851 861 operator's manual d 6.26.1998

7/26/2019 851 861 Operator's Manual d 6.26.1998

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MARINE RADAR

MODEL MODEL 851/861


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"DANGER", "WARNING" and "CAUTION" notices appear throughout this manual. It is the

responsibility of the operator and the installer of the equipment to read, understand andfollow these notices. If you have any questions regarding these safety instructions, pleasecontact a FURUNO agent or dealer.

The level of risk appearing in the notices is defined as follows:

SAFETY INSTRUCTIONS

NGER

This notice indicates a potentiallyhazardous situation which, if notavoided, will result in death orserious injury.

This notice indicates a potentiallyhazardous situation which, if notavoided, could result in death orserious injury.

This notice indicates a potentiallyhazardous situation which, if notavoided, could result in minor ormoderate injury, or property damage.CAUTION

W RNING


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Safety Instructions for the Operator

Use the proper fuse.

Use of a wrong fuse can result in fire orpermanent equipment damage.

Do not use the equipment for other thanits intended purpose.

Personal injury can result if the equipmentis used as a chair or stepping stool, forexample.

Do not place objects on the top of theequipment.

The equipment can overheat or personalinjury can result if the object falls.

UTION

Do not open the equipment.

Hazardous voltage which cancause electrical shock, burn orserious injury exists inside theequipment. Only qualifiedpersonnel should work insidethe equipment.

Wear a safety belt and hardhat when working on theantenna unit.

Serious injury or death canresult if someone falls from

the radar antenna mast.

Stay away from transmittingantenna.

The radar antenna emits mi-crowave radiation which canbe harmful to the human body,particularly the eyes. Neverlook directly into the antennaradiator from a distance ofless than 1 m when the radaris in operation.

Turn off the radar powerswitch before servicing theantenna unit. Post a warn-ing sign near the switchindicating it should not beturned on while the antennaunit is being serviced.

Prevent the potential risk of

someone begin struck by therotating antenna and expo-sure to RF radiation hazard.

W RNING

W RNING

Do not disassemble or modify theequipment.

Fire electrical shock or serious injury can

result.

Turn off the power immediately if waterleaks into the equipment or theequipment is emitting smoke or fire.

Continued use of the equipment can causefire or electrical shock.

Do not place liquid-filled containers onthe top of the equipment.

Fire or electrical shock can result if a liquidspills into the equipment.


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iii

TABLE OFCONTENTS

FOREWORD............................... ivSPECIFICATIONS ....................... v

EQUIPMENT LIST ...................... ixCONFIGURATION OF

MODEL 851/861 ......................... xi

1. PRINCIPLE OF OPERATION

1.1 What is Radar?..................................... 1

1.2 How Ships Determined Position BeforeRadar .................................................... 11.3 How Radar Determines Range ............ 11.4 How Radar Determines Bearing.......... 11.5 Radar Wave Speed and Antenna Rota-

tion Speed............................................. 11.6 The Radar Display ............................... 1

2. OPERATION

2.1 Control Description ............................. 32.2 Display Indications and Markers ......... 42.3 Turning the Radar On and Off ............. 42.4 Transmitting......................................... 52.5 Selecting the Range ............................. 52.6 Adjusting LCD Backlighting and Display Tone ........................................ 52.7 Adjusting Control Panel Brilliance ...... 52.8 Adjusting GAIN, STC, A/C RAIN and FTC ............................................... 62.9 Tuning the Receiver ............................. 7

2.10 Measuring the Range ......................... 82.11 Measuring the Bearing....................... 82.12 Menu Operation ................................. 92.13 Selecting the Display Mode ..............112.14 The Window Display ....................... 122.15 Selecting the Presentation Mode ..... 122.16 Guard Alarm .................................... 132.17 Suppressing Radar Interference ....... 142.18 Suppressing Noise Interference ....... 152.19 Selecting Pulselength....................... 15

2.20 Off Centering the Display................ 152.21 Echo Trails ....................................... 162.22 The Navigation Data Display .......... 16

2.23 Echo Stretch..................................... 172.24 Selecting Unit of Measurement for Range ......................................... 182.25 Selecting Bearing Reference ............ 182.26 Watchman ........................................ 182.27 Erasing the Heading Marker ............ 192.28 Deselecting Ranges.......................... 19

2.29 Displaying Navigation During Stand-by ........................................... 192.30 Outputting Cursor Position to Navigator ......................................... 202.31 Displaying Cursor Position, Range and Bearing to Cursor ...................... 202.32 Visual Alarm Indications ................. 20

3. INTERPRETING THE DISPLAY

3.1 The Radar Wave and Radar Horizon . 213.2 Target Properties and Radar Wave Reflection........................................... 213.3 Range Resolution ............................... 223.4 Bearing Resolution ............................ 223.5 False Echoes ...................................... 223.6 Nautical Chart and Radar Picture ...... 24

4. MAINTENANCE &

TROUBLESHOOTING

4.1 Preventative Maintenance.................. 254.2 Replacing the Fuse............................. 254.3 Troubleshooting ................................. 264.4 Self Test ............................................. 27

5. INSTALLATION

5.1 Antenna Unit Installation ................... 285.2 Display Unit Installation .................... 31

5.3 Installation Check List ....................... 355.4 Initial Adjustment of Picture.............. 365.5 Displaying the Installation Menus ..... 365.6 Entering Initial Settings ..................... 375.7 Relative Bearing Alignment .............. 375.8 Sweep Timing .................................... 385.9 Closing the Installation Menus .......... 38

OUTLINE DRAWINGS..............D-1

SCHEMATIC DIAGRAMS......... S-1


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iv

FOREWORD

Congratulations on your choice of theFURUNO MODEL 851/MODEL 861 Ma-rine Radar. We are confident you will see

why the FURUNO name has become syn-onymous with quality and reliability.

For over 40 years FURUNO Electric Com-pany has enjoyed an enviable reputation forinnovative and dependable marine electron-ics equipment. This dedication to excellenceis furthered by our extensive global networkof agents and dealers.

Your radar is designed and constructed to

meet the rigorous demands of the marine en-vironment. However, no machine can per-form its intended function unless properlyinstalled and maintained. Please carefullyread and follow the recommended proce-dures for installation, operation and main-tenance.

While this unit can be installed by the pur-chaser, any purchaser who has doubts abouthis or her technical abilities may wish to

have the unit installed by a FURUNO rep-resentative or other qualified technician. Theimportance of a thorough installation can-not be overemphasized.

We would appreciate hearing from you, theend-user, about whether we are achievingour purposes.

Thank you for considering and purchasingFURUNO equipment.

Features

Your radar has a large variety of functions,all contained in a remarkably small cabinet.

The main features of the MODEL 851/MODEL 861 are:

Traditional FURUNO reliability andquality in a compact, lightweight andlow-cost radar.

Smartly styled, light-weight and compactradome antenna fits even on small yachts.

Durable brushless antenna motor.

High definition 8" LCD raster-scan dis-play.

On-screen alphanumeric readout of all

operational information. Standard features include EBL (Elec-

tronic Bearing Line), VRM (VariableRange Marker), Guard Alarm, DisplayOff Center and Echo Trail.

Watchman feature periodically transmitsthe radar to check for radar targets whichmay be entering (or exiting) the alarmzone.

Operates on 10.2 to 31.2 V DC powersupply and consumes about 40 W (851);50 W (861, 24 rpm); and 70 W (861, 48rpm).

Ships position in latitude and longitude(or Loran C Time Differences), range andbearing to a waypoint, ships speed, head-ing and course can be shown in the bot-tom text area. (Requires a navigation aidwhich can output such data in NMEA

0183 format.) Zoom feature provided.

Omnipad controller makes the selectionof target and menu items easy.


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v

SPECIFICATIONS

MODEL 851

Antenna Unit

1. Radiator

Slotted waveguide array2. Radiator length

100 cm

3. Horizontalbeamwidth2.4

4. Vertical beamwidth

27

5. Sidelobe

Less than -24dB6. Polarization

Horizontal7. Antenna rotation speed

24 rpm

8. Wind resistance

Relative wind speed 100 kts (51.5 m/s)

Transceiver Module(contained in antenna unit)

1. Transmitting tube

Magnetron E3571 or MG52482. Frequency &modulation

9410 MHz 30MHz, P0N (X band)

3. Peak output power

4 kW4. Pulselength & pulse repetition rate

0.08s, 2100 Hz (0.125, 0.25, 0.5,

0.75, 1, 1.5 nm)0.3s, 1200 Hz (1.5, 2, 3 nm)0.8s, 600 Hz (3, 4, 6, 8, 12, 16, 24,36, 48 nm)

5. Warm-up time

2:306. Modulator switching method

FET

7. I. F.

60 MHz

8. TuningAutomatic or manual

9. Receiver front end (Microwave IC)

MIC10. Bandwidth

7 MHz

11. Duplexer

Circulator with diode limiter

Display Unit

1. Indication system

PPI raster scan2. Display

8-inch diagonal LCD, STN semi-transparent, yellow mode

3. Range scales (nm)

Range, Ring Interval: 0.125(0.0625),

0.25(0.125), 0.5(0.125), 0.75(0.25),1(0.25), 1.5(0.5), 2(0.5), 3(1), 4(1),6(2), 8(2), 12(3), 16(4), 24(6), 36(12),48(12)

4. Bearing resolution

2.45. Bearing accuracy

Better than 16. Range discrimination

Better than 25 m

7. Range ring accuracy &discrimination

0.9% or range in use or 8 m,whichever is larger

8. Minimum range

Better than 37 m9. Markers

Heading marker, Bearing scale, Rangering, VRM, EBL, Waypoint (option),Tuning indicator, Alarm zone, Cursor

