Welcome to the ultimate and highly advanced navigation, the Global Positioning System.
Although GPS is far superior to other navigational systems and will operate under any weather
conditions, please be advised that no single device should ever be solely relied on for
navigating.
Your GPS unit is only a navigational aid and does not replace the need for careful position
charting and good judgment.
Now let's find out what GPS is all about.
The concept of a highly accurate worldwide navigation and positioning system that could
be used continuously at any time of the day began with the U.S. government.
It envisioned radio signals transmitted from a satellite constellation, a system that would
not be fraught with the limitations of existing navigation technologies.
Their vision was realized with a global positioning system made possible by rapid advancements
in aerospace technology, a firm financial commitment from the U.S. government, and the
intense participation of individuals and corporations with communications expertise.
The heart of the global positioning system is a constellation which will eventually consist
of 21 satellites and three spares.
Circling the earth twice daily, each satellite is in a fixed orbit approximately 10,900 nautical
miles above the surface of the earth, inclined at 55 degrees from the equator.
The new navigation infrastructure is available to a variety of worldwide users, including
recreational boaters, fishing and shipping fleets, general and commercial aviation aircraft,
and military forces.
Recent technological innovations have made GPS worldwide navigation an affordable reality
for everyone.
Information provided is precise and transmitted in real time.
The most accurate on-demand worldwide navigation system, GPS is extremely resistant to interference
from weather, earth-based radio signals, and electronic equipment.
All of these advantages make GPS superior to any other navigation system.
Here's how it works.
Each GPS satellite continuously transmits two types of orbit data used to calculate
a position, almanac and ephemeris.
Listening only to one satellite, a GPS receiver can gather the almanac information which contains
the approximate location of every satellite in the system.
From the almanac, the receiver determines which satellites will give the best geometries.
The better the geometry, the more accurate the position fix.
The ephemeris data is more precise and is used in obtaining the actual navigation information.
In addition to this information, two codes are transmitted, a protected code, P code,
and an unprotected code, CA code.
The P code is reserved for military use.
The CA code is intended for public access.
The CA code has two purposes.
It provides immunity of the signal to interference from undesired signals.
Secondly, the CA code is used in determining precise range of the user from each satellite,
the first stage in calculating a position fix.
While the global positioning system may appear complex, navigation with GPS can be amazingly
simple.
A well-designed GPS receiver uses the signal information in a fundamental geometric equation.
It solves the equation and presents it in easy to use navigation displays.
To obtain a position fix, a minimum of three satellites are read.
First, the receiver determines the time of transmission and reception of the signal from
each satellite.
It then multiplies the difference in these times by the speed of light, 186,000 miles
per second, to arrive at an estimate of the satellite's distance from the receiver.
Using the calculated distance and the calculated orbital position of each satellite, the receiver
determines and displays a position fix in degrees of latitude and longitude.
The exact time of that fix, accurate to one ten millionth of a second, can also be determined.
A master control station on Earth serves to gather pertinent navigation data from the
satellite constellation.
Monitor stations and ground antennas strategically located around the world passively track the
GPS satellites, relaying data to the master control station.
If for any reason a satellite emits erroneous data or is otherwise not operating properly,
a ground station will mark it unhealthy, and the satellite will broadcast this fact to
the user.
Receivers are programmed to ignore the unhealthy ones, reading instead the next best satellite
for determining the user's position.
The most remarkable feature of the Global Positioning System is its accuracy.
Position accuracies of 30 meters or better are commonly obtained from GPS receivers.
Repeatable accuracy, that is being able to return to the same spot, will also be experienced
by GPS users.
The completed GPS constellation of 21 satellites will provide 24-hour continuous coverage worldwide.
Unlike all other electronic navigation systems, the signal never weakens because of the distance
from the broadcast source.
Another remarkable feature of GPS is its resistance to interference from conditions which disturb
other electronic systems.
Thunder, lightning, heavy weather, radio signals, onboard electronics, passing ships, onshore
electronic installations, ignition of boat engines, portable radio receivers and so forth.
