Magellan NAV 5000 User Manual
MAGELLAN GPS
NAV 5000
TM
USER GUIDE
Magellan Systems Corporation
960 Overland Court
San Dimas, California 91773
(714) 394-5000
FAX (714) 394-7050
No part of this User Guide may be reproduced or transmitted in any
form or by any means, electronic or mechanical, including photocopying and recording, for any purpose other than the purchaser's personal
use, without the written permission of Magellan Systems Corporation.
© Copyright Magellan Systems Corporation, 1991. All rights reserved.
MagellanTM, GPS NAV 5000TM , and InstafixTM are the trademarks of
Magellan Systems Corporation.
Part No. 22-10029-000
WARNINGS
A measure of knowledge by the user is required for proper and safe
use of the
WARRANTY COMPLETELY.
This product is an excellent navigation aid, but it does not replace the
need for careful orienteering and good judgement. Never rely solely
on
one device for navigating.
The Global Positioning System (GPS) is operated by the U.S. Government, which is solely responsible for the accuracy and the maintenance of GPS. Certain conditions can make the system less accurate,
such as changes in the orbit or health of a satellite.
Accuracy can also be affected by poor satellite geometry. WHEN THE
ACCURACY WARNING APPEARS ON THE SCREEN, USE THIS
DATA WITH EXTREME CAUTION.
Magellan GPS NAV 5000TM.
READ THE USER GUIDE &
Use Good Judgment
Use Care to Avoid Inaccuracies
THE GLOBAL POSITIONING SYSTEM IS STILL DEVELOPMENTAL.
The government can make changes to the system which could affect
the performance of GPS receivers. Such a change could require a
modification to your NAV 5000.
tion/Warranty card to Magellan, you will have the opportunity to
upgrade your unit and/or software.
lf you have returned the Registra-
Throughout this User Guide, the pattern graphic/graphic/text is used to
explain and describe the key sequences used to operate the unit.
Specifically, the keys pressed are shown, followed by the screen as it
appears after the keys are pressed. The text repeats the instructions
that were described graphically.
Reading the Guide
NOTE:
li
mits for a Class B digital device, pursuant to Part 15 of the FCC
Rules. These limits are designed to provide reasonable protection
against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if
not installed and used in accordance with the instructions, may cause
harmful interference to radio communications. However, there is no
guarantee that interference will not occur in a particular installation. If
this equipment does cause harmful interference to radio or television
reception, which can be determined by turning the equipment off
on, the user is encouraged to try to correct the interference by one or
more of the following measures:
—
—
—Connect the equipment into an outlet on a circuit different from that
—
This equipment has been tested and found to comply with the
and
Reorient or relocate the receiving antenna.
Increase the separation between the equipment and receiver.
to which the receiver is connected.
Consult the dealer or an experienced radio/TV technician for help
.
TABLE OF CONTENTS
CHAPTER 1
The NAV 5000
The GPS System
Data Transmission
How a Position Fix is Obtained
I
nterference
Monitoring and Controlling GPS
Specifications
Packing List
Accessories
Carrying Case
Quick-Release Bracket Mounting Kit
...............................................................................
........................................................................... 1-2
.................................................................
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................................................................................
...................................................................................
...................................................................................
........................................................................
CHAPTER 2
-
-
GETTING READY TO USE
YOUR NAV 5000
Batteries
........................................................................................
Loading Alkaline Batteries
Battery Operation
Battery Warning
...................................................................
.....................................................................
..................................................... 2-1
INTRODUCTION
1-1
1-2
.............................................. 1-2
1-3
............................................
..................................... 1-8
1-3
1-5
1-7
1-7
1-8
2-1
2-3
2-3
External Power Operation
Power Adapters
Connecting to an External Power Source
Initialization
Orienting the Antenna
Collecting an Almanac
Connecting to an External Device (NMEA)
NMEA Pin Positions
....................................................................................
............................................................
..................................................................... 2-4
..................................................................
.................................................................. 2-10
..................................
...............................................................
i
..............................
2-3
2-4
2-5
2-9
2-13
2-13
NMEA Setup
Activating NMEA Support
..........................................................................
......................................................
2-14
2-14
Entering Data
...............................................................................