10. Alphanumeric indicationStandard: Electronic Bearing Line(EBL), Echo Stretch (ES), RainClutter Rejection (FTC), Alarm (G),Interference Rejection (IR), Stand-by(ST-BY), Echo Trail Time (TRAIL),Variable Range Marker (VRM),Range, Range Ring Interval, Rangeand Bearing to Cursor (+), Off Center(OFF CENTER), Watchman

(WATCHMAN)


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8. Tuning

Automatic or manual9. Receiver front end (Microwave IC)

MIC

10. Bandwidth

7 MHz11. Duplexer

Circulator with diode limiter

Display Unit

1. Indication system

PPI raster scan

2. Display

8-inch diagonal LCD, STN semi-transparent, yellow mode

3. Range scales (nm)Range, Ring Interval: 0.125(0.0625),0.25(0.125), 0.5(0.125), 0.75(0.25),1(0.25), 1.5(0.5), 2(0.5), 3(1), 4(1),6(2), 8(2), 12(3), 16(4), 24(6), 36(12),48(12), 64(16)

4. Bearing resolution

1.95. Bearing accuracy

Better than 1

6. Range discriminationBetter than 25 m

7. Range ring accuracy

& discrimination

0.9% or range in use or 8 m,whichever is larger

8. Minimum range

Better than 37 m9. Markers

Heading marker, Bearing scale, Range

ring, VRM, EBL, Waypoint (option),Tuning indicator, Alarm zone, Cursor

10. Alphanumeric indication

Standard: Electronic Bearing Line(EBL), Echo Stretch (ES), RainClutter Rejection (FTC), Alarm (G),Interference Rejection (IR), Stand-by(ST-BY), Echo Trail Time (TRAIL),Variable Range Marker (VRM),Range, Range Ring Interval, Range

and Bearing to Cursor (+), Off Center(OFF CENTER), Watchman

(WATCHMAN)With navigation input (option): Course(CRS), Latitude and longitude, Speed(SPD), Range and bearing to waypoint(WP), Cross Track Error (XTE), Dateand time, Water depth, Watertemperature. (This radar has only two

data input ports. To receive data frommore than two equipment install an

mixing device.)

11. Vibration

Vibration freq. Total amplitude5 to 12.5 Hz 1.6 mm12 to 25 Hz 0.35 mm25 to 50 Hz 0.10 mm

12. Useable temperature

Antenna unit: 20C to +70CDisplay unit: 0C to +60C

Due to the inherent nature of the LCD

its contrast may be affected underambient temperature below 0C (32F)

or above 50C (122F).

13. Useable humidity

Relative humidity 95% or less at+40C

14. Waterproofing

Display unit: IEC IPX5Antenna unit: IEC IPX6

15. Power supply &

power consumption

12 V or 24V(10.2 V to 31.2 V DC),50 W approx.

16. Protection features

Protection against reverse polarity,overvoltage, overcurrent, and internalfault

17. Compass safe distance

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Interface NMEA(MODEL 851/861)

Input

Own ships position :GAA> RMA> RMC> GLL

Speed : RMA>RMC>VTG>VHW

Heading(True):HDT>VHW>HDG>VHW>HDM

Heading (Magnetic):HDM>VHW>HDG>VHW>HDM

Course (True):RMA>RMC>VTG

Course (Magnetic)VTG>RMA>RMC

Waypoint (L/L, Range, Bearing):RMB>BWC>BWR

Loran time difference :RMA>GLC>GTD

Water depth : DPT>DBK, DBS, DBT

Water temperature : MDA>MTW

Time : ZDA

XTE : RMB>XTE>APB

Output

TLL : On using HM OFF key.

RSD : An interval of four seconds


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EQUIPMENT LIST

MODEL 851

emaN epyT .oNedoC ytQ skrameR

tinUyalpsiD 5-711-PDR 1

tinUannetnA 1600-BSR 1

tinUFR 350-RTR 1 tinUannetnAnideniatnoC

annetnArotaidaR

8NX 233-978-000 1

straPerapS 00121-30PS 469-680-000 tes1

seirosseccA 00950-30PF 050-264-800 tes1

noitallatsnIlairetaM

).enotceleS(

00861-30PC 408-680-000tes1

m01:elbaclangiS

01861-30PC 508-680-800 m51:elbaclangiS

02861-30PC 608-680-000 m02:elbaclangiS

03861-30PC 708-680-000 m02:elbaclangiS

MODEL 861


tinUyalpsiD 6-711-PDR 1

tinUannetnA 2600-BSR 1

tinUFR 650-RTR 1 tinUannetnAnideniatnoC

annetnArotaidaR

A21NX 047-912-800 1

straPerapS 00121-30PS 469-680-000 tes1

seirosseccA 00950-30PF 050-264-800 tes1

noitallatsnIlairetaM

).enotceleS(

00861-30PC 408-680-000tes1

m01:elbaclangiS

01861-30PC 508-680-000 m51:elbaclangiS

02861-30PC 608-680-000 m02:elbaclangiS

03861-30PC 708-680-000 m03:elbaclangiS

Optional Equipment


tinUannetnA -5600-BSR

650 064-474800 1

84,168LEDOMroFtinUFRgniatnoCmpr

rezzuBlanretxE 631-30PO 344-680-000 1

refiticeR 3243-UR 344-030-000 1


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Installation Material


rehsaWlaeS XD3501WC 120-058-000 4

tloB.xeH 403SUS06x21M 191-268-000 4

tuN.xeH 403SUS21M 211-368-000 4

rehsaWtalF 403SUS21M 231-468-000 4

rehsaWgnirpS 403SUS21M 362-468-000 4

niPtolS SUS54x01 093-668-000 2

rotcennoCHX )P5(6971-30 038-264-800 1

elbaClangiS

).enotceleS(01-86-30S 004-474-800

1m01

51-86-30S 014-474-800 m51

02-86-30S 024-474-800 m02

03-86-30-S 034-474-800 m03

elbaCrewoP 1339S30 454-831-000 1 m5.3erocIME 52-RS-DSE 303-321-000 1

Spare Parts (SP03-12100)


ESUF V521CAA01OBGF 560-945-000 2 CDV21roF

ESUF V521CAA5A-OBGF 460-945-000 2 CDV23/42roF

)A5(elbaL 0-2151-921-30 087-842-001 1 CDV23/42roF

Accessories (FP03-05900)


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12V: 10A

24V: 5A

NAV

Video Sounder

Gyro Gyro Converter

AD-100

*Equivalent to NMEA0183

Option

IEC 1162*

IEC 1162*

(In/Out)

(In)

Fluxgate HeadingSensor C-2000

Antenna Unit

Remote Display

FMD-8010

FMD-811

External Alarm

Buzzer OP03-136

Rectifier

RU-3423

10.2~31.2VDC 115/230VAC

MODEL 851/861

CONFIGURATION OF

MODEL 851/861


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1. PRINCIPLE OF

OPERATION

1.1 What is Radar?

The term "RADAR" is an acronym mean-ing RAdio Detection And Ranging. Al-though the basic principles of radar weredeveloped during World War II, primarilyby scientists in Great Britain and the UnitedStates, the use of echoes as an aid to navi-gation is not a new development.

1.2 How Ships DeterminedPosition Before Radar

Before the invention of radar, when runningin fog near a rugged shoreline, ships wouldsound a short blast on their whistles, fire ashot, or strike a bell. The time between theorigination of the sound and the returningof the echo indicated how far the ship was

from the cliffs or the shore. The directionfrom which the echo was heard indicatedthe relative bearing of the shore.

1.3 How Radar DeterminesRange

Radar determines the distance to the targetby calculating the time difference between

the transmission of a radar signal and thereception of the reflected echo. It is a knownfact that radar waves travel at a nearly con-stant speed of 162,000 nautical miles persecond. Therefore the time required for atransmitted signal to travel to the target andreturn as an echo to the source is a measureof the distance to the target. Note that theecho makes a complete round trip, but onlyhalf the time of travel is needed to deter-

mine the one-way distance to the target. Thisradar automatically takes this into accountin making the range calculation.

1.4 How Radar DeterminesBearing

The bearing to a target found by the radar isdetermined by the direction in which theradar scanner antenna is pointing when it

emits an electronic pulse and then receivesa returning echo. Each time the scanner ro-tates pulses are transmitted in the full 360degree circle, each pulse at a slightly differ-ent bearing from the previous one. There-fore, if one knows the direction in which thesignal is sent out, one knows the directionfrom which the echo must return.

1.5 Radar Wave Speed andAntenna Rotation Speed

Note that the speed of the radar waves outto the target and back again as echoes is ex-tremely fast compared to the speed of rota-tion of the antenna. By the time radar echoeshave returned to the scanner, the amount ofscanner rotation after initial transmission ofthe radar pulse is extremely small.

1.6 The Radar Display

The range and bearing of a target is displayedon what is called a Plan Position Indicator(PPI). This display is essentially a polar dia-gram, with the transmitting ships positionat the center. Images of target echoes arereceived and displayed at their relative bear-

ings, and at their distance from the PPI cen-ter.

With a continuous display of the images oftargets, the motion of the transmitting shipis also displayed.


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A

BC

D

Own ship(radar)

DA

BC

Heading markerTargets

Own shipin center

Range and bearingof a target, relativeto own ship, arereadable on the PPI.

(A) Bird's eye view of situation (B) Radar picture of (A)

Figure 1-1 How radar works


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2. OPERATION

2.1 Control Description

OmnipadShift cursor, VRMand EBL; selectitems and options

on menu.

Selects display mode;erases heading error

indication.

Turns power on/off.

Adjusts display brilliance.

Sets radar in stand-by;transmits radar pulse.

Selects radar range.

Plots targets' trails.

Opens/closes menus.

Turns the VRM on/off.Turns the EBLon/off.