Most of the current means of electronic navigation are land-based like Omega, DACA, radio direction
finders and Loran-C. These systems have inherent limitations in coverage areas, accuracy and
susceptibility to interference. Transit, Sat-Nav, the only other satellite-based system, does
not provide continuous navigation information, only periodic position fixes once every one
to three hours.
In addition, the user must already have a close approximation of his position and velocity
to make use of the system. Sat-Nav requires about 15 minutes, even under good conditions,
to make a fix. Omega, Loran-C and Transit are all destined to be replaced by GPS.
Prior to demonstrating how to operate your particular GPS unit, let's just review some
extremely important precautions that should be taken.
The Global Positioning System 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 inaccurate,
such as changes in the position or health of a satellite. Accuracy can also be affected
by poor geometry with respect to the satellites. If an accuracy warning appears on the screen,
do not use the data.
At this time, 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 modification to your unit.
One of the most important things you must know is whether your unit is set for two-dimension,
2D, or three-dimension, 3D mode of operation, if this setting is not fixed on your unit.
Using only three satellites for obtaining a position, 2D mode gives a latitude and longitude
position. However, 2D requires that you enter a correct antenna altitude within 15 feet
or your altitude above sea level plus the height of the antenna. If you enter the wrong
antenna altitude, your position fix will be inaccurate. The unit should be initialized
within 300 miles of its true location. In 2D mode, if you fail to do this, your position
fixes could be wrong.
Well, enough on what GPS is and how it works. Let's get right down to how you actually
operate your equipment.
Congratulations on choosing a fine GPS navigator by Garmin. Whether you choose the GPS 75 or
model 65, you should find this video to be full of assistance in helping you to understand
and apply the instructions provided by the manufacturer in your owner's manual.
Please be advised that this video should not be used in any way during actual navigation.
The program owners, producers, and distributors assume no responsibility for any consequential
losses of any nature with respect to this video.
After you turn your GPS on, it will conduct a series of self-tests and display this notice.
Following completion of the tests, the satellite bar graph page will be displayed and the GPS
will begin acquiring satellites. After a position is found and if no keys have been pressed,
the position page will be displayed and the unit is ready for normal operation.
If four or more satellites with good geometry are available, the GPS will automatically
operate in the 3D mode in which latitude, longitude, and altitude are computed.
If only three satellites are available, the unit will operate in 2D mode in which only
latitude and longitude are computed. When operating in the 2D mode, the unit will use
the last computed altitude or your last entered altitude.
Your GPS will automatically update satellite orbital data as it operates. If you have not
operated your unit for a period of six months or longer, it will take approximately 15 minutes
to search the sky and collect new orbital data. You'll be informed when your unit is
searching the sky with the message searching the sky. Once satellite orbital data is collected,
it will be stored in memory. The memory is maintained by an internal battery. Therefore,
the data will not be lost when you turn your GPS off.
There are four status pages available by pressing Power Stat. Three pages display satellite
tracking status and the fourth is a menu of auxiliary functions. The satellite bar graph
shows the signal quality of each visible satellite graphically. The receiver status is also shown
at the top of the screen. The satellite numbers 1 through 32 are represented along the bottom
of the graph. Signal quality is represented along the side with one weakest to nine strongest.
If a satellite is visible but not tracked, the signal quality will be blank. The satellite
status page shows the ID, azimuth, elevation, and signal quality of each satellite in a
table format. The receiver status again is displayed at the top of the screen as well
as the dilution of precision, DOP, and the estimated position error, EPE. The satellite
sky view page shows the azimuth and elevation of each visible satellite in a graphic sky
view format. Additionally, the DOP and EPE are displayed. The azimuth and elevation are
useful in determining whether a satellite signal is blocked by buildings, mountains,
or other obstructions. If a satellite is not currently being tracked, it will be displayed
in reverse video on the screen. The auxiliary menu page enables the selection of various
setup and utility functions by moving the cursor to an item with the arrow keys and
pressing enter. The utility page is described later. As mentioned earlier, the position
page is automatically displayed once a position is obtained. This page displays track, ground,
speed, latitude and longitude relative to the selected map datum, as well as a choice
of altitude above mean sea level, MSL, or time, cyclic field. When the GPS is performing
2D navigation, the last known altitude will be used in the latitude longitude computation.