CHAPTER 3 - BASIC OPERATION
Obtaining a Position Fix
Entering a Waypoint
Saving a Position
Entering a Position Manually
Setting a Route
Getting Velocity
Getting Navigation Data
Determining the Quality of a Fix
Signal Quality
Geometric Quality
Dated Information
Adjusting Display Brightness
Obtaining Information on the Satellites
Satellite Status
Satellite Schedule
.............................................................................. 3-5
.............................................................................. 3-7
............................................................... 3-1
....................................................................... 3-3
...................................................................
................................................. 3-4
.................................................................
................................................... 3-9
......................................................................... 3-9
...................................................................
......................................................................
........................................................
.......................................................................
...................................................................
......................................
2-14
3-3
3-7
3-9
3-10
3-10
3-11
3-11
3-12
Supporting NMEA Devices
...........................................................
CHAPTER 4 - FUNCTION KEYS
Last Fix
Light
Navigation
..........................................................................................
The Last Fix
Last Fix Backups
...............................................................................................
...........................................................................
....................................................................
.....................................................................................
ii
3-13
4-1
4-1
4-2
4-4
4-4
On/Off
............................................................................................
Self-Test
Power Warnings
4-7
.................................................................................. 4-8
.....................................................................
4-8
Position (POS)
Taking a Position Fix
Position Display
Continuous Operation
Real - Time Messages
Search and Acquisition Errors
Insufficient Number of Satellites
Unit Searches Constantly
Initialization Error
Accuracy Warning Symbol
Signal Quality
Old Data
Route
.............................................................................................
Multi-Leg Routes and NMEA
Creating a Route
Viewing an Existing Route
Resetting a Route
Route Modes
Automatic Mode
Manual Mode
SETUP
Entering an Initialization Position
Setup Worksheet
Selecting Mode and Altitude
Setting the Time
Choosing Automatic or Manual Route Mode
Choosing Lat/Lon Display
Selecting a Defined Map Datum
Setting a User-Entered Map Datum
Magnetic Variation Display
Distance/Speed Units
Altitude Units
Date Order
...............................................................................
.............................................................. 4-10
..................................................................... 4-12
............................................................
...........................................................
............................................... 4-15
............................................
......................................................
...................................................................
..................................................... 4-17
......................................................................... 4-17
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....................................................................
.....................................................
..................................................................
..........................................................................
.....................................................................
..........................................................................
..........................................................................................
...........................................
...................................................................
.................................................. 4-30
..................................................................... 4-32
.........................
...................................................... 4-34
............................................
.......................................
.................................................... 4-38
............................................................ 4-39
..........................................................................
..............................................................................
4-10
4-14
4-14
4-15
4-15
4-16
4-18
4-18
4-19
4-20
4-22
4-22
4-22
4-24
4-25
4-26
4 27
4-28
4-33
4-35
4-36
4-40
4-41
Velocity
..........................................................................................
iii
4-41
Waypoints
......................................................................................
Saving Positions as Waypoints
Entering Waypoints Manually
Viewing Stored Waypoints
Renaming Waypoints
Clearing a Waypoint
CHAPTER 5
.............................................................
...............................................................
AUXILIARY FUNCTION KEYS
-
..............................................
................................................
.....................................................
4-42
4-42
4-44
4-46
4-47
4-48
AUX 1 — Receiver Status Screen
AUX 2 — Display Control
AUX 3 — Satellite Status
.......................................................
.......................................................
AUX 4 — Satellite Schedule
AUX 5 — Sky Search
AUX 6 — NMEA Setup
AUX 7 — Beeper Control
.............................................................
..........................................................
.......................................................
AUX 8 — Waypoint Projection
AUX 9 — Battery Saver
.........................................................
AUX 10 — Erase Waypoints
AUX 13 — Clear Memory
......................................................
.........................................
..................................................
...............................................
..................................................
Table of Auxiliary Functions, in Alphabetical Order
CHAPTER 6
TROUBLESHOOTING AND
-
OPERATING TIPS
Error and Warning Messages
Operating Problems
Display Frozen
No Power
.....................................................................
.......................................................................
...............................................................................
Unit Turns Off During Use
Position Fix Doesn't Change
Fixes Vary a Lot
.....................................................................