ENT MENU

ECHOHMOFF

RANGE

TONE BRILL

EBL VRM

TRAIL RINGS

GUARD OFFCENTER

DISPMODE

ST-BYTX

POWER

Erases heading marker;selects cursor data (Lat/Long, R/B);outputs cursor position.

Turns the rangerings on/off.

Off centersthe display.

Sets guardzone area.

Adjusts displaytone.

Press to adjust gain,A/C RAIN, STC

and FTC.

Registers selectionon menus.

Figure 2-1 Control panel


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2.4 Transmitting

After the power is turned on and the mag-netron has warmed up, ST-BY (Stand-By)appears at the screen center. This means theradar is now fully operational. In stand-by

the radar is available for use at anytimebut no radar waves are being transmitted.

Press the [ST-BY TX] key to transmit. Whentransmitting, any echoes from targets appearon the display. This radar displays echoes infour tones of gray according to echo strength.

When you wont be using the radar for anextended period but want to keep it in a stateof readiness, press the [ST-BY TX] key to

set the radar in stand-by.

2.5 Selecting the Range

The range selected automatically determinesthe range ring interval, the number of rangerings, pulselength and pulse repetition rate,for optimal detection capability in short tolong ranges.

Procedure

Press the [ RANGE +] key. The range andrange ring interval appear at the top left cor-ner on the display.

Tips for selecting the range

When navigating in or around crowded

harbors, select a short range to watch forpossible collision situations. If you select a lower range while on open

water, increase the range occasionally towatch for vessels that may be headingyour way.

2.6 Adjusting LCDBacklighting and DisplayTone

The [BRILL] key adjusts the LCD back-lighting in eight levels, including off. The[TONE] key adjusts the tone (contrast) ofthe display in 32 levels, including off.

Procedure

1) Press the [BRILL] key (or [TONE] key).The display shown in Figure 2-3 appears.

BRILL

DOWN

BRILL

UP

TONE

DOWN

19 7

Item selectedfor adjustment

Tonesetting

TONEUP

LCD brilliancesetting

Figure 2-3 Display for adjustment ofbrilliance and tone

2) Press the [BRILL] key (or [TONE] key)

to set level. For fine adjustment, presscursor pad at 12o'clock/6 o'clock for bril-liance and 3o'clock/9o'clock for tone.

2.7 Adjusting Control PanelBrilliance

Procedure

1) Press the [MENU] key.

2) Press the omnipad to select Backlight/Brilliance and press the [ENT] key.

3) Press the omnipad to select Panel.

4) Press the omnipad to select brilliancelevel; 4 is the highest.

5) Press the [ENT] key followed by the[MENU] key.


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2.8 Adjusting GAIN, STC, A/CRAIN and FTC

General procedure

The [ECHO] key enables adjustment of the

gain, STC, A/C RAIN and FTC.1) Press the [ECHO] key. The following dis-

play appears.

AUTO 1 2 3MAN

AUTO 1 2 3MAN

GAIN

STC

[

[

A/C RAIN 00 FTC 0 1 2

12ECHO KEYTO EXIT

Currentlevel


Figure 2-4 Display for adjustment ofGAIN, STC, A/C RAIN and FTC

2) Press the omnipad to select item to ad-

just. Current selection is circumscribedby dashed rectangle.

3) Press [ENT].

3) Press the omnipad to set level.

4) Press the [ECHO] key to finish.

How to adjust the gain (sensitivity)

The gain works in precisely the same man-

ner as the volume control of a broadcast re-ceiver, amplifying the signals received.

You can adjust the gain automatically ormanually. For manual adjustment, adjust thesensitivity on the highest rangethe back-ground noise is clearer on that range. Theproper setting is such that the backgroundnoise is just visible on the screen. If you setup for too little gain, weak echoes may bemissed. On the contrary excessive gain

yields too much background noise; strongtargets may be missed because of the poor

contrast between desired echoes and thebackground noise on the display.

How to adjust STC (suppressing seaclutter)

Echoes from waves can be troublesome,covering the central part of the display withrandom signals known as sea clutter. Thehigher the waves, and the higher the scan-ner above the water, the further the clutterwill extend. Sea clutter appears on the dis-play as many small echoes which might af-fect radar performance. (See the left-handfigure in Figure 2-5).

The STC reduces the amplification of ech-

oes at short ranges (where clutter is the great-est) and progressively increasesamplification as the range increases, so am-plification will be normal at those rangeswhere there is no sea clutter. The control iseffective up to about 4 miles.

STC can be adjusted automatically or manu-ally. For manual adjustment, first adjust thegain and then transmit on short range. Ad-

just the STC level such that the clutter isbroken up into small dots, and small targetsbecome distinguishable. If the setting is settoo low, targets will be hidden in the clutter,while if it is set too high, both sea clutterand targets will disappear from the display.In most cases adjust so clutter has disap-peared to leeward, but a little is still visiblewindward.

If there is no clutter visible on the display,

turn off the circuit.

Sea clutter atdisplay center STC adjusted;sea clutter suppressed.

Figure 2-5 Effect of STC


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How to adjust A/C RAIN and FTC(suppressing rain clutter)

The vertical beamwidth of the scanner is de-signed to see surface targets even when theship is rolling. However, by this design theunit will also detect rain clutter (rain, snow,hail, etc.) in the same manner as normal tar-gets. Figure 2-6 shows the appearance of rainclutter on the display.

Adjusting A/C RAIN

When rain clutter masks echoes over a widerange, raise the A/C RAIN slightly to dis-tinguish targets from the clutter.

Appearance ofrain clutter

A/C RAIN adjusted;rain clutter suppressed.

Figure 2-6 Effect of A/C RAIN

Adjusting FTC

To suppress rain clutter from heavy stormsor scattered rain clutter, adjust the FTC. TheFTC circuit splits up these unwanted ech-oes into a speckled pattern, making recog-nition of solid targets easier. FTC andselected level appear at the top right-handcorner of the display when the circuit isturned on.

Note:In addition to reducing clutter, the FTCcan be used in fine weather to clarify the pic-ture when navigating in confined waters. How-ever, with the circuit activated the receiver isless sensitive. Therefore, turn off the circuitwhen its function is not required.

2.9 Tuning the Receiver

The receiver can be tuned automatically ormanually. For automatic tuning the receiveris tuned each time you switch from stand-by to transmit. For manual tuning, the re-

ceiver is properly tuned when the longesttuning indicator appears. (However, thelength of the indicator changes with the num-ber of radar echoes, range and other factors.)

Figure 2-7 Tuning indicator

Manual tuning

The default tuning method is automatic. Toswitch to manual tuning;

1) Press the [MENU] key to open the menu.

2) Press the cursor pad to select Tuning.

3) Press the cursor pad to select MANUAL.


How to tune manually

While pressing and holding down the [HM

OFF] key, press the 9 o'clock or 3o'clockposition on the omnipad to tune. Tune toshow the longest tuning indicator.

1.5NM0.5

AUTO

Tuningindicator


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1.5NM0.5

VRM

range

VRM

Target

VRM EBL + CURSOR

0.675NM 220.9R 0.675NM 308.7R

Figure 2-8 Measuring range by the VRM

2.11 Measuring the Bearing

There are two ways to measure the bearingto a target: by the cursor, and by the EBL(Electronic Bearing Line).

By cursor

Operate the omnipad to bisect the target withthe cursor intersection. The bearing to thetarget appears at the bottom right-handcorner of the display.

By EBL

1) Press the [EBL] key to display the EBL.2) Press the omnipad to bisect the target with

the EBL. (The cursor appears and islinked with the EBL, allowing you tomeasure both bearing and range to thetarget.)

3) Check the EBL readout at the bottom left-hand corner of the display to find the bear-ing to the target.

Note: The EBL is automatically anchored whenno omnipad key is operated within about 10

seconds.

2.10 Measuring the Range

You can measure the range to a target threeways: by the range rings, by the cursor, andby the VRM (Variable Range Marker).

By range rings

Press the [RINGS] key to display the rangerings. Count the number of rings betweenthe center of the display and the target.Check the range ring interval (at the top leftcorner) and judge the distance of the echofrom the inner edge of the nearest ring.

By cursor

Operate the omnipad to place the cursor in-tersection on the inside edge of the targetecho. The range to the target, as well as thebearing, appears at the bottom of the dis-play.

By VRM

1) Press the [VRM]key to display the VRM.

2) Press the omnipad to place the VRM onthe inside edge of the target. (The cursorappears and is linked with the VRM,allowing you to measure both range andbearing to the target.)

3) Check the VRM readout at the bottomleft-hand corner of the display to find therange to the target.

Note:The VRM is automatically anchoredwhen no omnipad key is operated within about

10 seconds.

To erase the VRM,press and hold downthe [VRM] key for about three seconds.


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9

To erase the EBL,press and hold down the[EBL] key for about three seconds.

1.5NM0.5

EBL

Target

EBLbearing

VRM EBL + CURSOR

0.675NM 300.1R 0.675NM300.1R

Figure 2-9 Measuring bearing by the EBL

Tips for measuring the bearing

Bearing measurements of smaller targetsare more accurate; the center of larger tar-get echoes is not as easily identified.

Bearings of stationary or slower movingtargets are more accurate than bearingsof faster moving targets.

To minimize bearing errors keep echoesin the outer half of the picture by chang-ing the range scale; angular difference be-comes difficult to resolve as a targetapproaches the center of the display.

Target on collision course with yourvessel?

You can determine if a target might beon a collision course with your vessel byplacing the EBL on the target. If it tracksalong the EBL as it approaches thescreen center it may be on a collisioncourse with your vessel.

2.12 Menu Operation

The menu, consisting of 6 sub menus, mostlycontains less-often used functions whichonce preset do not require regular adjust-ment. To open or close the menu, press the

[MENU] key. You can select items on themenu with the omnipad.