If the altitude is not accurate within a few hundred feet, you should manually enter your
altitude. To enter the altitude, 2D only, use an arrow key to move the cursor under
the altitude. Enter the altitude. If your antenna is mounted on a high mast, make sure
that you add the mast height. Remember to complete the data entry by pressing enter.
During initial satellite acquisition, the displayed position is the last computed position
stored in the GPS. If your position has moved several hundred miles or more with the power
off, the unit may go into the auto locate mode. This process can take up to 10 minutes.
Alternatively, you may enter a more accurate initial position to speed up the acquisition
process. To enter the latitude longitude, use the arrow key to place the cursor on the
latitude hemispheric designation at the far left. Check the hemispheric designation, north
or south, of the latitude. If it is correct, go to the next step. If it is incorrect, press
clear until the correct hemispheric designation is displayed.
Place the cursor on the latitude field and enter the latitude. Depending on the position
format selected, you'll enter the latitude in one field, degrees only, two fields, degrees
minutes, or three fields, degrees minutes and seconds, or UTM. You must press enter
for each field to confirm the data entry. Check the hemispheric designation east or
west of the longitude in the same manner for latitude. Enter the longitude. Remember to
complete the data entry by pressing enter. The GPS allows you to create, store, and use
250 alphanumeric waypoints. A waypoint consists of a name up to six letters and or numbers,
its latitude longitude location, last time date of modification, and a two-line comment.
There are four waypoint pages. The soft keys at the bottom of each page allow the selection
of each page. That's waypoint definition, nearest waypoints, proximity waypoints, and
waypoint list. To start the waypoint pages, press waypoint. The waypoint definition page
allows you to review, create, and modify waypoints. The cyclic field allows you to display one
of the following. One, the date and time the waypoint location was last modified. Two,
a two-line comment of the waypoint. Each line is a separate field of 20 characters. Or three,
range and bearing from a reference waypoint. To create and modify or review a waypoint,
move the cursor to the waypoint name field. Then enter the desired waypoint name. To create
or modify position, enter the waypoint latitude and longitude. Note that if a waypoint is
being used for navigation, its position cannot be modified. An attempt to modify the position
of such a waypoint will result in the message, can't change active waypoint. The waypoint
list page allows viewing of the stored waypoints in the unit. The list may be scrolled with
the arrow keys to view all the waypoints. From this page, waypoints may be selected
for deletion, renaming, or to activate a direct go to. To delete a waypoint with the arrow
keys, place the cursor on the desired waypoint. Press clear and enter. The confirmation page
is displayed. Press enter to confirm or clear to cancel. Note that if you attempt to delete
a proximity or route waypoint, a message will be displayed. You must delete the proximity
alarm or the route before you can delete the waypoint. To rename a waypoint with the arrow
keys, place the cursor on the desired waypoint. Type in a new name for the waypoint and press
enter. The confirmation page is displayed. Press enter to confirm the name change or
clear to cancel. The auto store function allows you to capture your position at the touch
of a button for future reference. This function saves your current position in a waypoint.
Additionally, you may record your navigation path by inserting the captured waypoints into
a route. We will explain this later. The auto store page displays the waypoint name, captured
position and optional storage route. An auto store waypoint name is pre-assigned as a three
digit number. You may change this to any name you desire. Auto store waypoints may be used
for any waypoint operation and will be part of the 250 available waypoints. Press auto
store. The pre-assigned waypoint name is on line one. Note that the auto store location
is captured as soon as you press auto store. This allows you all the time you need to change
the waypoint name and or confirm the auto store. If you wish to give the waypoint a
different name, move the cursor to the waypoint name field and enter the name of your choice.