External Devices Not Responding
Autopilot Does Not Respond
Nav Does Not Work
Dashes Appear in NAV Displays
Zeroes Appear in POS, NAV, and VEL Displays.
Satellite Availability Not To Your Expectations
.......................................................
......................................................
.................................................
........................................
.................................................
...............................................................
..........................................
.....................
...............
.................
5-2
5-3
5-3
5-6
5-8
5-9
5-10
5-11
5-12
5-13
5-14
5-16
6-1
6-5
6-5
6-5
6-6
6-6
6-7
6-8
6-8
6-9
6-9
6-9
6-9
Operating Tips
General
..................................................................................
..............................................................................
iv
6-11
6-11
Unsure of Your Initialization Position
.....................................
6-11
Choosing a Datum
Using the Unit Near the Poles
Storing the Unit
For More Than 3 Months
For Less Than 3 Months
When Nothing Else Works
Magellan Customer Support
........................................................................
......................................................
..............................................................................
.......................................................
........................................................
...........................................................
.........................................................
APPENDICES
Appendix 1 — Waypoint Log
Appendix 2 — Table of Constants
Appendix 3 — Geometric Quality
Appendix 4 — Signal Quality
Appendix 5 — Function Key Sequences
Appendix 6 — Glossary
........................................................
................................................
.................................................
........................................................
......................................
................................................................
INDEX
6-11
6-12
6-12
6-12
6-13
6-13
6-13
A-1
A-3
A-13
A-14
A-15
A-19
v
CHAPTER 1
INTRODUCTION
This chapter contains a description of the NAV 5000, its specifications
and accessories, and the Global Positioning System (GPS).
THE NAV 5000
The NAV 5000 is an affordable, hand-held GPS receiver that is fast,
powerful, and accurate, yet very easy to use. The NAV 5000 uses five
channels working simultaneously to locate and collect data from the
GPS satellites. The unit's gallium arsenide circuitry rapidly processes
data received from the satellites to compute current location (LAT/
LON), altitude, and velocity and navigation data in under 1 minute, and
updates the data every second.
The NAV 5000 can be set to use any of three modes to calculate
positions: two-dimensional (2D), three-dimensional (3D), and the
Automatic (AUTO) Mode. In 2D, the unit uses 3 satellites to calculate
latitude and longitude: altitude is a user-entered variable. In 3D, the
unit uses 4 satellites to calculate latitude, longitude, and altitude. In the
Automatic Mode, the unit uses 3D whenever 4 satellites are available;
when only 3 satellites are available, the unit switches to 2D.
the
The NAV 5000 also stores an initial position, last fix, the four
recent fixes, and up to 100 waypoints that are created by the user.
Most of these positions can be used to enter a route and to estimate
the coordinates and bearing of a distant location.
The NAV 5000 was developed primarily for marine use. lt supports
most devices that conform to NMEA (National Marine Electronic
Association) standards 0180 or 0183. This includes devices such as
autopilots, plotters, and sounders.
Though a fast, powerful navigation tool, the NAV 5000 is very easy to
use. Most functions can be accessed by pressing only one clearly
marked key. Other functions, such as the NMEA control and Sat
Status, are accessed through the auxiliary keys.
most
1-1
THE GPS SYSTEM
The Global Positioning System (GPS) is a highly accurate, worldwide
navigation and positioning system that can be used 24 hours a day.
Designed at the impetus of the US Department of Defense and prima
ly for military use, GPS is available to a variety of users worldwide,
including recreational boaters, fishing and shipping fleets
commercial aviation, surveyors, and engineers.
The system is based on a constellation of satellites that, when complete, will consist of 21 satellites and 3 working spares orbiting the
Earth twice a day in six orbital planes. Each satellite is in a fixed orbit
approximately 10,900 nautical miles above the Earth, and inclined at
55 degrees from the equator.
Data Transmission
Each satellite continuously transmits two types of orbit data: Almanac
and Ephemeris. Almanac data contains the health and approximate
location of every satellite in the system. Ephemeris data contains the
precise orbital parameters of each satellite. A GPS receiver gathers
Almanac data from any available satellite; using information from the
Almanac, the receiver then determines which set of satellites will give
the best geometries for a position fix.