Basic menu operation

1) Press the [MENU] key to open the menu.The main menu appears.

MAIN MENU

Select item by keysand press ENT key.1. Backlight/Brilliance2. P/L, IR, NR & Radar Mode3. Nav Data4. Mode & Function5. Tuning AUTO MANUAL6. Self Check7. Installation Setup 1

. . . . . . . . . . . . . . . . .Press HM-OFF to temporarilyhide menu.

Figure 2-10 Main menu

2) Press the omnipad to select menu andpress the [ENT] key.

3) Press the omnipad to select menu item.

4) Press the omnipad to select option.

5) Press the [ENT] key to register selection.

6) Press the [MENU] key to close the menu.

Menu description

See the table on the next page.


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Table 1-1 Menu description

Menu Function

1. Selects control panel backlighting; four is maximum backlighting.2. Selects brilliance for echo trails and markers; four is maximum brilliance.

1. Selects pulselength for 1.5 and 3 mile ranges.2. Selects radar interference rejector level; 3 provides highest degree of rejection.3. Turns noise rejector on/off.4. Turns echo stretch on/off.5. Select mode for CU or WPT-UP.

1. Selects navigator among GPS, Loran and all navigators available. In the "All" setting the radar selects a navigator in order of navigator accuracyGPS, Loran and other.2. Turns navigation data display on/off.

3. Selects position display format; latitude and longitude or Loran TDs.4. Selects unit of measurement for depth; meters, feet or fathoms.5. Selects unit of measurement for water temperature; C or F.6. Selects what to display during stand-by; navigation data (requires navigation input) or "STBY".

1. Selects window display format; zoom or wide.2. Selects watchman interval among 5 min, 10

min or 20 min.3. Selects alarm mode; IN (alarm to targets entering the guard zone, or OUT (alarm to targets exiting the guard zone.4. Selects VRM unit; nm, km or sm.5. Selects EBL reference; relative or true.6. Selects ranges to use. Select range to enable (disable) and press [ENT] key.* Model 841 only

Tuning Selects AUTOMATIC or MANUAL tuning.

* Default settings shown in boldface.

1. BACKLIGHT/BRILLIANCE MENU

Select item and optionby keys.

1. Panel2. Echo Trails

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Press HM-OFF to temporarilyhide menu.

1 2 3 41 2

2. P/L, IR, NR & RADAR MODE

Select item and optionby keys.1. Pulselength2. Int Reject3. Noise Reject4. Echo Stretch5. Radar mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Press HM-OFF to temporarilyhide menu.

SHORT LONGOFF 1 2 3OFF ONOFF ONCU WPT-UP

3. NAV DATA MENU

Select item and optionby keys.1. Navigator

2. Nav Data Disp3. Pos Disp Mode4. Depth Unit5. Temp Unit6. STBY Display. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Press HM-OFF to temporarilyhide menu.

ALL GPS LC

OFF ONL/L TDM FA FTC FNORM NAV

Select item and optionby keys.

1. Window Display2. Watchman3. Alarm Mode4. VRM Unit5. EBL Ref6. Range

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Press HM-OFF to temporarilyhide menu.

ZOOM WIDEOFF 5' 10' 20'IN OUTNM KM SMREL TRUE

4. MODE & FUNCTION MENU

1/8 1/4 1/2 3/4 1 1/52 3 4 8 12 16 24 *36

Self Check Checks the radar system for proper operation.


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2.13 Selecting the DisplayMode

The display mode may be selected with the[DISP MODE] key. Four modes are avail-able (with navigation input): Normal, Nor-

mal + Window, Normal + Nav Data, andNormal + Window + Nav Data.

Each time the key is pressed the displaymode changes in one of the sequences shownbelow, depending on equipment connectedand menu settings.

Note:In the window display mode, the [DISPMODE] key reselects zoom area. To select thedisplay mode while in the window displaymode, press the key twice.

Window DisplayNav Display

WIDE / ZOOMON / OFF

VRM EBL +CURSOR **.**NM ***.*R ***.**NM ***.*R


ZOOM


WIDE / ZOOMON / OFF

Window DisplayNav Display


ZOOM

Figure 2-11 Display modes


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12

2.14 The Window Display

The window display appears at the bottomright (or left) 1/4 of the display. Two typesof window displays are available: zoom andwide. Zoom doubles the size of the area se-

lected by the operator, and wide (range-up)compresses and displays the entire radar pic-ture on the next higher range.

Note 1:The zoom display does not functionon the 0.125 and 0.25 nm ranges.

Note 2:The wide display does not function onthe 48 and 64(861) nm.

Selecting the type of window display


2) Select Mode & Function and press the[ENT] key.

Note: When you place the circle cursorbehind the window display, the windowdisplay shifts left (or right) so you may viewthe circle cursor.

3) Select Window Display to Zoom or Wide

(range-up).4) Press the [ENT] key followed by the

[MENU] key.

Selecting the area for the zoom picture

1) Press the [DISP MODE] key to select thewindow display. The area selector is asolid circle.

2) Press the omnipad to place the circle cur-sor (area selector) on the area to zoom.

3) Press the [ENT] key. The area selectorbecomes a dashed circle and the cursorcan be moved indepedently.

To reselect area to zoom, press [ENT] or[DISP MODE] and follow steps 2 and 3.

Figure 2-12 How to selectthe area to zoom

2.15 Selecting the PresentationMode

This radar provides four presentation modes:head-up, course-up (course-up or waypoint-up; selectable on menu), north-up and truemotion. Press the [DISP MODE] and [HMOFF] keys together to select a presentationmode. Each time the keys are pressed, ifheading signal is input to the radar, the pre-sentation mode changes in the sequence ofHU, CU (or WU), NU, TM. If there is noheading signal input to the radar, the pre-sentation mode is always HU.

Note:TM does not function on the 48 and64(861) nm.

Selecting course-up mode for CU orWPT-UP

You may select WPT-UP instead of CU onthe menu.

CU (course-up)

An azimuth stabilized display in which theline connecting the center with the top ofthe display indicates own ships intendedcourse.


Window

displayarea


(1) Press [DISP MODE]to select the windowdisplay.

Area selector (1/4 or 1/3 of range)

(2) Press cursor keysto select area to zoomand press [ENT].

HU(head-up)

CU(couse-up)

WPT-UP(waypoint-up)

NU(north-up)

TM

(true motion)


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WPT-UP (waypoint-up)

An azimuth stabilized display in which theline connecting the center with the top ofthe display indicates the bearing to the TOwaypoint, which is selected on the naviga-

tional equipment connected to the radar.When navigating a route and own ship en-ters the arrival zone of a waypoint, the ra-dar displays the bearing to the next TOwaypoint.

Procedure

1. Press the [MENU] key to open the menu.

2. Press the cursor pad to select 2. P/L, IR,NR & Radar Mode.

3. Press the omnipad to select Radar mode.

4. Select option for CU or WPT-UP.

5. Press the [ENT] key followed by the[MENU] key.

2.16 Guard Alarm

The guard alarm allows the operator to setthe desired range and bearing for a guardzone. When ships, islands, landmasses, etc.enter (or exit, depending on type of guardzone in use.) the guard zone an audible alarmsounds to call the operators attention. Thealarm is very effective as an anticollisionaid when using an autopilot or navigatingin narrow channels.

Selecting guard zone type

The guard alarm can be set to sound on tar-gets entering (guard in) or exiting (guard out)the guard zone. Select type of guard zoneas follows.

1) Press the [MENU] key to display themenu.


3) Select Alarm Mode to IN or OUT.


Dashed line:

no alarm

IN ALARM OUT ALARM

Guard

zone

Figure 2-13 In and out alarms

Setting the guard zone

1) Mentally create the guard zone you wantto display. See Figure 2-14 (1).

2) Operate the omnipad to set cursor on top(bottom) left edge of the guard zone. Pressthe [GUARD] key. *G (IN) (or G OUT)),with asterisk blinking, appears at the topright-hand corner on the display. (Theasterisk indicates the guard zone is par-

tially set.) See Figure 2-14 (2).3) Operate the omnipad to set cursor on bot-

tom (top) right edge of the guard zoneand press the [GUARD] key. The aster-isk disappears. See Figure 2-14 (3).

4) Guard zone appears on the display. SeeFigure 2-14 (4).

Silencing the audible alarm

Any ships, landmasses, etc. coming into (orgoing out of) the guard zone will trigger theaudible alarm and display the guard zone in

CAUTIONThe guard alarm is a useful anti-collision aid, butdoes not relieve the operator of the responsibilityto also keep a visual lookout for possiblecollision situations. The alarm should never beused as the sole means for detecting possiblecollision situations.


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reverse video. You can silence the alarm bypressing the [GUARD] key. When this isdone, G (ACKN) replaces G (IN) (or G(OUT)).

Press the [GUARD] key again to reactivate

the alarm. G (IN) (or G (OUT)) replaces G(ACKN).

Canceling the guard zone

Press and hold down the [GUARD] key untilthe guard zone disappears.

Notes on the guard alarm

When the radar range is less than one halfof the guard zone range, the guard zonedisappears from the display and UPRANGE appears. If this happens, raisethe range to redisplay the guard zone.

A target echo does not always mean alandmass, reef, ships or surface objectsbut can imply returns from sea surface or

precipitation. As the level of these returnsvaries with environment, the operatorshould properly adjust the STC, gain (sen-sitivity), A/C RAIN and FTC to be surethe alarm system does not overlook tar-get echoes.

Guard zoneto set

* G (IN)

(2) Drag cursor totop left corner ofzone and press[GUARD].

Asterisk blinking

Drag cursorhere.

(1) Mentally createthe guard zone to set.

G (IN)

(3) Drag cursor tobottom right corner

of zone and press[GUARD].

(4) Guard zonecompleted.