If you enter a waypoint name already used, you will be informed with the message waypoint
exists. Enter a different name if this occurs. Press enter. The go to function allows you
to quickly set a course from your position to any waypoint. To activate the go to function,
press go to. This page will be displayed with the cursor on the go to waypoint field. If
the GPS is currently navigating to a waypoint, that waypoint will be offered as the default
go to waypoint. If the waypoint field is blank or the waypoint shown is not the desired destination,
type the new name right over the old name. Note that if a non-existent waypoint name
is entered, an error tone will sound. Confirm the default go to waypoint by pressing the
enter key. The nav page will be displayed. Alternatively, the go to function may be quickly
activated from many pages. The nearest waypoint page or the waypoint list by placing the cursor
over the desired waypoint name and pressing the go to key. The go to page will be displayed
with the cursor on the go to waypoint name. The go to function will be activated when
the enter key is pressed. To cancel the go to function, press go to. Press clear. The
go to waypoint name will become blank. Press enter. The GPS will start to navigate using
the active route if it has been programmed. Otherwise, the GPS will stop computing waypoint
navigation data. There are four navigation pages available from the nav key. You may
cycle through the following with soft keys at the bottom of each page. Navigation summary,
graphic course deviation indicator, graphic plotter, and present position page. The navigation
summary page displays direction, distance, and speed information to direct you along
a route or a go to destination. The active leg or route waypoints or go to waypoint is
shown at the top of the screen. The CDI is at the bottom of the page. Current CDI scale
setting is shown at each end of the scale. This is replaced by the cross track distance
if the D bar goes off the scale. A relative bearing pointer at the center of the CDI indicates
the bearing to the waypoint relative to the current track. Notice that this page has four
cyclic fields available. The field options are as follows. Field number one provides
a choice of A, bearing to destination waypoint, B, course to steer, C, desired track, D, ground
track, or E, turn. Field two provides a choice of A, range to destination waypoint, B, cross
track error, C, along track distance, or D, distance made good, back to the starting point.
Field number three provides a choice of A, ground track, B, course made good, or C, ground
speed. Field number four provides a choice of A, ground speed, B, estimated time on route,
C, estimated time of arrival, or D, velocity made good. The CDI page shows a graphic highway
display. The active waypoint is shown at the top of the screen. Navigation values for track,
ground speed, bearing, range, and estimated time on route are shown. The center line of
the highway represents the desired track. The outer lines give a perspective view of
the distance to a waypoint. As the waypoint comes into range, it will be displayed, and
the outer lines will become parallel. The plot page shows a graphic top view of your
course. The destination waypoint is shown at the top right of the screen. Your present
position is shown as a plus. This is in the middle of the page. The track history and
or the active route are shown as a solid line. Nearby waypoints are displayed as diamonds.
You may view the waypoint name by scrolling to the point with the arrow keys. A go to
may be performed by pressing go to while the cursor is on the waypoint. The scale distance
for the screen, the distance represented by the height of the screen is at the lower left
of the screen. The scale number directly above the scale distance may be changed by moving
the cursor to the scale number and pressing clear, or by entering a new number, zero through
nine. Finally, the plot page can be oriented as a north up, ground track up, or desired
track up display. The man overboard function allows you to set an instantaneous course
to a captured position, providing rapid response to an emergency situation. To activate the
man overboard function, press MOB twice. This page will be displayed, and the present position
will be captured in a waypoint named MOB. Press enter to navigate to the man overboard
waypoint. A navigation page will be displayed. Select the desired page with the soft keys.
The GPS offers a route navigation feature for you to navigate along a predefined sequence
of waypoints. The GPS route capability allows you to create and store ten routes numbered
zero through nine, containing up to twenty waypoints each. Routes one to nine, the storage
routes can be activated to travel either in the order you define the waypoints, or in
reverse order. Route zero, the active route, is the route you are navigating. The waypoint
towards which you are navigating is called the active to waypoint. The waypoint immediately
behind you is called the active from waypoint. The line that connects the active from and
the active to waypoints is called the active leg. The GPS features automatic leg selection,
which will select the route segment closest to your position as the active leg. The GPS
also features automatic leg sequencing. As you pass a waypoint in the route, the unit
will automatically select the next waypoint as the active to waypoint. There are three
route pages in the GPS. The soft keys at the bottom of each page allow cycling through
each page. The route definition page allows you to create, change, review, copy, and activate
routes. Remember that route zero is always the active route. If you create a route in
route zero, you should copy it into an empty storage route one through nine. When you activate
a storage route one through nine, it will be copied to route zero for activation. Press
the route key. If you are not already on the route definition page, press the route soft
key. On the route number field, you may choose between routes zero through nine with clear.
