Garmin Gps Plus 2 Manual

							75
Screen Contrast
The GPS II
+has adjustable screen contrast controlled by an on-screen bar scale.
To set the screen contrast:
1. Highlight the ÔcontrastÕ field, and press ENTER.
2. Adjust the bar scale to the desired contrast, and press ENTER.
Note: The screen contrast can also be adjusted by pressing the rocker keypad
while on the Satellite Page (see p. 20).
Screen Backlighting
The screen backlight timer is adjustable for 0, 15, 30, 60, 120, and 240 seconds.
The Ô0Õ setting will keep backlighting on continuously. Whenever backlighting is on,
a bulb icon will appear on the Satellite Page.
To set the backlight timer:
1. Highlight the Ôlight timeoutÕ field, and press ENTER (Fig. 75).
2. Select the desired setting, and press ENTER.
3. To turn lighting on and off, press the red power key briefly.
Reference
Fig. 75
Note: Battery life will be sig-
nificantly affected by the
amount of time you have the
backlight on. To ensure the
longest battery life, keep the
screen backlighting at the
default 15-second option.
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							76
Navigation Setup
The navigation setup submenu page (Fig. 76a) is used to select units of measure-
ment for position formats, map datums, CDI scale, units, and heading information.
Position Formats
The default position format for the GPS II
+is latitude and longitude in degrees
and minutes (hddd¼mm.mmmÕ). You may also select degrees, minutes and seconds
(hddd¼mmÕss.sÕÕ); degrees only (hddd.ddddd¼); UTM/UPS coordinates; or British,
German, Irish, Maidenhead, Swedish, Swiss, or Taiwan, or User grid formats.
To select a position format:
1. Highlight the ÔposnÕ field, and press ENTER (Fig. 76b). Select the desired setting, and
press ENTER.
User Grid Option
The user grid option lets you create a user-defined position format by establish-
ing factors such as longitude of origin, scale, and false Easting or Northing.
To define a user grid:
1. Select ÔUser GridÕ, and press ENTER. Enter values for longitude origin, scale, and false
Easting and Northing, and press ENTER. Highlight ÔSAVE?Õ, and press ENTER.
Reference
Fig. 76a
Fig 76b
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							77
Map Datums
The ÔdatumÕ field is located just below the ÔpositionÕ field and comes with a WGS
84 default setting. Although 106 total map datums are available for use (see
Appendix E for map datums), you should only change the datum if you are using
maps or charts that specify a different datum than WGS 84.
To select a map datum:
1. Highlight the ÔdatumÕ field, and press ENTER.
2. Select the desired setting, and press ENTER.
To define a user datum:
1. Highlight the ÔdatumÕ field, and press ENTER.
2. Scroll through the map datum options until ÔUserÕ appears (Fig. 77), and press ENTER.
3. Enter values for ÔDXÕ, ÔDYÕ, ÔDZÕ, ÔDAÕ, and ÔDFÕ using the rocker keypad, and press
ENTER.
4. Highlight ÔSAVE?Õ, and press ENTER. The setup menu will reappear.
Reference
Fig. 77
Warning:The user datum
function is recommended only
for individuals trained in cre-
ating map/chart datums.
Incorrect entries may result in
substantial position errors.
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							78
CDI Scale Settings
The course deviation indicator (CDI) definition field lets you select the +/- range
of the CDI bar scale on the Highway Page. Three scales are available: +/- 0.25
(default), 1.25, and 5.0 miles or kilometers. Note: This CDI value represents the full
deflection of scale to either side.
To enter a CDI scale setting:
1. Highlight the Ôcdi scaleÕ field (Fig. 78a), and press ENTER.
2. Select the desired setting, and press ENTER.
Units of Measure
The GPS II
+lets you select statute (default), nautical, or metric units of measure
for all ÔspeedÕ and ÔdistanceÕ fields.
To change the unit of measure:
1. Highlight the ÔunitsÕ field (Fig. 78b), and press ENTER.
2. Select the desired unit of measure, and press ENTER.
Reference
Fig. 78a
Fig 78b
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							79
Magnetic Heading Reference
The GPS II
+Õs heading information can be displayed referencing magnetic north
(automatic or user-defined), true north, or calculated grid headings. The default set-
ting is automatic magnetic north, which is suitable for most applications.
To select a heading reference:
1. Highlight the ÔheadingÕ field (Fig. 79a), and press ENTER.
2. Select the desired heading preference, and press ENTER.
To enter a user-defined magnetic heading:
. 1. Select ÔUser MagÕ and press ENTER (Fig. 79b).
2. Enter the degrees and direction of magnetic variation, and press ENTER.
Reference
Fig. 79a
Fig. 79b
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							80
Interface Setup
The GPS II
+Õs interface page lets you specify the formats for connecting external
devices. There are six options: GRMN/GRMN, None/None, RTCM/None,
RTCM/NMEA, NMEA/NMEA, and None/NMEA. Each option lists the input format
first, followed by the output format.