G (IN)

Guardzone

Drag cursorhere.

Figure 2-14 How to set a guard zone

2.17 Suppressing RadarInterference

Radar interference may occur when near an-other shipborne radar operating in the samefrequency band as your radar. Its on-screenappearance is many bright dots either scat-tered at random or in the form of dotted linesextending from the center to the edge of the

display. Figure 2-15 illustrates interferencein the form of curved spokes. Interferenceeffects are distinguishable from normal ech-oes because they do not appear in the sameplace on successive rotations of the scan-ner.

Figure 2-15 Radar interference

Four levels of interference are available, in-cluding off: IR1, IR2, IR3 and OFF. IR3provides the highest level of rejection.

Procedure


2) Select P/L, IR, NR & Radar Mode andpress the [ENT] key.

3) Select INT REJECT.

4) Select level desired; 2 provides the great-est degree of interference rejection

5) Press [ENT] and [MENU].


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IR and level selected appear at the top rightcorner on the display when the interferencerejection circuit is turned on.

2.18 Suppressing NoiseInterference

Noise interference appears on the screen asmany bright dots. These dots can be sup-pressed by turning on the noise rejector. Notehowever that there are some forms of noiseinterference which this radar cannot sup-press.

Procedure1) Press the [MENU] key.


3) Select Noise Reject to ON.


2.19 Selecting Pulselength

Pulselength is the transmission time of asingle radar pulse. The longer thepulselength the greater the detection rangecapability, however range accuracy andrange resolution are reduced.

Pulselength can be selected to short or longon the 1.5 and 3 nautical mile ranges.



3) Select Pulselength to SHORT or LONG

4) Press [ENT] and [MENU] key.

Cursor Cursor

(1) Place cursorwhere desired.

(2) Press [OFF CENTER]key; cursor locationbecomes screen center.

2.20 Off Centering the Display

Note:This function is not available on 48 and64nm.

Your vessels position can be shifted any-

where within 75% of the effective displayarea. The primary advantage of the off cen-tered display is that for any range setting,the view ahead of your vessel can be ex-tended without changing the range or sizeof targets.

Procedure

1) Locate the cursor where you want to thescreen center to be.

2) Press the [OFF CENTER] key.

OFF CENTER appears at the top left corneron the display when the display is off cen-tered.

Note:The off centered display is automaticallycanceled when the [DISP MODE] key ispressed.

Figure 2-16 Off centering the display


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2.21 Echo Trails

You can show the trails of targets in after-glow. This function is useful for alerting youto possible collision situations.

Starting echo trail

Press the [TRAIL] key to start the echo trailfunction. Afterglow starts extending fromtargets and "TRAIL" and the echo trail timeappear at the top right-hand corner of thedisplay. Press the key again within 3 sec-onds to select a different trail time, among15 sec, 30 sec, 1 min, 3min, 6 min, 30 min,and continuous. In continuous plotting the

time elapsed appears at the top right corneron the display.

Note: If the range is changed, trails are painted

anew with the newly selected range.

True trails Relative trails(requires gyro)

Figure 2-17 Appearance of echo trails

Fixed time trails

When the elapsed time clock counts up to

the trail time selected, the elapsed time dis-play freezes. The oldest portions of trails areerased so only the latest trail, equal in lengthto the trail time selected, is shown. Then,trails start extending again. For example, theone minute trail time is selected. When theelapsed time display freezes at 60 seconds,all but the latest one minute of trails areerased and then trailing continues.

Continuous trail

The maximum continuous trail time is 99minutes and 59 seconds. When the elapsedtime clock counts up to that time the elapsedtime display is reset to zero all trails are

erased and then trailing is restarted.

Adjusting brilliance of afterglow

The brilliance of the trails' afterglow can beset on the Backlight/Brilliance menu.


2) Select Backlight/Brilliance and press the[ENT] key.

3) Select Echo Trails.4) Select brilliance.


Canceling echo trails

Press the [TRAIL] key to erase the TRAILindication.

2.22 The Navigation DataDisplay

Navigation data can be displayed at thescreen bottom if this radar receives naviga-tion input in NMEA 0183 format. Naviga-tion data includes

position in latitude and longitude or Lo-

ran-C time differences (TDs) bearing and range to a waypoint selected

on the navigator cross track error (XTEthe amount in

nautical miles and the direction the ves-sel if off course)

depth speed.

If the navigation data include the destina-tion data, waypoint position is denoted on

the radar display by a dashed ring.


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1.5NM0.5

HDG 326.8

6604. 00N

16604. 00EVRM EBL + CURSOR

0.675NM 240.1R 0.646NM 308.7R

DEPTH XTE SPD

350.0m 0.05NML 30.0KTWAYPOINT POSI L/L

12.0NM 45.0M

AUTO

Figure 2-18 Sample nav data display

Setting up the nav data display


2) Select Nav Data and press the [ENT] key.

NAV DATA MENU

Select item and optionbykeys.1. Navigator2. Nav Data Disp3. Pos Disp Mode4. Depth Unit5. Temp Unit6. STBY Display


ALL GPS LCOFF ONL/L TDM FA FTC FNORM NAV

Figure 2-19 Nav data menu

3) Select Navigator; GPS, Loran C or ALL(Select all if several navigators are con-nected to the radar. In this case, positiondata is selected in order of GPS, Loran Cand other.)

4) Select Nav Data Disp to OFF or ON.

5) Select Pos Disp Mode to L/L (latitude andlongitude or TD (Loran C).

6) Select unit of depth measurement tometers, fathoms, or feet.

7) Select unit of measurement for water tem-perature to Centigrade or Fahrenheit.

8) Select whether to display nav data or "ST-BY". "NORM" for stand-by; NAv fornavigation data.


2.23 Echo Stretch(magnifying long rangeechoes)

Normally, the reflected echoes from longrange targets appear on the display as weakerand smaller blips even though they are com-pensated by the radars internal circuitry. Tostretch long range echoes, in the range di-rection, turn on the echo stretch function.

Figure 2-20 Echo stretch

Turning echo stretch on or off


2) Select P/L, IR, NR & Radar mode andpress the [ENT] key.

Echo stretch OFF Echo stretch ON

Distantecho


31/57


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Canceling watchman

Press any key while the radar is transmit-ting. (Pressing a key during stand-by causesthe radar to go to warm-up condition.)

2.27 Erasing the HeadingMarker

The heading marker continuously appearson the display and shows your vessels head-ing. When this mark obscures a target echo,you can temporarily erase it by pressing andholding down the [HM OFF] key. Releasethe key to redisplay the marker.

2.28 Deselecting Ranges

This radar has 14 or 15 (MODEL 861)ranges, some which you may not require.You can deselect up to eight ranges as fol-lows.



3) Select Range and press the [ENT] key.Active ranges appear in reverse video.

4) Presstorsto select range to disable(or enable). Current selection is under-lined.

5) Press [ENT].

6) Repeat steps 4 and 5 to disable (or en-able) other ranges.

7) When finished, press the [MENU] key.

2.29 Displaying NavigationData During Stand-by

Various navigation data can be displayedduring stand-by. A barometer is built in this

radar; atmospheric pressure appears, ingraph form, on the navigation data displayduring stand-by. If your navigation aid can

output data in NMEA 0183 data format, yourvessels position in latitude and longitude,the range and bearing to waypoint, speed,course, date, time and cross track error maybe input to this radar, and be seen in the bot-tom text area during stand-by. Further, with

video sounder input, depth may be dis-played, both digitally and in graph form.

Procedure


2) Select the Nav Data menu and press the[ENT] key.

3) Select STBY Display to NAV and pressthe [ENT] key.


Note 1:The depth display scale changes au-tomatically with depth and the maximum depth

is 1,000 meters.

Note 2: The barometer display is updatedhourly, thus the data shown may not be thelatest.

CAUTIONThe barometer and depth displays are intended

as reference. Any data displayed by them

should be used with extreme caution.

Figure 2-22 Navigation data displayduring stand-by

DATE TIME TEMP CRS 08.22 15:19 30.0C 0.0M

DEPTH XTE SPD827 m 0.6NM R 30.0KT

WAYPOINT POSI L/L 6543.98N 16543.96E

XTE

1 100.5 0.5

XTE

(NM)L R

BAROMETER DEPTH

0

500

1000

(m)

12 (MIN)

-12 -9 -6 -3

1020

1010

1000

900

(HOUR)

(hPa)

STBY

12.0NM 114.8R

(Mbar/hPa)


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2.30 Outputting CursorPosition to Navigator

Cursor position (NMEA0183 data sentenceTLL) can be output to the navigator con-nected to this radar by pressing and holdingdown the [HM OFF] key.

2.31 Displaying CursorPosition, Range and Bearingto Cursor

The cursor data indication at the bottom ofthe display can show cursor position in lati-

tude and longitude or the range and bearingfrom own ship to the cursor. You can selectthe indication desired by pressing the [HMOFF] key.

2.32 Visual Alarm Indications

This radar display various visual alarms toalert you to error.

Table 2-1 Visual alarm indications

The heading signal visual alarm may becleared by pressing the [DISP MODE] key.

rorrE mralalausiV

eslupgnidaehoN GNISSIMGISDH

eslupgniraeboN GNISSIMGISPB

langisgnidaeHffodenrut

sraeppa(*.***)gnidaehsa


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Radar horizon

Radar is essentially a line-of-sight phe-nomenon. That means you have just aboutthe same range to horizon with a radar asyou do with your own eyes. However under

normal atmospheric conditions, the radarhorizon is 6% greater than the optical hori-zon. Therefore, if the target does not riseabove the horizon the radar beam cannot bereflected from the target.

The distance to the horizon from the scan-ner, under normal conditions, is calculatedby the following formula.

