Furuno FR-8051 manual Tuning the Receiver, Adjusting Sensitivity, Adjusting Picture Brilliance

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1.6 Tuning the Receiver

The receiver can be tuned automatically or manu- ally. The default (factory setting) is automatic tun- ing.

Selecting tuning mode

1)Press the MENU key.

2)Select the INITIAL menu.

3)Press the ENTER/SELECT key.

Note: The above three steps can also be done by pressing and holding down the MENU key.

4)Select TUNE SET and press the ENTER/SE- LECT key.

5)Select AUTO (or MANUal).

6)Press the ENTER/SELECT key.

7)Press the MENU key.

Manual tuning

1)Select manual tuning by following "selecting tuning mode."

2)While pressing and holding down the HM OFF switch, adjust the trackball to display the long- est tuning indicator.

Tuning indicator

MANUAL

Video lockup recovery

Video lockup or picture freeze, can occur unex- pectedly on digital rasterscan radars. This is mainly caused by heavy spike noise in the power line, and can be noticed by carefully watching the nearly invisible sweep line. If you suspect that the picture is not updated every scan of the antenna or no key entry is accepted notwithstanding the apparently normal picture, turn the power off and on.

1.7 Adjusting Sensitivity

The GAIN control adjusts the sensitivity of the receiver and thus the intensity of echoes as they appear on the screen.

The proper setting is such that the background noise is just visible on the screen. If you set up for too little sensitivity, weak echoes may be missed. On the other hand excessive sensitivity yields too much background noise; strong targets may be missed because of the poor contrast be- tween desired echoes and the background noise on the display.

To adjust receiver sensitivity, transmit on long range, and adjust the GAIN control so background noise is just visible on the screen.

1.8 Adjusting Picture Brilliance

The BRILL control adjusts the brilliance of the picture.

Figure 1-7 Display appearance when

manual tuning is in effect

Note: The receiver may be detuned if your radar is hit by another radar in vicinity. To retune in automatic tuning, press the ST BY/TX key twice.

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Contents Marine Radar First Edition NOV Safety Information Do not diassemble or modify the equipment Iii Radio Frequency Radation HazardUse the correct fuse Table of Contents Maintenance Foreword Features Word to FR-8051/8111/8251 OwnersVii Configuration of FR-8051/8111/8251 Antenna Unit SpecificationsTransceiver Module Display Unit Power Supply and Power ConsumptionEnvironmental Conditions OthersStandard Set Equipment ListsXii Name Type Qty RemarksSpare Parts Optional EquipmentXiii Name Type Code No RemarksXiv Categorization by SpecificationFunction Type Control Description Operation25 NM Display IndicationsDisplay indications lower part Selecting Range Turning the Radar On/OffTransmitting, Stand-by Selecting presentation mode Presentation ModePresentation mode Description Representative display Description Presentation modeBasic menu operation Menu OverviewChanging pages on the Initial menu MK Erase erase all fixed marks Menu treeInitial Tune SET AUTO, Manu SPD Mode MAN, LOG, NAV Adjusting Sensitivity Tuning the ReceiverAdjusting Picture Brilliance Selecting tuning modeAdjusting Range Ring Brilliance Adjusting Brilliance of Control Panel and MarkersSuppressing Sea Clutter Automatic anti-clutter controlHeading and North Markers Suppressing Rain ClutterMeasuring the Range Measuring range by the range ringsMeasuring Bearing Collision Assessment by Measuring Range Offset EBL Canceling the cursor offsetOff-centering the Picture Index LinesInscribing Marks on the Display ZoomFunction key Turning on a function Own Ship SpeedAutomatic speed input Interference Rejector Ship’s GraphicEcho Trails Manual speed inputStarting echo trail Canceling echo trailTrail time Trail referenceTrail brilliance Electronic Plotting E-plotPlotting a target Target data Canceling target plottingTrue or relative vector Vector timeSetting a guard zone Setting a Guard Alarm ZoneSelecting guard zone type Activating the guard zonesSilencing the aural alarm Watch AlarmCanceling the guard zone and guard alarm How to turn on echo averaging26 Echo average Suppressing Second-Trace EchoesEcho Stretch Presetting pulselengthNoise Rejection Selecting PulselengthOutputting Cursor Position TLL data Waypoint DisplaySelecting pulselength set to use Selecting Unit of Range Measurement, Bearing Reference Alarm Output Signal On/OffSector Blanking Radar Observation Range ResolutionRadar Picture, Target Properties and Radar Pulse False Echoes Bearing ResolutionIndirect echoes Multiple echoesSide-lobe echoes Minimum and Maximum RangesMinimum range Blind and shadow sectorsLocating a Ship or Survival Craft in Distress by Sart Gain When Working on the Antenna Unit MaintenancePart Type Life expectancy Remarks Interval Check point Check and measures RemarksSimple Troubleshooting TroubleshootingProblem Remedy Serviceman qualification Advanced-level TroubleshootingProblem Check point and probable Remedy Cause Problem Check point and probable Remedy Cause Problem Check point and probable Remedy Cause Diagnostic test, test pattern Diagnostic TestAntenna Unit Location of PartsModulator Trigger RF Transceiver UnitRF transceiver unit FR-8051/8111 Display unit, top view Display Unit common to all modelsDisplay unit, right side view Operating a performance monitor Performance MonitorTransmitter Receiver Performance Display Meaning Transmitter normal Receiver normalVideo Plotter RP-15 Auto Plotter ARP-15Fluxgate Heading Sensor C-2000 Page