Eagle Electronics UltraNav II -

major

cause of sonar

problems is electrical noise. This

usually appears

on the

sonar's display as

random

patterns

of dots or lines. In severe

cases,

it can completely

cover

the screen with black dots, or cause the unit

operate erraticly, or

not at all.

To eliminate or

minimize the effects of

electrical noise, firsttryto determine

the cause. With

the boat at rest in

the water, the first thing you should do

is turn all electrical equipment on the boat off. Make certain the engine is

off, also. Turn your UltraNay II on, then turn off ASP (Advanced Signal

Processing). There should be a

steady

bottom signal

on the

display. Now

turn on each

piece

of electrical equipment on the

boat and view the effect

on the sonar's display. For

example, turn on the

bilge pump and view the

sonar

display for noise. If no noise is

present, turn

the

pump off,

then

turn

on the

VHF radio and

transmit.

Keep doing

this until all

electrical

equipment

has been turned on,

their

effect on the sonar

display noted, then turned

off.

you find noise

interference from an

electrical instrument, trolling motor,

pump, or radio, try

to isolate the

problem. You can usually re-route the

sonar unit's

power

cable and

transducer cable

away from the

wiring

that

causing

the interference. VHF

radio antenna cables radiate

noise when

transmitting, so be certain to keep

the sonar's wires awayfrom

it. You may

need to route the sonar

unit's

power

cable

directly

to the

battery

to isolate

it from other

wiring on

the boat.

If no noise

displays on

the sonar unit from electrical equipment, then make

certain

everything except

the sonar

unit is turned

off,

then starithe

engine.

Increase the RPM with the gearshift in neutral. If noise

appears on the

display, the

problem could

be one of three things; spark

plugs,

alternator,

tachometer wiring. Try using resistor spark plugs, alternator

filters,

routing the sonar unjt's power cable away from engine

wiring. Again,

routing the power cable directly

to the battery helps eliminate noise

problems.

Make certain

to use the in-line fuse

supplied

with the unit

when

wiring

the

power

cable to the

battery.

When no noise

appears on the sonar unit after all of the above

tests,

then

the noise source is probably cavitation. Many novices or persons with

limited experience

make hasty

sonar installations which fUhotion

perfectly

in shallow

water, or when the boat is

at rest. In nearly all

cases, the

cause

of the malfunction will

be the location and/or

angle of the transducer. The

face of the

transducer must be

placed in a location that has a

smooth flow

of water at all

boat

speeds. Read

your

transducer owner's manual for

the

best

mounting position.

WINDOWS SUMMARY

All of the window groups used by the

UltraNav II are shown on the

following

pages. To view these groups, simply

press the WINDOWS key, then re-

peated press

the down arrow key.

This

will "cycle' the unit

through all groups.

W E

• S dM1

€oie

5 E

,,,,,iI,,,,nñ,,uuI,,m, ñ

i)1

.61 ,,,,,. r,,,,,,i ,,,,,,l,,,,,, n

ti

GROUP

E

— .2 1MI

DIG 0.09

BRG 170°

QQ?. 3210

BOG 100

NOIISE

GROUP "A"

H .

5 E

1NI

:.S

/

GROUP "B"

NON'ad:p

I FEET I

45.2 fliI

I I

65,4 awjssi

I MPH I

15.4 It'IILESI

2.0

GROUP "C"

I FEET I

51.1

N 36°09.059'

U 95°50.674'

GROUP"F" . GROUP"G"

38 39

PDF compression, OCR, web-optimization with CVISION's PdfCompressor