Rmax = 2.2 x h1 + h2

Where Rmax: Radar horizon (mile), h1: An-tenna height (meters), h2: Target height(meters)

Figure 3-1 Radar horizon

3.2 Target Properties andRadar Wave Reflection

Generally, larger targets can be seen on theradar display at greater ranges, providedline-of-sight exists between the scanner andtarget. However, a large target with poorreflecting properties may not be detected aseasily as a smaller target with better reflect-ing properties. For example, you might ex-pect a lighthouse to be a good radar targetbecause of its size. In actuality the returnecho is weak since the conical shape diffusesmost of the radiated energy.

A ship whose hull is made of conductingmaterials, such as steel, will return a rela-

tively strong echo.

3. INTERPRETING

THE DISPLAY

As an aid to navigation, radar can be a veryvaluable tool. No other electronic naviga-tion aid can give you the ability to spot ves-sels coming at you in the fog, or tell you thelocation of the inlet to the harbor in the pitchblack of night.

To help you understand what your radar can(and cannot) do for you this chapter covers

the characteristics of the radar wave

target properties and radar wave reflec-tion

range and bearing resolution, and

false echoes.

3.1 The Radar Wave andRadar Horizon

How the radar wave travels

The radar wave tends to travel in straightlines at the speed of light. However, it issubject to bending or refraction in the atmo-sphere, the amount depending on region anddensity.

Super-refraction

Super-refraction is a condition in which

there is an upper layer of warm dry air overa surface layer of cold, moist air. Radarwaves bend downward and thus increase theranges at which targets may be detected.

Sub-refraction

Sub-refraction is the reverse condition ofsuper-refraction; a layer of cold air is abovea layer of warm air. Radar waves bend up-ward and thus decrease the ranges at whichtargets may be detected.

D

h

Horizon

Wavepath

h

1

2


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On the other hand, hulls made from woodor fiberglass return much weaker echoes.

Vertical surfaces, such as a cliff, are goodtargets provided they face the radar. Con-versely, horizontal and smooth surfaces such

as mudbanks, sandy beaches, and gentlysloping hills make poor targets because theydisperse rather than reflect most of the en-ergy that strikes them.

The strongest radar echoes known comefrom built-up areas, docks, etc., becausethese targets are less subject to changes inaspect. These types of targets have three flat,smooth surfaces mutually at right angles.Some radar buoys are arranged this way so

as to deliberately increase their detectionrange.

3.3 Range Resolution

Range resolution is a measure of the capa-bility of a radar to display as separate pipsthe echoes received from two targets whichare on the same bearing and are close to-

gether.The main factor which affects range resolu-tion is pulselength. Two targets on the samebearing, close together, cannot be seen astwo distinct echoes on the display unlessthey are separated by a distance greater thanone-half the pulselength.

Figure 3-2 Range resolution

3.4 Bearing Resolution

Bearing resolution is a measure of the capa-bility of a radar to display as separate tar-gets the echoes received from two targetswhich are at the same range and are close

together.

The principal factor which affects bearingresolution is horizontal beamwidth. Two tar-gets at the same range must be separated bymore than one beamwidth to appear as sepa-rate pips.

Figure 3-3 Bearing resolution

3.5 False Echoes

Occasionally false echoes appear on the

screen at positions where there is no target.In some cases the effects can be reduced oreliminated. The operator should familiarizehimself or herself with the appearance andeffects of these false echoes, so as not toconfuse them with echoes from legitimatecontacts.

Multiple echoes

Multiple echoes occur when a short range,strong echo is received from a ship, bridge,or breakwater. A second, a third or more ech-

Target

Transmittedradar

pulse

Transmittedradarpulse

Target

Radar is able to display two

distinct target echoes.

Radar cannot display targets as

separate echoes because they

are within the pulselength.

Direction ofscanner rotation

Target

Horizontalbeamwidth

Direction ofscanner rotation

Horizontalbeamwidth

Radar is able to display twodistinct target echoes.

Radar cannot display targets asseparateechoes because theyare within the beamwidth.

Target


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Indirect echoes

Indirect echoes may be returned from eithera passing ship or returned from a reflectingsurface on your own ship, for example, astack. In both cases, the echo will return from

a legitimate contact to the antenna by thesame indirect path. The echo will appear onthe same bearing of the reflected surface,but at the same range as the direct echo. Fig-ure 3-6 illustrates the effect of an indirectecho. Indirect echoes may be recognized asfollows:

they usually occur in a shadow sector

they appear on the bearing of the obstruc-tion but at the range of the legitimate con-

tact when plotted, their movements are usu-

ally abnormal, and

their shapes may indicate they are not di-rect echoes.

Figure 3-6 Indirect echoes

oes may be observed on the display atdouble, triple or other multiples of the ac-tual range of the target as shown in Figure3-4. Multiple reflection echoes can be re-duced and often removed by decreasing thesensitivity or properly adjusting the STC.

Figure 3-4 Multiple echoes

Side-lobe echoes

Every time the scanner rotates, some radia-tion escapes on each side of the beamcalled side-lobes. If a target exists whereit can be detected by the side-lobes as wellas the main-lobe, the side-lobe echoes maybe represented on both sides of the true echoat the same range, as shown in Figure 3-5.Side-lobes show usually only at short rangesand from strong targets. They can be reducedthrough careful reduction of the sensitivityor proper adjustment of the STC.

Figure 3-5 Side-lobe echoes

Own ship

Target

True

echo

Multiple

echo

Spurious

target

True echoMain-lobe

Side-lobe

Scanner

, ,

, ,

, ,

, ,

, ,

, ,

, ,

,

,

,

,

,

,

Heading

mark

Trueecho

Indirect

echo

Heading

mark

True

echoIndirect

echo

Indirectpath

Direct

path

Scanner

Obstruction

(mast, funnel,

etc.)

Own

ship

Target

Bridge

Direct

path

Indirect

echo

, ,

, ,, ,, ,

, ,,,,,

,,,

,,, ,

, ,,, ,,, ,

, ,, ,, ,

, ,

,

,

,

,,, ,,

,

, ,

, ,, ,

, ,

, ,,,,,

,

,

,

, ,

, ,

Target

,,,, ,, ,,

, ,

, ,

,

,

,

,

,,, ,

, ,

, ,

, ,, ,,

, ,

, ,

,

, ,

, ,

,

,

,,

,

,

,

, ,

, ,

, ,

, ,

, ,

, ,, ,, ,

, ,

, ,

Indirect

path


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24

Blind and shadow sectors

Funnels, stacks, masts, or derricks in the pathof antenna may reduce the intensity of theradar beam. If the angle subtended at thescanner is more than a few degrees a blind

sector may be produced. Within the blindsector small targets at close range may notbe detected while larger targets at muchgreater ranges may be detected. See Figure3-7.

Figure 3-7 Blind and shadow sectors

3.6 Nautical Chart and RadarPicture

Under normal conditions, a picture whichis similar to a nautical chart can be obtainedon the radar display. However, a radar can-

not:

show targets which are below the hori-zon.

show a target which is hidden by a largerone.

see around corners (for example, sea-wall).

distinguish between two targets which arevery close together, either in range orbearing. For example, a vessel towing

another will probably appear as one ves-sel, as both will be covered by the beamat the same time.

The nautical chart and radar picture shownin Figure 3-8 are from the Kada Inland Seain southwestern Japan.

Figure 3-8 Nautical chart and associatedradar picture

Vessel taller

than wharf

Wharf

Wharf

Blind sector

(no echo)

Mast, etc. in path

of radar beam

Size of blind sector

depends on target

size and range.

Actual topography Radar display

Black areas arestrong reflectiontargets.

Coastlinedifficult todisplay.


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25

4. MAINTENANCE &

TROUBLESHOOTING

This chapter tells you how to keep your ra-dar in good working order. Before review-ing this chapter please read the safetyinformation which follows.

4.1 PreventativeMaintenance

Regular maintenance is important for goodperformance. Always keep the equipment asfree as possible from dirt, dust, and watersplashes. Make sure all screws securing thecomponents are properly tightened.

A maintenance program should be estab-lished and should at least include the itemslisted in Table 4-1.

4.2 Replacing the Fuse

The 5A fuse in the power cable protects theequipment against reverse polarity of shipsmains, overcurrent, and equipment fault. Ifthe fuse blows, find the cause before replac-ing it. Never use a fuse rated for more than5Aserious damage to equipment may re-sult and void the warranty.

Turn off the power before per-forming any maintenance ortroubleshooting procedure.

Hazardous voltages can shock, burn or causedeath. Only qualified personnel totally familier withelectorical circuits should work inside the units.

RF RADIATION HAZARDThe radar scanner emits high frequen-cy radio radiation which can be harmful,

particularly to your eyes. Never look directly intothe scanner from a distance of less than two feetwhen the radar is in operation as you could injurethe cornea of your eyes. Always make sure the ra-dar is set to stand-by or is turned off before start-ing work on the scanner unit.

