Furuno FR-1710 manual Advanced-level troubleshooting, Problem Check point Remedy Probable cause

Page 60

Table 3-6 Advanced-level troubleshooting

Problem

Check point and

Remedy

 

probable cause

 

 

 

 

 

Adjust GAIN control with A/C

1. IF amplifier

1. Replace IF amplifier.

SEA control set at minimum.

2.

Signal cable between

2.

Check continuity and isolation of

Marks and legends appear

 

antenna and display

 

coaxial cable. (Note: Disconnect

but no noise or echo.

 

 

 

the plug and lugs at both ends of

 

 

 

 

coaxial cable before checking it

 

 

 

 

by ohmmeter.)

 

3.

Video Amplifier Board

3.

Check video coax line for secure

 

 

 

 

connection. If connection is good,

 

 

 

 

replace SPU Board.

 

 

 

Marks, legends and noise

1. Magnetron

1. Check magnetron current.

appear but no echo.

2.

Modulator Board

2.

Replace Modulator Board.

(Transmission leak,

3.

SPU Board

3.

Replace SPU Board.

representing own ship

 

 

 

 

position, is absent.)

 

 

 

 

 

 

 

Picture not updated

1. Bearing Signal Generator

1. Check the connection of signal

 

 

Board (scanner unit)

 

cable.

 

2.

SPU Board

2.

Replace SPU Board.

 

3.

Video lockup

3.

Turn off and on radar.

 

 

 

Incorrect orientation of

1. SPU Board

1. The message "HD SIG

picture

 

 

 

MISSING" appears when the

 

 

 

 

heading pulse is not received

 

 

 

 

during stand-by.

 

2.

Gyro Interface

2.

Replace gyro interface.

 

 

 

Tuning manually adjusted

1. Deteriorated magnetron

1. With radar transmitting on 48 nm

but poor sensitivity

 

 

 

range, check magnetron

 

 

 

 

current. If current is below normal

 

 

 

 

value, magnetron may be

 

 

 

 

defective. Replace magnetron.

 

2.

Detuned MIC

2.

Check MIC detecting current. If it

 

 

 

 

is below normal value, MIC may

 

 

 

 

have become detuned. MIC must

 

 

 

 

be tuned.

 

3.

Dirt on radiator face

3.

Clean radiator surface.

 

4.

Second trace rejection is

4.

Disable the second-trace rejector

 

 

ON.

 

referring to paragraph 1.33.

 

 

 

Range changed but radar

1. Defective RANGE key

1. Try to hit [+] and [-] RANGE

picture does not change

 

 

 

keys several times. If unsuccess-

 

 

 

 

ful, replacement of keypad may

 

 

 

 

be required.

 

2.

SPU Board

2.

Replace SPU Board.

 

3.

Mother Board

3.

Replace Mother Board.

 

4.

Video lockup

4.

Turn off and on radar.

 

 

 

 

 

3-5

Image 60
Contents Marine Radar First Edition NOV Do not operate the equipment with wet hands Keep heater away from equipmentDo not open the equipment Do not disassemble or modify the equipmentUse the proper fuse Table of Contents SP-1 Declaration of Conformity FR-1760DSFeatures IntroductionWord to the Owner of This Furuno Radar System Configuration FR-1760DSFR-1710/1725 Antenna Unit Display UnitMenu Tree ViiiPlot Menu Mark Disp OFF Erase VEC REF REL True VEC Time Curs RNG INT REJ OFF Stretch Enhance Contrast Auto Xii Turning on the Power Operational OverviewTransmitter on Control Description Control descriptionTuning the Receiver CRT BrillianceControl Panel Backlighting Degaussing the Screen Initializing the Compass ReadoutOn-screen Legends and Markers On-screen legends and markersSelecting presentation mode Presentation ModesCourse-up Mode Selecting the Range Scale Screen showsEntering Own Ship’s Speed Automatic speed inputManual speed input Pulselength, Echo Stretch 10 Echo stretchS1P Adjusting the Sensitivity Manual adjustment by the A/C SEA controlAutomatic adjustment by the A/C Auto control Suppressing Sea ClutterSuppressing Precipitation Clutter Interference RejectorMeasuring the Range Measuring BearingMeasuring range by the fixed range rings Measuring range by the variable range marker VRMCollision Assessment by the Offset EBL Measuring Range and Bearing Between Two TargetsSetting a Target Alarm Zone 18 Measuring range and bearing Between two targetsAcknowledging alarm Deactivating target alarm zoneInward and outward alarms Off-centering shiftEcho Averaging 23 Echo SIG menuElectronic Plotting Aid EPA Plotting a targetTrue or relative vector, vector time Target dataTerminating target plotting Reading the target dataSetting CPA/TCPA alarm ranges Silencing CPA/TCPA audible alarmLost target alarm CPA/TCPA AlarmTarget Trails Echo Trails Past plot pointsTrue or relative trails Trail gradation Selecting trail timeRestoring trails Displaying, erasing target trailsResetting target trails Trail brillianceThin trails Trail afterglowParallel Index Lines Origin MarkZoom MarkersPresetting the user keys Presetting the function keysUser Keys F1, F2, F3 Function KeysFunc key objectives 42 FUNC1 menuAdjusting Brilliance of Screen Data Suppressing Second-trace EchoesTime Alarm Noise RejectorEnhanced Video Degaussing Interval Navigation DataVideo Contrast Clutter SweepOutputting Target Position Background Color Selecting Range ScalesSelecting Bearing Scale Format Available color combinations46 A/D Converter Curve Setting A/D curve settingsEnlarging Close-in Targets Alarms AlarmsAlarms con’t Peformance MonitorRadar resolution Radar ObservationGeneral Minimum and maximum rangesFalse Echoes Bearing accuracyRange measurement Multiple echoesSart Search and Rescue Transponder Virtual imageShadow sectors Sart range errors Showing Sart marks on the radar displayGeneral remarks on receiving Sart Radar bandwidthRacon Radar Beacon Radar side lobesGain SEA controlMAINTENANCE, Troubleshooting Periodic Maintenance ScheduleMaintenance schedule On nextMaintenance schedule con’t Life Expectancy of Major PartsLife expectancy of major parts Fuse Replacement Simple Troubleshooting Replacement of BatteriesBattery replacement information Easy troubleshootingAdvanced-level Troubleshooting Serviceman qualificationService call Advanced-level troubleshooting Problem Check point Remedy Probable causeAdvanced-level troubleshooting con’t Diagnostic Test Sequence for diagnostic testTest results screen Display circuit test Parts Location Left side viewDisplay unit, top view FR-1760DS Scanner Unit Scanner unit, left side viewFR-1760DS Scanner Unit con’t Scanner unit, right side view, RF section removedFR-1760DS Power Supply Unit FR-1760DS Power supply unitFR-1710/1725 Scanner Unit RF module Upper partModule Lower part Specifications of Marine Radar Radar Display Dimension and Mass Coating Color Index RaconIndex-2