Guidelines for Assessment of Ship Navigation Radar Setup, Maintenance and Repair

Hands-on Assessment Question Bank - ETO Professional Skills Calibration

I. Brief description of contents

(i) Assessment tasks and implementation

Way:Use a real radar or simulator.
Scene:The radar is normally powered on and connected to the GNSS, compass, and rangefinder signals.
Program:Candidates identify components, perform and explain self-tests, and are judged by an assessor setting up simple faults.
Time:No more than 15 minutes.

(ii) Elements and criteria for assessment

1. Identification and functioning of the main components of the radar.
2. Measurement of basic circuit parameters (safety measures, magnetron current, tuning indication).
3. Self-test operation and interpretation of key indicators (I/O interfaces, VDR verification).
4. Ranging and orientation error analysis and correction.
5. System fault judgment, alarm elimination and emergency response.

II. Operating Methods (Furuno FAR-28×7 as an example)

:: (i) Identification of major components of radar equipment (key elements)

Correct identification of components: includingMagnetron, Waveguide/Coaxial Cable, Receiver Module, Antenna, Transceiver (with Modulator), Mainframe (with Motherboard, Power Supply, Interface), Keyboard & Trackball, Monitoretc.

◎ (ii) Measurement of basic radar circuit parameters (general elements)

1. Security measures:Wear insulated gloves, goggles, helmet and anti-static clothing; strictly prohibit carrying magnetic items; ensure that tools are insulated and the environment is dry and ventilated.

2. Receiver module status judgment (tuning indication):

Step 1: Select the 48 n mile range.
Step 2: Select Manual Tuning Mode.
Step 3: Observe the TUNE tuning bar.
Step 4: Tune the voltage from minimum to maximum, the indication should be presentedFrom small to large and back again.and more than two significantly large values.

3. Transmitter operating status determination (magnetron current):Start the self-test to see MAG CURRENT values and compare them with the instruction manual reference values.

:: (iii) Radar self-testing operations (key elements)

1. Operational processes:MENU → 9[CUSTOMIZE TEST] → 8[TEST] → 2[SELF TEST] → 2[START].

2. Meaning of key indicators:ROM/RAM status, processor voltage, motor voltage, RF unit temperature, tuning status, magnetron current, trigger frequency, antenna speed, and so on.

3. Sensor access:Manually access GNSS, compass, and rangefinder signals and verify VDR video signal output.

◎ (iv) Radar error calibration (general elements)

1. Analysis of causes:Systematic or random errors are determined by image deformation, error size, and sea environment.
2. Calibration process:Determine the error value by GPS or single object marker → Go to the initialization menu → Adjust the distance/bearing error value.

:: (v) Radar system fault determination methods (key elements)

1. Alarm abatement:Analyze the fault codes using the ACK Key muffled, report the driver's seat as appropriate.
2. Emergency response:Determine whether it is external interference or equipment failure; check the power supply and cables if it does not start; try to reboot or self-test; if ineffective immediately activate the backup radar.

3. Fault point localization and handling:

Use the VRM, EBL, and HL tools to check for correct return position.
Adjust the range, gain, tuning and other controls and observe the screen response to narrow down the fault.
Security Red Line:Disconnect and discharge the transmitter for maintenance; set the safety switch to “OFF” and fasten the safety rope for maintenance of the antenna.
Proficient in the use of multimeters (voltage/current) and megohmmeters (insulation resistance).

4. Recovery:Restore the disassembled parts, turn on the power and adjust the image to the best condition.

Radar Evaluation Pocket Guide (ETO Pocket Guide)

1. Critical operating path (Furuno FAR-28×7)

sports event	Menu/key path	Judgment/Action
priming self-test	MENU → 9 → 8 → 2 [SELF TEST].	Confirm that the display is OK and press F1 to close
Initialization menu	Hold down [5:HL OFF] + Tap [1:HL OFF]	Calibration Distance (Timing) and Headers (HD)
Performance Monitoring	MENU → [PERFORMANCE MONITOR]	Range 24NM, observe characteristic arcs