WARNING

doireP metI tniopkcehC skrameR

6ot3shtnom

desopxEdnastun

nostlobtinuannetna

denesoolrodedorrocrofkcehC,yrassecenfI.stlobdnastun

.ylkcihtmehttniaperdnanaelcylivaehfimehtecalpeR

.dedorroc

desuebyamdnuopmocgnilaeSllamsaylppA.tniapfodaetsni

stunneewtebesaergfotnuomanilavomerysaerofstlobdna

.erutuf

annetnArotaidar

noskcarcdnatridrofkcehCdluohstridkcihT.ecafrusrotaidar

htolctfoshtiwffodepiwebafI.retawhserfhtiwdenepmad

thgilsaylppa,dnuofsikcarcrodnuopmocgnilaesfotnuoma

yraropmetasaevisehda.riaperrofllacneht,ydemer

tnevloscitsalpesutonoDuoyfI.gninaelcrof)enoteca(

annetnamorfecievomerotdeenroremmahnedoowaesu,tinunokcarC.remmahdaehcitsalp

retawesuacyamtinuehtsuoiresgnisuac,ssergni

.stiucriclanretniotsegamad

lanimreTdnaspirts

nisgulptinuannetna

kcehcotrevocannetnanepOgulpdnapirtslanimret

kcehcoslA.edisnisnoitcennocannetnafoteksagrebbureht

.noitaroiretedrofsrevoc

nisrevocannetnagnisolcnehWhctacottonluferaceb,noitisopdnasrevocneewtebseriwesool

.tinu

DCL ,emitni,lliwDCLehTtsudfognitaocaetalumucca

.erutcipehtmidotsdnethcihw

tfosahtiwylthgilDCLepiW.htolc

otsrenaelclacimehcesutonoD;tinuyalpsidehtfotrapynanaelc

dnatniapevomernacyeht

.sgnikram

shtnom6raey1ot

tinuyalpsiDsrotcennoc

dnanoitcennocthgitrofkcehC.noisorroc

relaedruoytcatnoc,dedorrocfI.tnemecalperrof

Table 4-1 Recommended maintenance program


39/57


40/57

27

4.4 Self Test

The self test facility checks the keyboard,ROM and RAM for proper operation. Youmay run the test as follows.

1) Press the [MENU] key.2) Select Self Check. The following display

appears.

Figure 4-1 Self test screen

3) To check the keyboard, press a key. Itscorresponding location on the displaylights in black if the key is operating prop-erly.

4) To escape the test, press the [MENU] key.

The ROM and RAM are automaticallychecked. If NG (No Good) appears to the

right of ROM or RAM indication, contactyour dealer for advice.

[SELF TEST]

KEY BOARD TESTPress each key. Cor-responding key onthe screen turnsblack.Prog NO.: 03590951**ROM: OKRAM: OK

On Hours: 000019.5HTx Hours: 000019.5H=MAIN MENU


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5 INSTALLATION

5.1 Antenna Unit Installation

Mounting consideration

When selecting a mounting location for theantenna unit keep in mind the followingpoints.

Install the unit on top of the wheelhouseor on the radar mast on an appropriateplatform. It should be placed where thereis a good all-round view with, as far aspossible, no part of the ship's superstruc-

ture or rigging intercepting the scanningbeam. Any obstruction will cause shadowand blind sectors.

Figure 5-1 Typical antenna unit mounting

location

Locate the antenna base in parallel withthe water surface.

The antenna base is made of aluminum,which will corrode if the mounting plat-form is made of iron. For this reason paintthe mounting platform if it is made of iron.

Do not paint the radiator aperture, to en-sure proper emission of the radar waves.

A magnetic compass will be affected ifplaced too close to the antenna unit. Ob-serve the minimum compass safe dis-tances to prevent deviation of a magneticcompass.

Table 5-1 Compass safe distances

Model Standardcompass

Steeringcompass

851

861

1.1 m 0.8 m

1 m 0.74 m

Mounting

1) Drill four fixing bolt holes (13 millime-ters dia.) , one cable entry hole (approx.50 millimeters dia.) in the mounting plat-form. See the scanner outline drawing onthe back of this manual for hole dimen-sions.

2) Detach the antenna housing cover fromthe scanner housing cover fitted with thetransceiver module can be stored in a con-venient place until the wiring to the an-tenna unit is done.

3) Place the scanner housing on the mount-ing platform and orient it as shown in fig-ure below.

Do not work inside the equip-ment unless totally familiar withelectrical circuits

Hazardous voltage which cancause electrical shock, burn orserious injury exists inside theequipment.

If applicable, turn off the power at themains switchboard before beginning the

installation. Post a sign near the switchto indicate it should not be turned onwhile the equipment is being installed.

Fire, electrical shock or serious injury canresult if the power is left on or is appliedwhile the equipment is being installed.

WARNING


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29

Ship's

bow

Ship's

bow

Figure 5-2 How to orient the antenna unit

4) Insert four M12 x 60 hex head bolts withthe seal washers from inside the scannerhousing, to prevent the bolts from con-tacting the transceiver module.Coat flatand spring washers and nuts and then usethem to fasten the antenna housing to themounting platform. Finally, coat exposedparts of nuts, bolts and flat and spring

washers as shown in Figure 5-3.

Note:Do not turn the bolt to secure the an-tenna housing. Tighten the bolts by the nuttoprevent damage to the seal washer.

Figure 5-3 How to mount the antenna unit

Connections

Only the signal cable runs from the displayunit to the antenna unit. Make the hole for

passing the cable through the bulkhead ordeck at least 20 millimeters diameter. In or-der to minimize the chance of picking upelectrical interference, avoid where possiblerouting the signal cable near other onboardelectrical equipment. Also, avoid running thecable in parallel with power cables. Pass thecable through the hole and apply sealingcompound around the hole for waterproof-ing.

Hex head bolt

(M12 x 60)

Seal washer

Silicone

sealantFlat washer

Spring washer

Hex head nut

Scanner

housing

The procedure for connecting the signalcable to the antenna unit is as following.

1) Through a pipe or waterproof cable grandfitted on the wheelhouse top or bulkhead.

2) Unfasten four screws at bottom of the

scanner base to remove the cable glandassembly.

3) Pass the signal cable through the antennabase and the cable gland assembly (re-moved in step 2.)

Figure 5-4(a) Passing the signal cablethrough the antenna unit

4) Fasten the cable gland assembly.

5) Connect the lead wires to RTB-9100 in

the scanner housing by referring to theInterconnection Diagram at the back ofthis manual. Fasten the shield (inner andouter combined) at the bottom of the an-tenna housing as shown in above figure.

6) Attach the EMI core supplied as shownbelow. The core must be as closer to thecable gland as possible.

Figure 5-4(b) Attachment of the EMI core

CABLECLAMPING

PLATE

A-M4 X 10

FLAT

WASHERPACKING

CABLEGLAND

SHIELD

GROUNDWIRE

Fasten shiledhere.

RTB-9100N Photo No.3081


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30

, ,

, ,

Figure 5-7 Fastening the radiator to theradiator bracket

4) Open the scanner housing cover and fixthe stay as shown in Figure 5-8.

MP Board

Fasten ground

wire here.

Cable

tie

J812

J811

Stay

Figure 5-8 Antenna unit, cover opened

5) One end of the cable with 15-, 9- and 7-way plugs has already been connected toRTB-9100 inside the scanner housing.Mate the 15- and 9- way plugs with jacksJ812 and J811 on the transceiver mod-ule, respectively. Connect the 7-way plugto jack J701 on the MP Board. Secure thecable between RTB-9100 and J701 withthe cable tie as shown in Figure 5-8.

Final preparation

1) Place the scanner housing cover onto theantenna housing. Loosely fasten the fourfixing bolts on the cover.

Scanner housing

cover

Pinning

hole

Fixing

holes

Figure 5-5 Fastening the scanner housing

cover2) Apply grease to the two slot pins. Using

a wooden hammer to prevent damage topaint, inset slot pins into the pinning holesuntil the pin head is flush with the an-tenna housing surface.

Face in

stern direction.

Radiator

bracket

Ship'sbow

Slot pin

Figure 5-6 How to insert slot pins

3) Now is the time to fix the radiator to theradiator bracket. Remove the rubber capat the radiator bracket and orient the ra-diator bracket as shown in below. Refer-

ring to the following figure, apply greaseto the O-ring and set it to the center ofthe radiator bracket. Coat the radiator fix-ing bolts with silicone sealant. Fasten theradiator to the radiator bracket with theFURUNO logo on the radiator facingship's bow.


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31

Even though the picture is quite legibleeven in bright sunlight, keep the displayunit out of direct sunlight or at leastshaded because of heat that can build upinside the cabinet.

Locate the display unit in a position where

you can view and operate it convenientlybut where there is no danger of salt orfresh water spray or immersion.

The orientation of the display unit shouldbe so the radar screen is viewed while theoperator is facing in the direction of thebow. This makes determination of yourposition much easier.

Make sure you allow enough clearanceboth to get to the connectors behind theunit and to allow you to get your handsin on both sides to loosen or tighten themounting knobs. Make sure you leave atleast a foot or so of service loop ofcables behind the unit so it can be pulledforward for servicing or easy removal ofthe connectors.

A magnetic compass will be affected ifplaced too close to the display unit. Ob-serve the minimum compass safe dis-tances to prevent deviation of a magnetic

compass: standard compass, 0.7 meters,and steering compass, 0.5 meters.

Mounting procedure

The display unit is designed to be mountedon a tabletop.

1) Using the hanger as a template, markscrew locations in the mounting location.

2) Fix the hanger to the mounting locationwith four M6 tapping screws (supplied).

3) Fit the knob bolts to the display unit.

4) Install the display unit in the hanger.

5) Tighten the knob bolts securely.

6) Fasten the ground wire (black) of the sig-nal cable to the chassis as shown in Fig-ure 5-8.

7) Loosely fasten the scanner housing cover.You will tighten the fixing bolts after con-firming magnetron heater voltage.

5.2 Display Unit Installation

Mounting considerations

When selecting a mounting location for thedisplay unit keep in mind the followingpoints.

The display unit is designed and con-

structed to be splashproof, thus it can beinstalled outdoors. You can even hose itdown after a days outing. If it is to beinstalled outdoors, we recommend install-ing it an enclosed cabinet, for maximumprotection against the marine environ-ment.

The temperature and humidity of themounting location should be stable andmoderate. No LCD can provide adequate

contrast if the ambient temperature is tooextreme. The display unit consumes only a mod-

erate amount of power, so there is no needfor forced air ventilation. However, youshould provide adequate space behind andaround the unit to permit circulation ofair and to provide convenient access tothe rear connectors.


