual reference of various receiver 
functions, including current satellite coverage, receiver operating mode, battery level 
and position accuracy. As the receiver locks onto satellites, a signal strength bar 
will appear for each satellite in view, with the appropriate satellite number (01-32) 
underneath each bar. The progress of satellite acquisition is shown in three stages:
•  No signal strength bars— the receiver is looking for the satellites indicated.
•  Hollow signal strength bars— the receiver has found the satellite(s) and is 
collecting data.
•  Solid signal strength bars— the receiver has collected the necessary data and 
the satellite(s) is ready for use.
Each  satellite  has  a  30-second  data  transmission  that  must  be  collected  (hollow 
bar  status)  before  that  satellite  may  be  used  for  navigation  (solid  bar  status).  Once  a 
fix has been calculated, the GPS III+ will then update your position, track, and speed 
by  selecting  and  using  the  best  satellites  in  view.  You  can  also  access  the  GPS  III+’s 
backlight and contrast feature from this page.
To adjust the screen contrast and/or backlighting:
           1.  Press LEFT or RIGHT on the rocker keypad to adjust the level of contrast, and press 
ENTER to save the new contrast setting.
           2.  Press UP or DOWN on the rocker keypad to adjust the level of backlighting, and press 
ENTER to save the new backlight setting.
Sky View and Signal Strength Bars
The sky view and signal strength bars give you an indication of what satellites are 
visible  to  the  receiver,  whether  or  not  they  are  being  used  to  calculate  a  position  fix, 
and  the  signal  quality.  The  satellite  sky  view  shows  a  bird’s-eye  view  of  the  position 
of  each  available  satellite  relative  to  the  unit’s  last  known  position.  The  outer  circle 
represents  the  horizon  (north  up);  the  inner  circle  45º  above  the  horizon;  and  the 
center point directly overhead. 
The Satellite Status Page 
shows where the satellites are 
and how strong the signal 
is from each one. A solid sig-
nal bar means the satellite is 
ready to use.
Use the LEFT/RIGHT keys on 
the rocker keypad to adjust 
the screen contrast and the 
UP/DOWN keys to adjust the 
backlighting. Press ENTER to 
save the settings.
25
REFERENCE  
Satellite Status Page 
						

							You  can  use  the  sky  view  to  help  determine  if  any  satellites  are  being  blocked, 
and  whether  you  have  a  current  position  fix  (indicated  by  a  ‘2D  Navigation’  or  ‘3D 
Navigation’ in the status field). You can also set the sky view to a ‘Track Up’ configuration, 
causing the top of the sky view to align along your current track heading.
When  the  receiver  is  looking  for  a  particular  satellite,  the  corresponding  signal 
strength  bar  will  be  blank  and  the  sky  view  indicator  will  not  be  highlighted.  Once 
the  receiver  has  found  the  satellite,  a  hollow  signal  strength  bar  will  appear,  indicating 
that  the  satellite  has  been  found  and  the  receiver  is  collecting  data  from  it.  The  satellite 
number  in  the  sky  view  will  appear  highlighted.  As  soon  as  the  GPS  III+  has  collected 
the necessary data to calculate a fix, the status field will indicate a 2D or 3D status. (For 
‘2D’, you may need to enter your altitude. See page 29.)
Receiver Status
Receiver  status  is  indicated  at  the  top  left  of  the  page.  The  status  will  be  shown 
as one of the following conditions:
  Searching— the GPS III+ is looking for any available satellites in view.
  AutoLocate—  the  GPS  III+  is  initializing  and  collecting  new  almanac  data.  This 
process can take up to 5 minutes, depending on the satellites currently in view.
  Acquiring—  the  receiver  is  collecting  data  from  available  satellites,  but  has  not 
collected enough data to calculate a position fix.
  2D Navigation— at least three satellites with good geometry have been locked onto 
and  a  2-dimensional  position  fix  (latitude  and  longitude)  is  being  calculated.  ‘2D 
Diff ’ will appear when you are receiving DGPS corrections in 2D mode.
  3D Navigation— at least four satellites with good geometry have been locked onto, 
and  your  position  is  now  being  calculated  in  latitude,  longitude  and  altitude.  ‘3D 
Diff ’ will appear when you are receiving DGPS corrections in 3D mode.
‘2D Navigation’ means the 
GPS III+ has determined a 
horizontal position (latitude/
longitude), but is unable to 
determine altitude. Additional 
satellites may be needed.
‘3D Navigation’ means the 
GPS III+ has determined 
a horizontal and vertical 
position (latitude, longitude 
and altitude). The receiver is 
ready for navigation.
26
REFERENCE  
Satellite Status Page 
						

