JMC NT–2000 - User Manual

Questions and Answers

D
David TuckerAug 23, 2025
What to do if my JMC Receiver receives no messages despite correct settings?
- T
  Thomas SaundersAug 23, 2025
  First, check that the appropriate antenna is correctly plugged into the corresponding rear apron antenna (BNC) connector. Next, run the self-diagnostic tests and verify the receiver test result is “OK.” If it shows “FAILED,” the receiver PCB may be defective, and a qualified technician should check the wiring and replace the PCB if necessary. Ensure that you are within the service area covered by the ground wave of the desired station and check the broadcast schedule of the station. Finally, try replacing the active antenna unit and/or cabling.
J
Jimmy CordovaSep 5, 2025
Why can't I control the screen brightness on my JMC NAVTEX Receiver?
- S
  Sarah HoganSep 6, 2025
  Check to be sure that the power source voltage is within the 11–36V range. If the issue continues, the CPU PCB may be defective. A qualified engineer should check the wiring and replace the PCB if necessary.
J
Joshua MooreSep 4, 2025
Why JMC NT–2000 alarm indications cannot be controlled remotely?
- Z
  Zachary BullockSep 4, 2025
  Ensure that the RS–422 port is enabled (set to ON). Verify that the communications protocol of your application matches that of the RS–422 port. Check that the bit format and baud rate of your application match those of the RS–422 port parameters. Suspect that some of the internal connections to/from the connectors have become loosened or broken, and have a qualified engineer check for faulty wiring harness terminations. Run the self-diagnostic tests and check the results of the RAM and ROM tests.
A
andersonjamesSep 2, 2025
Why JMC Receiver receives no messages with a good antenna and FAILED self-test?
- A
  Alexandra MartinezSep 3, 2025
  This suggests that both receivers have become misaligned. Have a qualified technician check the connections to/from the receiver PCBs and/or replace the PCBs. The CPU PCB may also be defective, or some of its internal connections may be faulty or broken; have a qualified technician check the related wiring and replace the PCB if necessary.
M
Matthew OlsonSep 1, 2025
What to do if JMC NAVTEX Receiver turns on but doesn't respond to key presses?
- S
  Sheena KhanSep 1, 2025
  First, ensure that the power source voltage is within the 11–36V range. Then, reset the system to the factory’s initial settings. If the issue persists, the CPU PCB or the Key PCB may be defective; run the self-diagnostic tests and check the results of the RAM and ROM tests.
C
Cristian JohnstonAug 31, 2025
Why can't my JMC NT–2000 Receiver receive messages in the daytime?
- P
  Patrick BrandtAug 31, 2025
  Verify that you are located within the service area covered by the ground wave of the desired station, which is normally 200 to 400 nautical miles during daytime hours. Also, check the broadcast schedule of the desired station.
J
Jaime CoxAug 29, 2025
Why JMC NT–2000 receives no messages with a good antenna and OK self-test?
- A
  Alexandra EvansAug 29, 2025
  This indicates that the antenna circuit is likely defective. If using an active antenna, replace it with one known to be good. If a correct replacement antenna is unavailable, use approximately 5 meters of insulated wire as a temporary long wire antenna, placing it as high as possible. If the problem persists, have a qualified engineer check the antenna coupler/selector circuit inside the rear apron for faulty or broken connections.
K
kristineperezAug 27, 2025
What to do if JMC NAVTEX Receiver turns on but the screen is blank?
- A
  Alvin OdonnellAug 27, 2025
  Ensure that the power source voltage is within the 11–36V range. Repeatedly press the button to see if the normal brightness returns. The LCD module or the inverter PCB may be defective, so have a qualified technician check the connections and replace the module and/or the PCB. The CPU PCB may also be defective, so have a qualified engineer check the connections and replace the PCB if necessary.
K
Kelly WestAug 27, 2025
Why does my JMC NT–2000 show error characters in messages during the daytime?
- T
  Tasha WallaceAug 27, 2025
  First, verify that you are within the service area covered by the ground wave of the desired station. Run the self-diagnostic tests and check the receiver test results. If the result is “FAILED,” have a qualified technician check the wiring or replace the receiver PCB. Check for any recently installed electronic devices near the receiver or antenna, and if found, turn off or relocate them. Unplug the antenna cable from the BNC connector on the rear apron and check the voltage at the center conductor. The preamplifier in the active antenna unit may be failing, or water may have entered the cable; try replacing the amplifier unit and/or the cable.
C
Chelsea Smith MDAug 25, 2025
Why my JMC NT–2000 Receiver receives no messages even during broadcasting time?
- M
  Maria Macdonald DVMAug 25, 2025
  Check that the antenna cable is correctly plugged into the appropriate rear apron BNC connector receptacle. Also, verify that the connector (BNC) plug is properly installed onto the cable. Try replacing the active antenna. If the issue persists, check the voltage at the center conductor of each antenna connector. It should be 8V+ on the 490 and 518 kHz connectors and 12V+ on the 4209.5 kHz connector. If none of these steps work, have a qualified engineer check the connections to/from the CPU PCB and replace the PCB if needed.