The satellites also transmit two codes. The encrypted code (P-Code) is
the more accurate of the two, and is reserved for military use.
, general and
ri-
The unprotected code (Coarse Acquisition, or C/A Code) is intended
for public access. lt is also used to determine the precise range of the
user from each satellite, which is the first step in calculating a position
fix.
All transmissions from the satellites are in real time.
How a Position Fix is Obtained
Navigation with the Global Positioning System and a well-designed
GPS receiver is very simple. The receiver uses data collected from
three or four satellites to solve a fundamental geometric equation and
presents it in navigation displays.
First, the unit determines which satellites to use to obtain the position
fix and then the receiver obtains Ephemeris data from those satellites.
(Three satellites are used in 2D; a fourth satellite is used in 3D to
determine altitude.)
1-2
THE GLOBAL POSITIONING SYSTEM
The receiver then assesses the transmission time and signal quality
from each satellite, and multiplies the difference in the transmission
time by the speed of light (186,000 miles per second) to arrive at an
estimate of the satellite's distance from the receiver (range). Next, the
unit calculates (by triangulation) and displays the position fix.
Although accuracy varies slightly with satellite constellation geometry,
a position fix accuracy of 25 meters or better is typical with C/A Code
receivers.
Interference
GPS uses a high frequency radio signal (1575.42 MHz) that operates
in a wave environment where there is little interfering radiation. Also,
GPS uses spread spectrum technology to protect its navigation signals. The GPS signal is therefore extremely resistant to conditions that
disturb other electronic navigation systems. In general, weather
conditions, on-board electronics, passing ships, on-shore electronic
installations, on-board engine ignition, and portable radio receivers do
not affect the GPS signal.
Monitoring and Controlling GPS
GPS is operated by the US Air Force from a master control station in
Colorado, USA. The facility is equipped for satellite monitoring, telemetry, tracking, command and control, data uploading, and navigation
message generation.
1-3
Monitor stations and ground antennas throughout the world passively
track the GPS satellites and relay data to the master control station.
Exact satellite position and signal-data accuracy can therefore be
constantly updated and maintained. Minor discrepancies between
where the satellite "thinks" it is and where the monitor station "knows" it
is can also be adjusted.
lf any satellite emits erroneous data or is otherwise not operating
properly, a ground station marks it "unhealthy." The affected satellite
broadcasts its status to the GPS receiver, which is programmed to
ignore an unhealthy satellite and use the next best satellite to obtain a
position fix.
The master control station can selectively degrade satellite data. This
degradation, or Selective Availability (SA), can cause positioning errors
of 100 meters (2D RMS).
DISPLAY
SCREEN
ANTENNA
FUNCTION
KEYS
ALPHANUMERIC
KEYPAD
GPS RECEIVER
1-4
SPECIFICATIONS
Physical Characteristics
Unit Size:
3.5" x 8.75" x 2.13" (excluding antenna);
(13.8 cm x 34.5 cm x 8.4 cm)
5.0" x 9.0" x 2.5" (bracket-mounted)
(19.7 cm x 35.4 cm x 9.8 cm)
Weight:
Display:
LCD Dimension:
LCD Operating
Temperature:
Case:
Buoyancy:
Safe Storage
Temperature:
GPS Exterior Antenna:
30 ounces (.85 kg) with batteries
4 line, 16 character, alphanumeric, backlit
LCD
2.56" x 1.77" (6.5 cm x 4.5 cm)
0.28" (0.70 cm) high digits (w/cursor)
-10°C to 60°C
Waterproof (Battery Compartment is
splashproof.)
Specific Gravity compared to seawater =
0.8 (it floats)
-40°C to 70°C
3.5" (8.89 cm) diameter x 3.5" (8.89 cm)
height, plus 50 feet (15.24 meters) of
cable. (Part of Quick-Release Bracket
Mounting Kit.)
Data Characteristics
Accuracy:
Position — 15 meters RMS in 2D. (Accuracy of fixes can be affected by the
periodic adjustments to GPS satellites by
the US Government, and is subject to
change in accordance with the Department of Defense Civil GPS user policy.)