							  Poor  GPS  Coverage—  the  receiver  isn’t  tracking  enough  satellites  for  a  2D  or 
3D fix due to bad satellite geometry.
  Not  Usable—  the  receiver  is  unusable,  possibly  due  to  incorrect  initialization 
or  abnormal  satellite  conditions.  Turn  the  unit  off  and  back  on  to  reset,  and 
reinitialize the receiver if necessary.
  Simulating Nav— the receiver is in simulator mode.
‘Need to Select Initialization’ Prompt
If  no  satellites  are  received  for  several  minutes  (or  an  insufficient  number  of 
satellites  are  received  to  determine  a  position  fix)  a  message  will  appear,  prompting 
you  to  initialize  the  receiver  (see  page  5).  This  allows  you  to  specify  a  starting 
location  from  which  to  search  for  satellites,  or  to  enable  the  AutoLocate  feature,  and 
is useful if you have traveled over 500 miles with the receiver off. (This message will 
automatically  appear  when  you  first  use  your  GPS  III+.  The  prompt  may  also  appear 
during normal use if the antenna is shaded or the unit is used indoors.)
Battery Level Indicator
The Satellite Status Page also features a battery level indicator, located to the left of 
the sky view, which displays the strength of the unit’s batteries. The battery indicator 
will not appear if the receiver is operating on external power.
NOTE:  The  battery  level  indicator  is  calibrated  for  alkaline  batteries.  NiCad  and 
lithium batteries will display the battery level differently due to voltage differences. To 
display  battery  level  accurately  select  the  appropriate  type,  as  described  on  page  77. 
The GPS III+ features an internal 10-year lithium battery that will maintain the unit’s 
memory when the receiver is not running off batteries or external power.
‘Poor GPS Coverage’ means 
the receiver isn’t tracking 
enough satellites for a position 
fix. Check for obstructions, 
such as trees, buildings, etc.
This message appears if a 
position fix cannot be deter-
mined after several minutes. 
After acknowledging the 
message, select ‘Use Map’ 
or ‘AutoLocate’ from the 
options list.
27
REFERENCE  
Satellite Status Page
H 
						

							‘AutoLocate’ forces the receiv-
er to search for all satellites 
(twelve at a time) until 
enough satellites are found to 
determine a position.
EPE and DOP
The  Satellite  Status  Page  also  indicates  the  accuracy  of  the  position  fix,  using 
Estimated  Position  Error  (EPE)  and  Dilution  of  Precision  (DOP)  figures.  DOP 
measures satellite geometry quality (i.e., number of satellites received and where they 
are relative to each other) on a scale from one to ten. The lowest numbers are the best 
accuracy  and  the  highest  numbers  are  the  worst.  EPE  uses  DOP  and  other  factors  to 
calculate a horizontal position error, in feet or meters.
Satellite Status Page Options
Many  features  of  the  GPS  III+  are  menu  driven.  Each  of  the  main  pages  has 
an  options  menu,  allowing  you  to  custom  tailor  the  corresponding  page  to  your 
preferences and/or select special features which specifically relate to that page.
To display the Satellite Status Page Options, press MENU (with the 
Satellite Status Page displayed).
The following Satellite Status Page options are available:
  Start Simulator— allows you to activate the GPS III+’s built-in simulator mode. If  
‘Start Simulator’ is selected, ‘Stop Simulator’ will appear as an option instead.
To activate (deactivate) simulator mode:
           1. Highlight ‘Start Simulator’ (or ‘Stop Simulator’) and press ENTER.
           2. Highlight ‘Yes’ and press ENTER.
  Tr a c k   U p—  changes  the  sky  view  display  from  ‘North  Up’  orientation  to  align 
to  current  direction  of  travel  (track).  If  ‘Track  Up’  is  selected,  ‘North  Up’  will 
appear as an option instead.
To change the sky view orientation:
           1. Highlight ‘Track Up’ (or ‘North Up’) and press ENTER.
The Satellite Status Page 
Options allow you to enable 
the built-in simulator, change 
the sky view orientation or 
initialize the receiver.
28
REFERENCE  
Satellite Status Page 
						