Next to this is another cyclic field, which allows you to activate the route, clear the
route, copy the route to another location, or invert the order of the waypoints in a
route and activate it. The arrow keys allow you to scroll through the list of waypoints
in a route. To create a route, move the cursor to the route number field and press clear
until you find an empty route. Scroll to the first blank waypoint name field and type in
a waypoint if you wish to put in the route. Press enter. Repeat this process for each
waypoint you want to add up to a total of twenty. To copy a route, select the route
definition page. Highlight the route number field and select the route number to copy
from with clear. Highlight the route action field with the arrow keys and press clear
until copy two is displayed. A third field now appears in the top right corner. Highlight
this field and select the destination route number with clear. Press enter. The route
is now copied. Routes are activated on the route definition page also. You may activate
any route in the displayed order or in reverse order. Remember when a new route is activated
the previous contents of route zero will be overwritten. If you wish to save route zero
be sure to copy it to an empty route first. To activate a route, select the route definition
page. Highlight the route number field and select the route number to activate with clear.
Select the route action field and with clear select activate. Press enter to activate the
route. To invert a route follow the same steps for activating a route, but select invert
at the route action field. Press enter to activate the route in an inverted order. To
edit an existing route select the route definition page. Highlight the route number field and
select the route you wish to edit. To insert a waypoint into the route highlight the waypoint
you want to place the new waypoint in front of. Type in the new waypoint name. Press enter.
The new waypoint is added to the route. To delete a waypoint from the route highlight
the waypoint you wish to delete. Press clear and enter. If you attempt to add a waypoint
to a route that already contains 20 waypoints you will be informed with a message route
is full. You may delete an unwanted route from the route definition page. To delete
a route highlight the route number field and select the route you wish to delete with clear.
Select the route action field and select clear with the clear key. Press enter to delete
the route. The active route page displays the waypoints of the active route starting
with the active from and active to waypoints on the top line. Press the active soft key
to select this page. The waypoint list displays route waypoints starting with the active to
waypoint. For each waypoint additional information is available. The first column displays range.
The second column is a cyclic field that displays estimated time on route in hours minutes or
minutes seconds as appropriate. Estimated time of arrival or desired track. You may scroll
through the waypoint list with the arrow keys. To edit the active route to insert a waypoint
highlight the waypoint you wish to place the new waypoint in front of. Type in the new
waypoint name press enter. The new waypoint is added to the route. To delete a waypoint
highlight the waypoint you wish to delete press clear and enter. The route list page
displays a list of all routes currently stored in memory. Press the list soft key to select
this page. The route list page displays the route numbers beginning waypoints and final
destination waypoint. You may also activate or delete a route from the route list page.
To activate a route highlight the route you wish to activate with the arrow keys press
enter. The route definition page is displayed with the active action highlighted. Press
enter to activate the route. To delete a route highlight the route you wish to delete with
the arrow keys press clear. The route definition page is displayed with the clear action highlighted.
Press enter to delete the route. The GPS auto store feature is the quickest and easiest
way to build a route as you go. With auto store each time you turn on a new track, pass
a significant landmark or reach some location of interest you can save the location and
create a route at the same time. Each auto store waypoint can be added to the same route
as you are traveling. With the unit operating in 2D or 3D navigation mode press the auto
store key to save your starting location. At this point you may change the auto store
name if you wish. Select an empty route to store the waypoint by highlighting the append
to route field and pressing clear until the desired route number is displayed. Press enter
to add the waypoint to the selected route. Repeat these steps each time you arrive at
a location you wish to add to the route, up to a total of 20 waypoints per route. An important
feature of the GPS is the ability to display up to 9 nearest waypoints within 100 nautical
miles of your present position. In an emergency you may use the nearest waypoint feature to
find the closest point of safety in your area. If the nearest waypoint page is not currently
displayed press the nearest soft key NRST. This page displays the waypoint names including
bearing and range from present position. You can scroll through the waypoints listed by
using the arrow keys. To go to a nearest waypoint move the cursor to the desired waypoint name
with the arrow keys. Press go to and enter. The proximity waypoint page allows you to