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Connections

Connect the signal and power cables, the

ground wire and optional equipment asshown in Figure 5-14.

Figure 5-13 How to mount the display unit

*140(5.51")

10(0.39")

238(9.37")

15(0.59")

15(0.59") *80

(3.15")

*80(3.15")

100

(3.94")

20(0.79")

268(10.55")

130(5.12")

4 - 6

FIXING HOLES

*:SERVICING CLEARANCE

10mm

222(8.7")

236(9.

3")

Cutting size for flushmount

When powering the equipment with 24/32 VDC,replace 10 A fuse in the power cable with5A fuse and attach 5A label (supplied)to fuse holder.

UTION


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33

RP

HDG

NMEA

DJ-1

OPTION

MARINE RADAR

TYPE

SER.NO.

DATECOMPASS SAFE DISTANCE

STD M STEER M

EQUPMENT CLASS

FURUNO ELECTRIC CO., LTD

10.2-31.2VDC

3GND1

2

Signal cable connector

Connect signal cablefrom antenna here.

NMEA connectorConnect navaidnere.

HDG connector

Connect headingsensor nere.

Covered.(not use)

Power cable connectorConnect power

cable here.

Ground terminalConnect ground wire between

here and ship's ground.

OPTION connectorConnect navaid,video sounder, etc.here.

Figure 5-14 Display unit, rear view

ledoM rotcennoC

emaN ataD niP tuO/nI

2M165VCF 1J )5.1(381 4 tuO/nI

185VCF AEMN )5.1(381 4 tuO/nI

285VCF AEMN )5.1(381 4 tuO/nI

192VCF AEMN )0.2/5.1(381 6 tuO/nI

292VCF AEMN )0.2/5.1(381 6 tuO/nI866VCF AEMN )5.1(381 4 tuO/nI

0181PG TUO/NI )0.2/5.1(381 6 tuO/nI

2M0013PG TUO/NI )5.1(381 6 tuO/nI

2M0008PG AEMN )0.2/5.1(381 4 tuO/nI

2M0008SP AEMN )0.2/5.1(381 4 tuO/nI

08PG 1ATAD )0.2/5.1(381 6 tuO/nI

08PG 2ATAD )0.2/5.1(381 6 tuO/nI

2M0081PG TUO/NI )0.2/5.1(381 6 tuO/nI

Note: All plotters in the table except theGP1800M2 can receive TLL data.

Input/Output Data List

CAUTIONTighten the boot-band

securely to ensure

watertightness.

See page39

CAUTIONReplace the fuse to5A for 24/32 VDC set.


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34

SPU-9180

DISPLAYUNIT

J61

VIDEOSOUNDER

Cable suppliedwith radar(connector assy.03-1796(5))

Cable suppliedwith video sounderSolder and

tape.

Figure 5-15 How to connect externalequipment to the OPTION connector

3) Cover signal cable at junction with dis-play unit with silicone sealant.

Distribution NAV data to the otherequipment

This radar can output NAV data receivedfrom a navaid to an echosounder or videoplotter by making the modifications asshown in below.

J55 (NMEA)

SPU9180

TLL, RSD J61

Navaid

Echosounder

Video plotterMODEL 851/861, FMD-811

The position data from navaid can be

used for the echosounder if a video

plotter is not connected.

Procedure

1. Unfasten the nuts fixing the waterproofconnector to remove the covers of thepower and display unit.

2. Remove all connectors from SPU Board(SPU-9180).

3. Unfasten three screws to remove the

board.

4. Remove JP3, R91 and R92 on the partsside of SPU Board.

Navigation aid, video sounderconnection

If your navigation aid can output data inNMEA 0183 data format, your vessels po-sition in latitude and longitude, the range andbearing to waypoint, speed, and course maybe input to this radar, and be seen in the bot-tom text area.

Further, if your video sounder can outputdepth in NMEA 0183 data format, depth canbe displayed on the navigation data dis-played in graph form during stand-by.

You will need an NMEA cable:

For navaid;

Type Code no. RemarksMJ-A6SPF0012-050 000-134-424 6P-6P(5m)MJ-A6SPF0012-100 000-133-817 6P-6P(10m)

For E/S;Type Code no. RemarksMJ-A6SPF0011-050 000-132-224 6P-4P(5m)

MJ-A6SPF0011-100 000-132-336 6P-4P(10m)

Two NMEA connectors are provided at therear of the display unit: the NMEA connec-tor and the OPTION connector.

Heading Sensor Connection

Heading signal can be connected to theHDG connector. 10 m cable assembly isoptionally available.

Type Code no. RemarksMJ-A6SPF0007-100 000-125-237 C-2000MJ-A6SPF0009-100 000-125-236 AD-100

How to use OPTION Connector

To connect external equipment to the OP-TION connector;

1) Remove the plastic cover on the connec-tor.

2) Connect equipment to J61 on the SPUBoard as shown in Figure 5-15.


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35

5. Add jumper wire between J55 pin#3(RXD-H) and J61 pin #1(TXD-H).

6. Add a jumper wire between J55 pin#4(RXD-C) and J61 pin #5(SHIELD).

JP3 JP4CR14

R90R91

R93R94

Q15R95Q16

R92

R91

Add the jumper wire between J61#1 and J55#3.

Add the jumper wire between J61#5 and J55#4.

J61

5

1

4 3

J55R69

C27

R70

7. Connect the NMEA cable to the connec-tor assy (03-1796/5P, supplied with ra-dar) as shown the figure on next page.

8. Connect the 5P connector to J51 on SPUBoard.

9. Replace the covers removed in step 1.

10.Connect navaid and other equipment toradar.

11.Turn on the radar and confirm that NAVdata in properly received at the radar and

external equipment.

5.3 Installation Check List

After completing the installation it is a goodidea to check for proper installation. Followthe checklist below and tick boxes to showproper completion.

Is the signal cable secured against a mastor bulkhead?

Is the cable gland or cable entry on thedeck fully waterproofed?

Are the connections to the battery ofcorrect polarity?

Are all the antenna and display unitsgrounded?

Are all connectors at the rear of the

display unit fastened securely?

JP3 JP4CR14

R90R91

R93R94

Q15R95Q16

R92

R91

Remove R91 and R92.

Remove JP3.

SPU-9180Parts side

NMEA cable

NMEA cableEchosounder

SolderMODEL 851/861, FMD-811

Other Equipment(Telesounder data not be mixed.)


49/57

36

CAUTIONIf it is necessary to open the display unit, be surethe rear cover is fitted to the front chassisproperly when closing the rear cover. Whenreassembling, first turn off the unit and then

press the center of the rear cover to plug in themultipin connector on the rear cover.

5.4 Initial Adjustment ofPicture

Follow the procedure below to obtain properradar picture.

1) Press the [POWER] key on the displayunit. The display should light. Wait untilthe message "ST-BY" appears on thescreen. (About 1:30.)

2) Press [TX ST-BY] key to transmit. Theradar will start transmitting, and you willprobably see some targets around you,even though the radar is not yet properlyadjusted.

3) Select a long range.4) Press the [ECHO] key. The following dis-

play appears.

AUTO 1 2 3MAN

AUTO 1 2 3MAN

GAIN

STC

[

[A/C RAIN 00

FTC 0 1 2

1ECHO KEY

TO EXIT

Currentlevel


Figure 5-16 Display for adjustment ofgain, STC, A/C RAIN and FTC

5) Press the omnipad to select GAIN-AUTO, if it is not already selected.

6) Select minimum range. Press the [ECHO]key and press the omnipad toselect STC-AUTO, if it is not already selected.

5.5 Displaying the InstallationMenus

Two sets of installation menus, InstallationSetup 1 and Installation Setup 2 enable en-try of initial settings and adjustment of theradar.

Procedure

1) Turn on the power while pressing and

holding down the [HM OFF] key.


MAIN MENU

Select item by keysand press ENT key.1. Backlight/Brilliance2. P/L, IR, NR & Radar Mode3. Nav Data4. Mode & Function

5. Tuning AUTO MANUAL6. Self Check7. Installation Setup 1


Figure 5-17 main menu


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37

3) Press the omnipad to select InstallationSetup 1 and press the [ENT] key.

INSTALLATION SETUP 1

Select item and optionby keys.1. Key Beep

2. Hdg Sensor3. Ant on Tx4. Demo Display5. Rotation Speed


OFF ON

MAG GYROROTATE STOPOFF ON

6. Installation Setup 224 48 rpm

Figure 5-18 Installation setup menu 1

4) To display the Installation Setup 2 menu,press the omnipad to select InstallationSetup 2.

INSTALLATION SETUP 2

Select item and optionby trackball.1. Align Heading2. Adjust Sweep Timing3. On Hours 000019.8 H4. Tx Hours 000016.0 H


Figure 5-19 Installation setup 2 menu

5.6 Entering Initial Settings

1) At the Installation Setup 1 menu, pressthe omnipad to select Key Beep. (KeyBeep turns on or off the buzzer whichsounds when a key is pressed.)

2) Press the omnipad to select OFF or ON.

3) Select Hdg Sensor.

4) Select type of heading sensor connectedto the radar; MAGnetic compass orGYRO compass.

5) Press the [ENT] key.

Leave the menu open to complete the nextseveral adjustments.

5.7 Relative BearingAlignment

You have mounted the antenna unit facingstraight ahead in the direction of the bow.Therefore, a small but conspicuous targetdead ahead visually should appear on theheading mark (zero degrees).

In practice, you will probably observe somesmall error on the display because of the dif-ficulty in achieving accurate initial position-ing of the antenna unit. The followingadjustment will compensate for this error,360 degrees.

1) Identify a suitable target (for example,ship or buoy) at a range between 1/8 to 1/4 miles

851 861 operator's manual d 6.26.1998

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