Summary

Typical NAVTEX Message Screen

Introduction to NAVTEX Message Screen

Explains the NAVTEX message screen, on-screen indications, and illustrations.

Receiver Operating Status and Message Identification

Details receiver status indications, operating status line, and message ID format.

Message Screen Indicators and Controls

Describes alarm tags, new message tags, message scrolling, and message text display.

Message Status and Error Rate Information

Explains end-of-message indication, storage status, CER, and prompt line.

New Message Reception and Storage

Details indications for new message reception on first/second receivers and successful storage.

Control Panel Functions

Screen Brightness and Power Control

Explains control of screen brightness (BRT) and power (PWR) functions.

Keypad Dimmer and Audible Monitor

Details keypad backlighting control (DIM) and audible monitoring (MON).

Receiver Display and Alarm Control

Describes switching receiver pages (PAGE) and stopping alarms (STOP ALM).

Navigation and Selection Keys

Explains Up, Left keys for scrolling and menu navigation.

Enter, Down, and Message;Station Selection Keys

Details Enter (ENT) for selection, Down (DOWN) for scrolling, and SEL for station/message lists.

Right Key for Navigation and Management

Explains the Right key for scrolling messages backward or menu navigation.

New Message Key for Acknowledgment

Describes the NEW MSG key for acknowledging new messages and removing the tag.

Message;Station Rejection Key

Details the REJ key to display lists of rejected stations and message types.

Menu Key for System Configuration

Explains the MENU key to open the SYSTEM MENU for customization and settings.

Store and Clear Message Keys

Describes STO MSG to protect messages and CLR to remove tags/close menus.

Basic Operating Procedure

Introduction to Basic Operation

Provides an overview of basic operation without prior knowledge of NAVTEX.

Turning the Equipment On;Off

Details the procedure for turning the equipment on and off using the PWR key.

Adjusting Screen and Keypad Brightness

Explains how to adjust screen (BRT) and keypad (DIM) brightness levels.

Switching First and Second Receivers

Explains how to switch between the first (518 kHz) and second (490/4209.5 kHz) receiver displays.

Scrolling NAVTEX Messages

Describes line-by-line and message-by-message scrolling using arrow keys.

Stopping Audible and Visual Alarm

Explains how to silence audible alarms and remove visual alarm tags using the STOP ALM key.

Protecting Messages for Permanent Storage

Details the procedure to protect specific messages from automatic erasure using the STO MSG key.

Removing Protection Tag

Explains the steps to remove the protection tag from a stored message.

Customizing Operation via Menu System

Introduction and Menu Access

Explains menu system access and basic customization options.

Display Settings

Covers background colors, font types, and screen sleep mode settings.

Setting Screen Sleep Times

Explains how to set times for automatic reduction of screen brightness.

Receiver and Beep Settings

Covers selecting second receiver frequencies and turning keypress beep on/off.

Message Filtering Configuration

Details selecting/rejecting transmitters and message types.

Stored Message Search

Explains how to search stored messages by station ID or message type.

Output Configuration

Covers selecting and outputting various NAVTEX messages.

Output Port Configuration

Details setting output ports, protocols, bit formats, and data transfer rates.

System Diagnostics

Explains performing self-diagnostic tests and checking their results.

Message Alarms and System Reset

Covers turning message alarms on/off and resetting the system to factory defaults.

User-Level Troubleshooting

Introduction to Troubleshooting

Provides an overview of common troubles and recommended remedies.

Power-Up Problems

Lists symptoms and solutions for issues related to turning the equipment on.

No Message Reception Issues

Lists symptoms and solutions for problems with receiving NAVTEX messages.