define an alarm circle around a waypoint. This feature is useful in defining an area
around a rock reef or restricted waters. When you approach one of these waypoints the GPS
will notify you with an alarm tone and the message prox alarm if you enter the alarm
circle. The GPS allows you to define a maximum of 9 proximity waypoints. Scroll through the
proximity waypoint list using the arrow keys. To set a proximity waypoint select the proximity
waypoint page with the prox soft key. Select a blank waypoint name field with the arrow
keys. Enter the waypoint name. Note that if neither the waypoint name nor the location
exists in memory the waypoint definition page will be displayed. You must then enter the
waypoint location. Press enter. Enter the proximity alarm distance. Press enter to enable
the proximity alarm. If the newly created proximity alarm circle overlaps with an existing
proximity alarm circle you will be informed of the overlap with the message proximity
overlap. As long as the overlap remains this message will be displayed each time the GPS
is turned on. If you enter the overlap area the unit will only inform you of the nearest
waypoint. Another way to create a waypoint is by referencing an existing waypoint. By
indicating the bearing and range from a reference waypoint the GPS is able to compute a latitude
and longitude location for the new waypoint. To create a waypoint by referencing another
select the waypoint definition page with the waypoint soft key. Highlight the waypoint
name field and enter the new waypoint name. Press enter. Highlight the ref field and enter
the existing waypoint that will be used as reference. If the reference field is not currently
shown highlight that cyclic field and press clear until it's displayed. Press enter. Enter
the bearing and distance from the existing waypoint to the new waypoint. Press enter.
A latitude and longitude location for the new waypoint should now be displayed. Throughout
this video each time we've encountered the waypoint name field we have entered the waypoint
name with the alphanumeric keys. An alternative is to use the waypoint scanning feature. As
an example use the go to waypoint field. Press go to. The waypoint name field is highlighted
and may be blank or may already show a go to destination. If the waypoint name field
is not blank press clear. Press waypoint. A waypoint name is now displayed. Scan for
the desired waypoint with the arrow keys. As you're scanning up to nine nearest waypoints
will be shown first. This will be followed by the entire list in numeric and alphabetical
order. To limit the scanning range you may specify the first letter or number of the
waypoint name. To perform a limited scan select the waypoint definition page with waypoint
and the waypoint soft key if needed. Highlight the waypoint name field with the arrow keys.
If this field is not blank press clear. Enter the first character of the waypoint name.
For this example enter the letter G. Press waypoint. Use the arrow keys to scan through
all waypoints that begin with the letter G. The GPS auxiliary pages allow you to do utility
and set up functions to customize your unit. The 11 auxiliary pages are accessible from
the auxiliary menu by highlighting the page you want and pressing enter. The soft keys
allow changing to previous and next pages. The auxiliary soft key takes you back to the
auxiliary menu page. From this page you may change between various operating modes by
highlighting the operating mode field and pressing clear. You may select simulator mode,
normal mode or battery saver mode. Also from this page the position and velocity filters
may be changed. Changing the filter settings will alter the GPS response time to changes
in track or ground speed. To change the filter settings highlight the appropriate field and
cycle through the filter settings automatic, fast, medium and slow with clear. The fast
setting will provide instantaneous response, three seconds maximum response time to changing
conditions. The medium approximately 20 seconds or slow approximately 120 seconds may be more
desirable for slow speed operation where frequent ground track changes will occur. It is highly
recommended that you select the automatic setting for most applications. The plotting
setup page is used to configure the plot page and select the types of information that will
be displayed. The first cyclic field defines the orientation of the plot map. The top of
the plot map may be north or north up the direction of your current ground track, track
up or the direction of the active leg of a route, DTK up. To select the desired option
highlight this field and press clear. Your present position and nearby waypoints are
displayed on the plot map at all times. The second cyclic field determines what additional
information will be displayed on the plot map. You may display the active route and
a stored ground track showing where you have been, only the active route or only the ground
track or neither. The ground track is stored at a frequency that you can define either
by time interval, resolution or distance. Select the desired frequency unit by highlighting
this field and pressing clear. To store the ground track at selected time intervals highlight
the storage frequency field, the third line and select interval with clear. Press enter.
Enter the time interval between stored positions starting with hours, then minutes, then seconds.