Velocity —±0.1 Knots (HDOP<2,
>47 dB-Hz, 2D)
C/N
o
1-5
Velocity:
0 to 825 Knots (0 to 951 mph)
Time to First Fix:
Update Rate:
Memory:
Modes of Operation:
Electrical Characteristics
Power Requirements:
55 seconds typical (cold start)
35 seconds typical (warm start)
1 second (2D) typical
100 user-stored waypoints, initial position,
and 5 last fixes
2D (solves for LAT, LON, and time with a
user-entered altitude using best 3 satel
OR
3D (solves for LAT, LON, Attitude, and
me using best 4 satellites)
ti
OR
Automatic (uses 2D or 3D, depending on
number of available satellites.
6 AA alkaline batteries (internal), 10 to 15
DC with adapter
v o l t s
lites)
Power Consumption:
115 volts
160 mA without backlight
185 mA with backlight
AC±10%, with adapter
1-6
PACKING LIST
When you receive your NAV 5000 Basic Package, you should have all
the following:
o
Magellan Nav 5000 unit, 1
Battery Clips, 2 —1 in unit and 1 spare
o
Batteries, 6 — in unit
o
Lanyard, 1
o
o
Field Card, 1
o
User Guide, 1
o
Warranty/Registration Card, 1
o
Faststart
lf any of these items is missing, contact your dealer.
NAV
of
5000
MAGELLAN GPS NAV 5000
ACCESSORIES
The NAV 5000 has several accessories, including spare battery clips
and power adapters. The two most commonly used accessories are
described below. All accessories for the NAV 5000 are available from
your Magellan dealer.
1-7
Carrying Case
The sturdy carrying case, illustrated below, holds the unit, an extra
clip, and the field card. The case can be worn over the shoulder
belt, and is an excellent storage container when the unit is
NAV 5000 CARRYING CASE
or on your
not in use.
Quick-Release Bracket Mounting Kit
The Quick-Release Bracket Mounting Kit allows you to operate the
5000 inside a wheelhouse or cabin by attaching the NAV 5000 to
external antenna. The kit includes:
battery
NAV
an
Unit Holder
o
GPS Antenna Coupler
o
o
U-Bracket, with mounting hardware
o
Exterior Antenna with 50 feet of cable
o
DC/Antenna Interface Box
o
Installation Instructions
The components of this kit are also available separately.
1-8
CHAPTER 2
Getting Ready to Use the NAV 5000
Before your NAV 5000 is ready for use, there are several setup tasks
that must be completed. This chapter describes these tasks in the
order in which they should be performed.
BATTERIES
The NAV 5000 requires six (6) AA alkaline batteries for operation. The
batteries are used to operate the unit without an external power
source. (See Battery Saver on page 5-12.)
Magellan Systems Corporation recommends Eveready Energizer
batteries.
We do not recommend that you operate the NAV 5000 with nickel
cadmium (NiCad) batteries. NiCads have a much shorter life than
alkaline batteries; in the NAV 5000, they last only about 3.5 hours.
Also, the power drop at the end of NiCad battery life is so rapid that
there may be no warning before the unit's memory is lost. Use NiCad
batteries at your own risk.
The NAV 5000 is shipped with alkaline batteries already installed.
Loading the Alkaline Batteries
The unit must be operated with six (6) AA alkaline batteries. Use the
procedure below to load batteries.
Put the batteries in the extra battery clip. Be sure the batteries
1.
are oriented as shown on the clip.
2 Be sure the unit is off.
If the unit was being operated on external power, also discon-
3.
nect the NAV 5000 from the external power source.
TM
2-1
Holding the unit as shown in the illustration below, pull the
4.
battery cover firmly towards the bottom of the unit until it
stops, then lift the door off. To create a seal against moisture,
the cover fits snugly, and will not move easily.
Remove the old battery clip. Insert the new clip in the battery
5.
compartment; it will fit only with the open side facing you and
the clip's external contacts on the right.
OPENING THE BATTERY COVER
Remove any dirt, sand, or other foreign matter from the battery
6.
compartment seal.
Replace the battery cover. Position the cover over the battery
7.
clip and push up firmly until the door settles into place. Be sure
the door is secure.
