JRC NKE-1125-92 9ft 25kW X-Band Radar Scanner Unit

The JRC NKE-1125-92 is a heavy-duty marine radar scanner unit designed for professional ship-navigation radar systems. It is commonly associated with the JRC JMA-9122-9XA and JMA-7122-9XA 25kW X-band radar configurations.

The scanner contains the transmitter, receiver, modulator, antenna-drive mechanism, encoder, safety switch and other components required to transmit radar pulses and receive returning target echoes.

The photographed equipment is manufactured by Japan Radio Company—JRC. The nameplate identifies it as model NKE-1125-92, Made in Japan.

Product Specifications

Specifications and component compatibility should be verified using the vessel’s radar model, scanner nameplate, motor voltage and existing system drawings.

Compatible JRC Radar Systems

The NKE-1125 family is used across several JRC radar configurations:

The final digit commonly relates to the scanner-motor power arrangement. Before replacement, confirm whether the existing vessel installation uses the correct AC voltage and cable configuration.

Main Scanner Components

Scanner Housing and Pedestal

The weather-resistant housing protects the transmitter, receiver, modulator and antenna-drive mechanism from the marine environment.

Antenna-Drive Motor and Gearbox

The motor and gearbox rotate the slotted-array antenna at the specified speed. Stable rotation is necessary for accurate radar bearing and target presentation.

Encoder

The scanner encoder provides antenna-position information to the radar processor, allowing target echoes to appear at the correct relative bearing.

Safety Switch

The safety switch prevents normal operation while the scanner cover is open. It must never be bypassed during servicing.

Transmitter and Magnetron

The transmitter generates high-power X-band radar pulses. The magnetron is a service component that gradually loses output after extended operating hours.

Modulator Unit

The modulator supplies the high-voltage pulses required by the magnetron. A modulator fault can result in no transmission or transmitter alarms.

How the Scanner Works

The radar processor commands the NKE-1125-92 to begin transmission and antenna rotation. The magnetron generates high-power X-band pulses, which pass through the rotating slotted-array antenna.

When the pulses strike ships, coastlines, buoys or other targets, part of the energy returns to the antenna. The scanner receiver detects these echoes and sends the radar data to the processor and display.

By measuring the time delay and antenna direction, the system calculates the range and bearing of each target.

Typical Marine Applications

• Commercial cargo vessels
• Oil and chemical tankers
• Bulk carriers
• Container ships
• Offshore-support vessels
• Passenger vessels
• Large fishing vessels
• Ocean-going ships
• JMA-9100 and JMA-7100 radar replacement projects

Common Scanner Problems

Scanner Does Not Rotate

Possible causes include a faulty motor, motor driver, brake circuit, gearbox, safety switch, power supply or damaged scanner cable.

Radar Transmits but Shows Weak Echoes

Check the magnetron condition, receiver module, antenna connection, modulator output and radar tuning. A worn magnetron often causes reduced transmission performance.

No Transmission

Inspect the magnetron, modulator, high-voltage section, interlock circuit and scanner communication cable.

Incorrect Target Bearing

A faulty or misaligned encoder can cause target-bearing errors. Radar heading alignment and scanner mounting direction should also be checked.

Abnormal Scanner Noise

Unusual noise may indicate worn bearings, insufficient lubrication, damaged gears or a loose antenna-drive assembly.

Water or Corrosion Inside the Housing

Inspect the scanner-cover gasket, cable glands, drain arrangement and mounting seals. Water ingress can damage the transmitter and motor-control circuits.

Scanner Alarm on the Display

Review the radar alarm code and check scanner communication, motor rotation, safety switch, power input and transmitter status.

Maintenance Recommendations

• Inspect the housing for cracks, corrosion and water ingress.
• Check scanner-cover seals and cable glands.
• Examine motor, bearings and gearbox condition.
• Confirm smooth antenna rotation.
• Inspect the safety switch and interlock mechanism.
• Check encoder alignment and bearing accuracy.
• Monitor magnetron current and transmitting performance.
• Inspect internal connectors and grounding.
• Check the scanner cable for insulation damage.
• Keep the slotted-array radiator clean and unpainted.
• Carry out performance-monitor testing periodically.

The scanner contains lethal high voltage and produces dangerous radio-frequency radiation. Power must be isolated and locked out before opening the unit. Maintenance should only be performed by qualified marine-radar technicians.

Important Note About the Photographed Unit

The supplied photographs show the NKE-1125-92 scanner pedestal with attached cables. The 9ft slotted-array radiator is not shown mounted on the scanner.

Before offering the equipment, confirm:

• Whether the antenna radiator is included
• Motor and power-supply voltage
• Scanner-cable condition
• Magnetron and modulator condition
• Motor rotation and gearbox condition
• Compatibility with the customer’s JMA-9122 or JMA-7122 system

Why Is the NKE-1125-92 Still Required?

Many vessels continue to operate JRC JMA-9100 and JMA-7100 radar systems. Replacing the complete radar may require new displays, processors, cabling, interfaces and class-related work.

A compatible tested NKE-1125-92 scanner can therefore provide a practical replacement solution for a vessel with an existing 9ft 25kW JRC X-band radar installation.

Spare Parts and Replacement Support

Depending on stock, support may be available for:

• Complete NKE-1125-92 scanner
• Scanner housing and pedestal
• Antenna-drive motor
• Gearbox and bearings
• CHT-71A encoder
• CSD-654 safety switch
• Motor-driver circuit
• Brake-control circuit
• Modulator unit
• Magnetron
• Transmitter and receiver modules
• Scanner cable and connectors
• 9ft slotted-array radiator

Frequently Asked Questions

Is the NKE-1125-92 a complete radar?

No. It is the above-deck scanner unit. A complete radar also requires a compatible processor, display, control unit, power supply, cabling and navigation-sensor interfaces.

What is its transmitter output?

It is a 25kW X-band radar scanner.

What antenna size does it use?

The NKE-1125-92 is associated with a 9ft slotted-array antenna.

Which radar model uses this scanner?

It is commonly used with the JRC JMA-9122-9XA and JMA-7122-9XA radar configurations.

Is the antenna radiator included in the photographed product?

The photographs show the scanner pedestal, but the 9ft slotted-array radiator is not attached. Availability should be confirmed separately.

Can the scanner be shipped worldwide?

Yes. Worldwide shipping can be arranged after checking the weight, dimensions, cable condition and included components.

Short Product Description

JRC NKE-1125-92 is a 9ft 25kW X-band marine radar scanner unit used with JMA-9122-9XA and JMA-7122-9XA radar systems. Suitable for replacement, repair and spare-parts requirements on commercial vessels.

Manuals and Related Resources

• JRC JMA-9100/7100 Installation Manual
• JRC NKE-1125 User Manual
• JRC JMA-9122-9XA Technical Information
• Related JRC JMA-9122, JMA-9132 and JMA-9922 Radar

Contact SM MARINE SERVICE™

SM MARINE SERVICE™
Marine Automation & Navigation Equipment Supplier

Available Condition:

• New Equipment
• Used Equipment
• Refurbished Equipment
• Reconditioned Equipment

Stock Location:

• Bangladesh
• China

Services:

• Worldwide Shipping
• Technical Support
• Spare Parts Supply
• Marine Equipment Sourcing

Contact Information

SM MARINE SERVICE™
Samir Market, DT Road, Pahartali, beside CDA Market, Chattogram, Bangladesh

Mobile / WhatsApp / Viber: +88 01818 929292
Email: info@smmarineservice.com
Website: www.smmarineservice.com