Press enter after entering data in each numeric field. To store the ground track by distance
highlight the storage frequency field and select distance with clear. Press enter. Enter
the distance and press enter. When your position moves this distance in any direction a new
position will be added to the stored ground track. Note that distance storage may be preferable
to resolution storage if the ground track will include a large number of turns. If the
planned course will be primarily straight line travel you should select resolution storage.
In this application considerably less memory is used for the same distance traveled. To
store the ground track by resolution highlight the storage frequency field and select resolution
with clear. Press enter. Enter the resolution range and press enter. When your position
moves this defined range off a projected course line a new position is added to the stored
ground track. The track storing function may be turned on and off by highlighting the track
field and pressing clear. From this same field the track may be set to wrap around through
available memory deleting the oldest track information and using the memory to store
the new track position. The amount of memory used at any given moment is shown on the bottom
line. When available memory is filled or the track is no longer needed it may be cleared
by highlighting clear and pressing enter. The units heading page is used to select the
units to display for position distance speed and heading information. Select the desired
position units by highlighting the position field and pressing clear. You may choose between
degrees only degrees and minutes degrees minutes and seconds or UTM coordinates. Select the
desired distance and speed units by highlighting the nav field and pressing clear. You may
choose between nautical nautical miles knots feet statute miles miles per hour feet or
metric kilometers kilometers per hour meters units. Heading information can be displayed
referencing magnetic north automatically calculated or user defined or referencing true north.
Select the desired heading reference by highlighting the HDG field and pressing clear. When the
auto mag variation option is selected heading information will reference the automatically
calculated magnetic variation shown. For most applications the auto mag feature will provide
accurate heading information. If the auto magnetic variation is not correct you may
define the magnetic variation by selecting user mag var. If the user mag var option is
selected the magnetic variation is then entered. To enter a user defined magnetic variation
highlight the HDG field and select user mag var with clear press enter. The variation
direction is highlighted to change the direction press clear press enter. Enter the variation
degrees and press enter. From the alarms CDI page you may define three alarms and turn
them on or off and configure the graphic CDI to your preference. The alarms are available
for anchor drift arrival at a destination waypoint and an alarm clock. To set the anchor
alarm highlight the anchor alarm distance and enter the maximum allowable drift. Setting
the anchor alarm to its smallest value.01 unit may result in a false alarm. Please note
that under certain circumstances below average satellite geometry degraded reception etc.
the position error of the GPS may be greater than the lowest scale settings available for
this alarm. Press enter. The on off cyclic field is highlighted. If the alarm is not
turned on press clear. To set the arrival alarm highlight the arrival alarm distance
and enter the distance from a destination at which you want the alarm to sound. Press
enter. The on off cyclic field is highlighted. If the alarm is not turned on press clear.
To set the alarm clock highlight the alarm clock time and enter the desired alarm time.
Note that the alarm time may be either UTC or local time depending on the setting on
the date time page. Press enter. The on and off cyclic field is highlighted. If the alarm
is not turned on press clear. The graphic CDI may be configured to the desired scale
and steering orientation. Scale settings of plus or minus 10, 50, 1.00, 5.00, 10.0 or
50.0 units are available. The scale settings represent the distance from the center of
the CDI to either end. You may change the scale setting by highlighting the CDI scale
field and pressing clear. The CDI steer 2 orientation determines how you interpret the
D bar when it moves. You may select steer 2 center or steer 2 D bar by highlighting
that field and pressing clear. A steer 2 center orientation in effect displays your position
as the D bar and the center of CDI is the desired track. Thus when you're off course
you would steer towards the center of the scale. A steer 2 D bar orientation is just
the opposite. The D bar represents the desired track and the center of the scale represents
your position. When you are off course you then steer towards the D bar. The date time
page displays the UTC coordinated universal time or greenage mean time date and time.