2-2
Battery Operation
When operated from battery power, the unit operates continuously
once POS, NAV, or VEL has been pressed, updating the position fix
every second. The unit remains on until it is turned off with the ON/
OFF button or the batteries wear out. Continuous Operation is a very
heavy drain on the batteries; you can expect about 10 hours' use from
alkaline batteries in continuous operation.
The unit has a Battery Saver feature, which allows you to reduce the
drain on the batteries. When the Battery Saver is on and POS is
pressed, the unit takes position fixes for two minutes. lf no other keys
are pressed, the unit then shuts itself off.
Refer to page 5-12 to turn the Battery Saver on.
Battery Warning
There are two battery
warnings. The first is a
symbol that appears when
the batteries are low
symbol remains on all
displays until the batteries
are replaced.
. This
If the Battery Saver is off, when the first battery warning appears, the
unit is able to operate continuously for up to 30 minutes. lf the Battery
Saver is on, you can turn the unit on and obtain position fixes 15 more
ti
mes.
The second warning is
added when the batteries
become dangerously low.
lf the batteries are not
replaced, information
stored in the unit's memory
may be lost.
EXTERNAL POWER OPERATION
The NAV 5000 can be operated from an external AC or DC power
supply. When being run on external power, the unit operates continuously until the unit is turned off (with the ON/OFF button) or external
power is lost.
2-3
lt should be noted that when the unit is being operated from external
power, the batteries are
batteries recharged in the unit.
Use only Magellan equipment to connect the unit to an external power
source. All Magellan adapters and interfaces have been designed to
supply the unit with the correct level of DC voltage; the use of any
other equipment may harm the unit and void the warranty.
bypassed.
At no time are alkaline or NiCad
Power Adapters
The unit is connected to an external power source with one of several
Magellan adapters. Discuss your needs with your Magellan dealer to
be sure you purchase the correct adapter.
Currently, AC adapters are available for 110 volts, 220 volts, and 240
volts. There is also a regulated 12-volt DC adapter.
ConnectIng to an External Power Source
Refer to the drawing below to connect the unit to an external power
source.
POWER CONNECTIONS FOR THE NAV 5000
2-4
The external power jack is located on the right side of the unit,
opposite the antenna. Insert the five-pin connector of the adapter into
the power jack.
This message appears
when the level of external
power being supplied to
the unit is below minimum
requirements. The unit is
operating on battery
power.
INITIALIZATION
The NAV 5000 responds more quickly when used within 300 miles
(482.7 km) of its initialized position or last fix.
To initialize, you must know your location (latitude and longitude) within
300 miles (482.7 km). You should also know your altitude as accurately as possible. (Note that normal tidal fluctuations do not affect this
measurement.) lt you do not know your position, call your local marine
electronics dealer, or consult an atlas or chart.
Although you can obtain a position fix without entering an initial position, the unit obtains the first position fix more quickly if a correct initial
position was entered. lt is also possible to operate without having
entered an altitude, but this will affect the accuracy of the position
fixes, especially in 2D operation. Therefore, regardless of which mode
you plan to use, an altitude should be entered. When a 2D position fix
is obtained, the value entered will be used as the default altitude, and
will allow the unit to obtain more accurate fixes. If you will be using the
Automatic Mode, an altitude should be entered for the initial position
because the unit may use either 3D or 2D to obtain fixes.
If no altitude is entered, the unit assumes that altitude is 0.
2-5
lt is also possible to initialize by using the Sky Search (AUX 5) function
to establish your position automatically. This method takes about 15
minutes. lt should be noted that the unit gets the first position fix more
quickly when an initial position is entered manually. (See page 5-8.)
Press the SETUP key. If a
position is already entered,
press the CLEAR key to
erase it.
2-6
Enter your approximate
position within 300 miles
(latitude and longitude).
For example, to enter a
latitude of 34°00.00N, key
in 3, 4, and ENTER.
zeroes are
automatically. (lf
prefer, enter all zeroes
manually.) Use the RIGHT
ARROW to toggle between
entered
Trailing
you
N and S, if necessary.
Press ENTER.
Enter the longitude by
pressing the numbers on
the keypad. Use the
RIGHT ARROW to toggle
between E and W. Press
ENTER.
From the initial position
screen, press the DOWN
ARROW to go to the
mode/altitude display.
