Eagle Electronics UltraNavGPS jj

CHANGING STARTUP SETFINGS

The UItraNavGPS must be initialized when it's turned

on for the first time.

This is described at the beginning of the GPS section in this manual.

However,

you wish to

change only

one of the

parameters (such as

time),

use the menu features in the "CHANGE SETUP"

menu. To do

this, press

the MENU key,

then

press

the

key adjacent tothe "CHANGE SETU P" label.

The screen shown below appears. ______________________

Using

the menus on this and following menu

pages, you can change the Initial Position,

Time-Date-Time Offset, or Altitude without _____________________

affecting any

other initialization setting. All of ____________________

these menus work identically to the ones

described in the initialization section at the

beginning of the GPS section. Afteryou

make ____________________

achange,

the unit

returnstotheGPSorplotter

screen, however. It doesn't automatically

sequence through the initialization menus. ________ ________

For example, if you move a long distance

(over 100 miles) with the unit off, you may

want to enter a new initial

position

to help

the

UltraNavGPS find the correct

position quicker.

PCF OFFSET

(Position

Correction Factor)

The GPS

navigation system relies

complex

mathematical calculations to

determine yourposition

based on satellite data and otherfactors. One factor

is the Earth's shape. Since the Earth is not a true sphere, variations in the

calculations have to be made to accommodate deviations. To make matters

more complex, not everyone uses the same data to determine what the

deviations are. The size and shape of the ellipsoids that are used to

approximate the earth's surface are

improved

often. This can lead to errors

your navigation device uses

one ellipsoid,

while

your

chart uses a different

one. The term used for these

ellipsoids is "datum."

To reduce the error factor between datum, the UltraNavGPS gives you

the

capability to move or "offset" the

position shown on the

displayto

match one

shown on the chart. The unit adds this offset to all position displays.

GRAYLINE®

GRAYLINE lets you distinguish between strong

and weak echoes. It

"paints" gray

targets

that are strongerthan

preset

value. This allows

you to tell the difference between a hard and soft bottom. For

example,

a soft, muddy

weedy bottom returns a weaker

signal which is shown

with a narrow or no

gray line. A hard bottom

returns a

strong signal

which

causes a wide gray line.

you have two

signals of

equal size, one with

gray

and the other

without,

then the target with gray is the

stronger signal. This helps

distinguish

weeds from trees on the

bottom, or fish from structure.

GRAYLINE® is adjustable. Since GRAYLINE® shows the difference

between strong

and weak signals, adjusting

the

sensitivity may require

different GRAYLINE®

level, also. The level chosen

the UltraNavGPS

poweron

usually adequate

for most conditions. Experiment with

your

unit to find the

GRAYLINE®setting

that's best for

you.

_____ ---20

To adjust GRAYLINE

press the SENS key. The sensitivity menu

appears in the

upper

left side of the

display, while

the GRAYLlNEwitch

label

appears immediately beneath it. First

press

the

key adjacent to the

"SENS GRAY" label. This changes the sensitivity adjust menu to

GRAYLINE® adjust. Now press the

key adjacent

to the up arrow to

increase the

gray level. Press the key adjacent to the down arrow to

decrease it. The

percentage of GRAYLIN

E® in

use

changes as the arrow

keys

are pressed. The bar chart also

gives

graphical indication of the

GRAYLINE® level. You can see

the change on the screen (both

on the

menu and on the chart record) as

you press the

keys. After

you've

made

the

adjustmentr press

the CLEAR key to erase the menu.

ENTER

INITIAL

POS IT ION ENTER

TI P1 E/

DATE

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