Lowrance electronic X-55A ) -a

you

find noise interference from an electrical instrument, trolling

motor,

pump, or

radio, tryto isolatethe

problem.

You can

usually

reroutethe sonar

unit's power cable and transducer cable away from the wiring that is

causing the interference. VHF radio antenna cables radiate noise when

transmitting, so be certain to

keep

the sonar's wires

away

from 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 unitfrom

electrical equipment, then make

certain

everything exceptthe sonar unit is turned off,

then startthe

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,

or tachometer

wiring. Try using

resistor spark

plugs, alternator filters,

routing

the sonar unit'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 function 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 X-55A are shown on the

following

pages. To view these groups, simply press the

WINDOWS key, then

repeated press

the down arrow

key. This will "cycle" the unit

through all

groups. Remember, each

group can be customized, however the

group

will revert to the ones shown on these

pages when

the unit is turned off.

SHOOT-THRU-HULL INSTALLATION

The transducer installation inside a fiberglass hull must be in an area

that does not have air bubbles in the resin or separated fiberglass

layers. The sonar

signal must pass through solid fiberglass. A success-

ful transducer installation oan be made on hulls with flotation materials

(such as plywood, balsa

wood, or

foam)

between layers

of

fiberglass

if

the material is removed from the chosen area. For example, some

manufacturers use a layer of fiberglass, then a core of balsa wood,

finishing with an outer layer

of fiberglass. Removing the inner layer

of

fiberglass

and the balsa wood core

exposes the outer

layer

fiberglass.

The transducer can then be epoxied directly

to the outer layer

of fiber-

glass.

After

the

epoxy

cures, the hull is

watertight and structurally sound.

Remember, the

sonar

signal must

pass

through solid

fiberglass. Any

air

bubbles in the

fiberglass

or the epoxy

will reduce or eliminate the sonar

signals.

To choose the proper location for thru-hull mounting, anchor the boat in

60 feet of water. Add a little water to the

sump

of the boat. Plug

the

transducer into the sonar unit,

turn it on, then hold the transducer over

FILL WITH

EPOXY,J?1 INNER HULL

— ) -a

Epoxy TO HULL

FIRST— OUTER HULL

the side of the boat. Adjust the sensitivity and range controls until a

second bottom echo

is seen on the display. (you will need to turn the

automatic function off on L.C.G. units.) Don't touch the controls once

they've

been set. Next, take the transducer out of the water and place

it

in the water in the sump

of the boat. Observe the sonar

signal to see if

there is a noticeable decrease in

sensitivity. The second bottom

signal

may disappear and the bottom signal may

decrease in intensity. Move

the transducer around to find the best

location. If the

sensitivity control

has to be increased greatly

to compensate, then the transducer should

be mounted on the

outside of the hull. If not, then mark the location that

shot through the hull the best and follow the instructions on the next

pages for a shoot-thru-hull mounting.

44 9

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