The local offset or time difference is shown on the next line. For time zones west at the
UTC zone enter a negative offset. The minus sign is on the nine key. The cyclic field
for display options determines which time UTC or local will be displayed on the other
GPS pages. To change this option highlight this field and press clear. The timer field
can be selected as count up or count down by highlighting and pressing clear. To clear
the count up timer highlight each time field press clear and then enter. To set the countdown
timer enter the hours minutes then seconds to count down from. The timer expired message
will be displayed when the timer reaches zero. From the audio and display page you can turn
the message and or keypad tones on and off. Change the display contrast and change the
time out for the display backlighting. Select the desired tone option by highlighting the
tone field and pressing clear. To change the display contrast highlight change contrast
and press enter. The contrast bar is highlighted. Press the left or right arrow key to change
the contrast level. When the desired contrast level is reached press enter. The backlighting
timeout determines the length of time the display and keypad backlighting will remain
on. If no keys are pressed for the specified time the backlighting will automatically shut
off. Set the timeout interval by highlighting that field. Entering the desired timeout and
pressing enter. From the interface page you may select the output format needed to connect
your GPS to other equipment. Plotter, autopilot, etc. You may select between NEMA 0180, NEMA
0182 and NEMA 0183 data formats by highlighting the cyclic field and pressing clear. A waypoint
and route transfer option is also available. When selected this option allows you to transmit
the GPS waypoint and route memory to a PC compatible computer or to another GPS or you
may select receive and the GPS will receive new waypoint and route information from a
PC compatible computer or another GPS. When the receive option is selected the new information
received may be added to existing memory receive update or it can replace existing memory receive
replace. When the transfer process is completed you must return the transfer option field
to stop before exiting the interface page. Select the desired map datum reference from
the map datum page. You may choose from 101 predefined map datums or you may define your
own. If the map chart you are using specifies a reference datum select that datum on your
GPS. If the map or chart does not specify a reference datum you may select each datum
applicable to your region until you find the datum that provides the best positioning at
a known point. Note that the GPS is shipped from the factory with the WGS84 datum selected.
To change the predefined datum highlight the change field and press enter. With the arrow
keys find the desired datum and highlight it. Press enter. The new datum is selected.
To create a user defined datum highlight the predefined field and press clear. User defined
is now displayed. Press enter. Select a north N or south S correction and press enter. Enter
the correction distance in degrees, degrees minutes or degrees minutes seconds. Press
enter for each numeric field. Repeat the previous two steps. This time define an east or west
correction. The sunrise sunset page allows you to calculate the sunrise and sunset times
for a given waypoint location on a selected date from 1990 through 2089. To calculate
the sunrise sunset times for a waypoint highlight the waypoint name field and enter the desired
waypoint name. Press enter. The date field is highlighted. Enter the day then month then
year to calculate the sunrise sunset times. Press enter on each alphanumeric field. Once
the year is selected and enter is pressed the calculated sunrise and sunset times will
be shown. Please note that the times shown will be either UTC or local depending on the
selection made on the date time page. The trip and fuel planning page allows you to
calculate time and fuel requirements between any two waypoints or for any programmed route.
On the first cyclic field you will choose between waypoints or routes planning by highlighting
and pressing clear. If route planning is selected you would then select the desired route number
and the portion of the route a given leg or all of the route to calculate for. The final
step is to enter speed and fuel flow rates. The GPS will then calculate the desired track,
fuel requirements, range and estimated time on route. To perform a trip and fuel plan
waypoint to waypoint highlight the first cyclic field top left and then press clear to select
waypoints. Highlight the waypoint name field on the second line and enter the first waypoint
name followed by enter. The second waypoint name field is now highlighted. Enter the second
waypoint name followed by enter. The speed field is highlighted. Enter the intended speed
and press enter. The fuel flow field is highlighted. Enter the estimated fuel flow followed by
enter. The GPS will now display the calculated figures. To perform a trip and fuel plan for
a route highlight the first cyclic field top left and select route with clear. Highlight
the next cyclic field and press the desired route number by pressing clear. Highlight
the leg field and select the desired leg or select all for the entire route using clear.
Highlight the speed field and enter the intended speed followed by enter. Highlight the flow
field and enter the estimated fuel flow followed by enter. The GPS will now display the calculated
figures. You may recall that some messages will remain on the message page after being
viewed. When this occurs the MSG annunciator remains on but does not flash in the lower
left corner. To view these messages select messages from the auxiliary page. We hope
you enjoy using your Garmin GPS and on behalf of Bennett Marine Video we wish you many happy
voyages.