2. Criteria for core parameters (basis for determination)

Magnetron current. X-band 5-12A / S-band 6-10A
Tuning Voltage. The sweeping process shall occur 2 or more maximum value
Equipment temperature. -40°C to +70°C
IF Frequency. 55 to 65 MHz (60 MHz typical)
方位精度: The error must be controlled within ±0.5° less than

3. Preliminary Determination of Common Failures

No image. Check Standby Status / Check Magnetron Current
Echo Blur. Adjusting Tune / Checking for Wave Tube Fluid
Cursor jumps. Cleaning Trackball (Isopropyl Alcohol Swabs)
Breakwater bends. Adjusting TIMING ADJ.

⚠️ Safety Red Line (Three Principles of ETO Maintenance)

1. Power failure discharges. The modulator must be physically disconnected and the high voltage capacitors discharged before servicing.

2. Antenna lockout. Before servicing the antenna, turn the safety switch OFF and hang a warning sign.

3. Insulation and antimagnetic. Magnetic objects are strictly prohibited and insulated protective equipment must be worn.

Note: This table is for evaluation sprint reference only, please follow the real boat equipment manual for detailed parameters.

Radar Failure Response Logic Mind Map

Fault occurs → Alarm processing → Quick diagnosis → Emergency recovery

1. Alarm intervention

Action:press a button [ACK] Key muffling and flashing → Record Alarm Code → Report to the officer on duty at the bridge.

↓

2. Preliminary screening

Physical Examination:

Check power switch and fuse
Observe antenna rotation and noise
Check waveguide/cable seals

Image check:

Adjusting Gain and Tune Indications
Switching range to check pulse width
Confirm Standby status

↓

3. In-depth diagnosis

Core Tools:activate (a plan) Diagnostic Test Check magnetron current (5-12A) and temperature → On Performance Monitor (PM) Evaluate transceiver performance (24 NM arcs).

↓

4. Addressing decision-making

Interim recovery:

Reboot the system to save the flash memory
Clean trackball/replace fuse
Enable backup radar/primary and secondary switching

Professional Repair:

Magnetron aging (abnormal current)
PCB failure (self-test display NG)
Report agent, provide equipment model

⚠ Principles of emergency response:Safety first, outside first, inside first, simplify first, ensure backup.

Furuno Radar Core Spare Parts List

Maintenance standards for magnetrons, fuses, batteries and wearing parts

I. Core Emission Unit: Magnetron

Radar model/band	Common specifications	rating	Theoretical life (reference)
X-Band (12.5 kW)	MAF-1565N	12.5 kW	20,000 Hours
X-Band (25 kW)	MG5436 / MG5223F	25 kW	4,000 - 8,000 Hours
S-Band (30 kW)	MG5241 / MAF-1562V	30 kW	4,000 Hours

Replacement Tip: Actual life depends on firing hours and warm-up habits. After replacement, it must be reset in the service menu TX TIME And “seasoned” operations.

Circuit Protection: Common Fuses (Fuse)

Fuses are located at the rear of the Processor Unit (RPU) and on the monitor power supply board, and must not be replaced with non-compliant spare parts.

AC power supply circuit (100-230V).

RPU Processor Unit. 10A / 15A (250V)
MU Monitor Unit. 3A / 5A (250V)

DC power supply circuit (24V).

RPU Processor Unit. 20A (125V)
Antenna motor power supply. 5A / 7A (125V)

III. Data retention: rosette circuit board batteries

Spare part model: CR2450 / CR2032 (depending on specific PCB version)

Replacement cycle: suggestion Every 5 years Replace once.

Signs: After power failure, the data is lost and the self-test shows “NG”.

IV. Mechanical consumables and chemicals

Antenna Drive Belt: Check tightness (annually).
Antifreeze lubricant: For gearing (depending on ambient temperature).
Isopropyl Alcohol. For cleaning trackballs and rollers.
Silica gel desiccant: Place in the transceiver case to protect it from moisture.
Watertight seals: Antenna cover and junction box replaced after repair.

Note: Power must be disconnected before replacing any part and the antenna safety switch status must be verified before turning on the transceiver.