To select I/O format:
1. Highlight the I/O field, and press ENTER.
2. Select the desired setting, and press ENTER.
The GRMN/GRMN setting is a proprietary format that lets you exchange infor-
mation such as waypoints, routes, and track logs between two GARMIN GPS units or
a GARMIN GPS and a PC. There are eight data transfer options: send alm, send wpt,
send trk, send rte, request alm, request wpt, request trk, request rte.
To select a transfer option:
1. Highlight ÔHOSTÕ (Fig. 80), and press ENTER.
2. Select a desired setting, and press ENTER.
To disable all interfacing capabilities, select the None/None setting. If you want
to output NMEA data without any differential input capability, select ÔNone/NMEA.Õ
Reference
Fig. 80
During data transfer, the num-
ber of packets being exchanged
will be displayed on screen.
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							Reference
81
DGPS Interface
The last two format settings allow the differential-ready GPS II
+to accept RTCM
DGPS corrections in RTCM 104 version 2.0 format. Using DGPS corrections will
improve receiver accuracy to 1-5 meters, regardless of errors induced by the govern-
mentÕs Selective Availability (SA) program. Two RTCM options are available:
RTCM/NONE (81a), which allows connection to a beacon receiver with no output
capability; and RTCM/NMEA (81b), which allows DGPS input and NMEA output.
Once a RTCM setting has been selected, the GPS II
+will either automatically try to
tune the last frequency and bit rate you selected or will switch to the default frequency
of 304.0 kHz with a bit rate of 100 bps if no previous beacon has been tuned. You may
also enter your own frequency and bit rate if desired.
To enter a DGPS beacon frequency:
1. Highlight the ÔfreqÕ field, and press ENTER.
2. Enter the desired frequency, and press ENTER.
3. Highlight the ÔrateÕ field, and press ENTER.
4. Select the desired transmission rate, and press ENTER.
Fig. 81a
Fig. 81b
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When the GPS II+is receiving DGPS corrections from the GBR 21, the Ôbeacon receiverÕ sec-
tion of the I/O setup page will display the beacon frequency and signal strength, as well as the
distance from the transmitter to the beacon receiver. At the bottom of the beacon receiver field,
a status message will keep you informed of DGPS activity:
¥ A ÔtuningÕ message will be displayed while a beacon signal is being tuned.
¥ Once the beacon signal has been tuned, a ÔreceivingÕ message will be displayed.
¥ If a beacon signal is tuned and no corrections are being received, a Ôno dataÕ message will
be displayed.
¥ If a beacon signal cannot be tuned, a Ôno statusÕ message will be displayed.
The message page will alert you to any problems relating to DGPS operation. You may also
monitor the DGPS status from the status field on the interface page. The GPS II+
will display
one of three alert messages concerning DGPS operation:
No DGPS PositionÑ there is not enough data available to compute a DGPS position.
No RTCM InputÑthe beacon receiver is not properly connected or the baud rates do not
match.
RTCM Input FailedÑDGPS data was being received but has been lost.
Reference
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							Reference
83
Fig. 83a
Fig 83b
Navigation Simulator
The GPS II
+Õs simulator mode lets you practice all aspects of its operation without
active satellite acquisition. You can plan and practice trips, enter new waypoints and
routes, and save them for use during normal operation.
To activate the simulator:
1. From the Menu Page, highlight ÔSYSTEM SETUPÕ (Fig. 83a), and press ENTER.
2. Highlight the ÔmodeÕ field, and press ENTER.
3. Select ÔSimulator?Õ (Fig. 83b), and press ENTER.
Once the simulator mode has been activated, use the Position, Compass, or
Highway Page to set your speed and track by highlighting the appropriate field, enter-
ing the desired value, and pressing ENTER. You may also enter a new position if you
desire (from the Position Page). 
The GPS II+ does not track satellites in simulator mode. Although you can
create and save waypoints and routes while using the simulator mode,
never attempt to use the simulator mode for actual navigation.#!
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Dashboard Mounting
The GPS II
+can be mounted on the dashboard of an automobile or to another convenient surface using the
two Velcroªstrips provided with the unit. 
To mount the GPS II
+using the Velcro strips:
1. Select a location for the unit that provides a clear and unob-
structed view of the sky.
2. Remove the paper strip liners from both pieces of Velcro.
3. Make sure the surface to which youÕre adhering the Velcro is
clean and dry. Place the adhesive side of the rough piece of
Velcro on the desired mounting surface, and press into place. 
4. Place the adhesive side of the smooth piece of Velcro on the
bottom of the unit (between the rubber anti-skid bumps), and
press into place.
5. Mount the unit, placing one piece of Velcro on top of the other.
Appendix A
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