Press the RIGHT ARROW
to choose 2D, 3D, or
AUTO Modes.
Remember that in 2D the unit calculates latitude and longitude only,
and altitude is a user-entered value. In 2D, the unit is able to calculate
more accurate position fixes when an altitude is entered at the mode/
altitude display than is possible without a user-entered altitude. (Operation in the 2D Mode is recommended for marine use.) In 3D,
altitude is calculated by the unit. In the Automatic Mode, the unit uses
3D when 4 satellites are visible and 2D when only 3 satellites are
visible.
2-7
Press CLEAR to erase the
old altitude. Key in the new
altitude. (Use the RIGHT
ARROW to toggle between
positive and negative
values.) Press ENTER to
store the altitude.
lf you will be using the unit
in 3D, press the RIGHT
ARROW to change to 3D.
Note that an altitude is also
displayed here. If you want
to, you can change it as
described above.
If you will be using the unit
in the Automatic Mode,
press the RIGHT ARROW
change to AUTO. Press
CLEAR to enter a new
altitude as described
above.
to
Press any function key to exit SETUP.
2-8
ORIENTING THE ANTENNA
In order to obtain a position fix or collect an Almanac, the unit must be
held or placed in direct view of the satellites overhead. Hold the unit
upright or rotate the antenna up as shown in the figure below.
GIVE THE ANTENNA A DIRECT VIEW OF SATELLITES
The unit will not receive signals if its view of the satellites is blocked by
objects or people, or if you attempt to use it inside without an external
antenna.
2-9
OBSTRUCTIONS BLOCK THE SIGNALS
For
ease and comfort of operation, a holder is available for the unit,
which can be mounted to the boat.
COLLECTING AN ALMANAC
The Almanac is a schedule of satellite availability stored in the NAV
5000's memory. This means that before you obtain a position fix, the
unit already knows which satellites are scheduled to be in view (given
your last position or initialized position) and where in the sky to look for
them.
Almanac information is maintained by all satellites, and is updated as
required by GPS system operators to reflect current conditions. Alma
nac information can be collected from any satellite. The NAV 5000
refreshes its Almanac each time POS, NAV, or VEL is pressed.
Therefore, when the unit is in frequent use, it maintains a current
Almanac.
When the unit has not been used recently (generally, nine months or
more), its Almanac may be out of date. The unit can still obtain a
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position fix, however. When POS is pressed the unit will locate a
satellite and update its Almanac before calculating a fix. The unit also
collects an Almanac when POS is pressed and it does not have an
Almanac. (See page 4-10).
lf you need to collect a new Almanac, be aware that it takes about
12-1/2 minutes to collect a complete Almanac once a satellite signal
has been located. (Be sure you have a clear view of the sky.) Since the
receiver is on while the Almanac is being collected, this can be a heavy
drain on your batteries. You might want to connect the unit to extemal
power to collect an Almanac.
lf the unit has lost its memory, it must be reinitialized and a new
Almanac collected. There are several ways to do this. One is to
initialize the unit as described on page 2-5 and collect an Almanac with
AUX 5 (see page 5-8).
You can also press POS. The unit will locate a satellite, collect an
Almanac, and calculate a position fix.
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Press POS. The unit tries
to determine which satellite
is scheduled to be overhead.
Since there is no Almanac
or initial position, the unit
enters Sky Search. The
receiver searches for
satellites in a prescribed
pattern until one is located.
The ALM COLLECT
message appears on the
display when a satellite
has been located and
acquired, and the unit is
collecting an Almanac.
When the unit has located
and acquired three satellites, it calculates a 2D
position fix. Altitude is
assumed to be 0; the fix
may therefore not be
accurate unless you are at
sea level.
The unit then checks the
Almanac to be sure that it
is both complete and
accurate do not turn the
unit off, and maintain a
clear view of the sky until
this message disappears.
Since all non-default SETUP parameters were lost when memory was
lost, you must reenter them. Be sure to reenter your altitude or antenna
altitude also.
You can also reinitialize the unit and collect an Almanac by pressing
AUX 5. The unit will locate a satellite, collect an Almanac, and calculate an initial position.
Press AUX, 5, and ENTER.
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