							With 2D coverage, you will 
need to enter your approx-
imate altitude. Without an 
approximate altitude, your 
position error can be sub-
stantial.
  AutoLocate—  forces  the  GPS  III+  to  search  for  any  available  satellite(s)  to 
determine  its  position.  This  option  is  useful  if  you’ve  relocated  a  long  distance 
(>500 miles) from the last location the GPS III+ was used.
To select AutoLocate, highlight ‘AutoLocate’ and press ENTER.
Initialize Position— allows you to designate your approximate position in order 
       to  speed  up  satellite  acquisition.  This  option  may  be  used  in  lieu  of  ‘AutoLocate’, 
       above.
To initialize your starting position:
           1. Highlight ‘Initialize Position’ and press ENTER.
           2. Designate your approximate position on the map using the rocker keypad and press 
              ENTER. (You may wish to use the IN/OUT zoom keys to adjust the level of detail
              displayed, as you determine your approximate position.)
Set  2D  Altitude—  allows  you  to  designate  your  approximate  altitude,  when  the 
       GPS  III+  is  acquiring  satellites  or  navigating  in  2D  mode.  By  default,  2D  naviga-
       tion  will  attempt  to  use  the  last  known  altitude.  If  the  altitude  shown  is  off  by 
       several  hundred  feet  (or  more),  manually  entering  your  approximate  altitude  will 
       enable the receiver to more accurately determine a position fix. 
To enter an altitude:
           1. Highlight ‘Set 2D Altitude’ and press ENTER.
           2. Enter your approximate altitude using the rocker keypad, and press ENTER.
‘Initialize Position’ is used to 
designate your approximate 
position directly on the map 
display. The receiver uses 
this information to determine 
which satellites should be in 
view.
29
REFERENCE  
Satellite Status Page Options 
						

							The Position Page shows you 
where you are, what direction 
you’re heading and how fast 
you’re going.
30
REFERENCE  Contrast and Backlighting
On  page  25,  we  introduced  display  contrast  and  backlighting  adjustments 
accessible from the Satellite Status Page. Display settings can also be adjusted from any 
page, by pressing the red power key. When backlighting is on, a bulb icon will appear 
on the Satellite Status Page, to the bottom left of the sky view. To adjust the duration 
of the screen backlighting, refer to the operation setup section (see pg. 77). 
To adjust the screen contrast and/or backlighting from any page:
           1.  Press the red power key momentarily. A window will appear showing the current 
contrast and backlighting settings.
           2.  Press LEFT or RIGHT on the rocker keypad to adjust the level of contrast, and press 
ENTER to save the new contrast setting.
           3.  Press UP or DOWN on the rocker keypad to adjust the level of backlighting, and press 
ENTER to save the new backlight setting.
Position Page
The  second  page  in  the  GPS  III+’s  main  page  sequence  is  the  Position  Page. 
This  page  shows  you  where  you  are,  what  direction  you’re  heading,  and  how  fast 
you’re going, and it’s most useful when you are traveling without an active destination 
waypoint.  The  graphic  heading  display  at  the  top  of  the  page  indicates  the  direction 
you’re heading, or track, only while you’re moving.
Directly below this display are the speed, average speed, trip timer, trip odometer 
and  sunrise/sunset  fields  (default).  The  sunrise/sunset  times  indicated  are  for  your 
present  position.  These  times,  and  the  current  time  display  in  the  lower-right  corner, 
can  be  displayed  in  local  or  UTC  (universal)  time.  The  lower  left-hand  corner  of  the 
page shows your current latitude and longitude in degrees and minutes (default). The 
GPS  III+  uses  this  basic  information  to  mark  exact  positions  as  waypoints,  which 
help guide you from one place to another. Average speed, sunrise and sunset times (at 
Contrast and Backlighting
When screen backlighting is 
on, a bulb icon will appear 
in the lower-left corner of the 
Satellite Status Page.