Message Storage Problems

Lists symptoms and solutions for issues with message storage and memory.

Poor Reception Issues

Lists symptoms and solutions for poor reception with many error characters.

Screen and Brightness Issues

Addresses blank screens and uncontrollable screen brightness.

Keypress and Alarm Issues

Troubleshoots no keypress beep and no message alarm indication.

Response and Output Issues

Addresses no response from keypress and no message alarm output.

External Output and Control Problems

Troubleshoots no external outputs and external control problems.

User-Level Maintenance Instructions

Maintenance on Equipment Cabinet

Provides instructions for cleaning the cabinet surface and filter.

Maintenance on Electrical Connections

Details annual maintenance for electrical contacts to prevent corrosion.

Maintenance on Active Antenna Unit

Outlines maintenance procedures for the antenna unit, including whip, housing, and cabling.

Recommended Spare Parts

Lists recommended spare parts for maintenance and servicing.

Installation

Receiver Cabinet Installation

Covers general precautions and requirements for installing the receiver cabinet.

Mounting the Receiver Cabinet

Details the procedure for mounting the receiver cabinet using a tabletop bracket.

Antenna Installation

Covers installation site requirements for active and long wire antennas.

Precautions for Cabling

Provides precautions for routing cables to minimize interference and ensure safety.

Electrical Connections

Introduces making electrical connections via rear panel connectors and terminals.

Connector Pin Assignments and Connections

Details pin assignments for power supply, ground terminal, and other connectors.

INS Port Data and Command Sentences

Explains data sentence formats for INS/IBS system communications via RS-422.

NAVTEX Receiver Masks

Explains commands to manipulate configuration masks for message reception.

Alarm Output Sentence Format

Details the format of sentences output for reporting alarms or malfunctions.

Alarm Acknowledgement

Explains commands to externally acknowledge or stop current message alarms.

Proprietary Sentences

Lists proprietary commands for externally switching the second receiver frequency.

Summarized Theory of Operation

What is NAVTEX?

Provides a basic explanation of the NAVTEX system and its purpose.

NAVTEX Operating Frequencies and Service Area

Lists allocated frequencies and explains typical coverage areas for NAVTEX stations.

NAVTEX Error Correction

Describes methods used for error correction in NAVTEX transmissions to ensure reliable reception.

NAVTEX Receiver - General Overview

Provides a general overview of NAVTEX receiver functions and compliance with regulations.

NT-2000;DEBEG 2902 NAVTEX Receiver Features

Describes the specific features and capabilities of the NT-2000/DEBEG 2902 receiver.

Operating Principle of NT-2000;DEBEG 2902

Explains the operating principle, including PCB interconnections and receiver circuits.

Specifications

Equipment Category and Receiver Frequencies

Specifies equipment categories and supported receive frequencies.

Receiver Type, Antenna Inputs, and Protection

Details receiver types, antenna input specifications, and input protection.

Active Antennas and Receiver Sensitivity

Describes active antennas and minimum values for message reception sensitivity.

Demodulator and Reception Modes

Specifies demodulator type and details single and dual frequency reception modes.

Second Receiver Selection and Display Specs

Covers second receiver selection, time source, display resolution, and UI language.

Text Display, Message Handling, and Storage

Details text display format, message reception/storage indications, and scrolling.

Message Storage Capacity and Protection

Details message capacity, duration, protection, and storage without power.

Message ID Storage and Output Options

Specifies message ID storage capacity and options for stored message outputs.

External I;O Interfaces and Alarm Specifications

Lists external interfaces and details message alarm specifications.

Power, Cabinet, and Environmental Specifications

Covers power requirements, cabinet dimensions, safe distances, and ambient temperatures.

Compliances and Specifications Disclaimer

Lists relevant IMO and IEC standards and a disclaimer on specification changes.

List of Alarms

Message Alarms

Details alarms for D-Type and A, B, L-Type messages, including conditions and interface.

Operational Alarms

Lists operational alarms like Storage Limit, Memory-Full, and Invalid Keypress.

List of Abbreviations

User Settings To Be Stored in Non-Volatile Memory

Screen and Keypad Brightness Levels

Indicates that the last used screen and keypad brightness levels are stored.

Menu System Settings and Defaults

Lists settings configurable via the menu system, including display, frequency, beep, and alarms.

Station and Message Type Selection;Rejection

Details user settings for selecting or rejecting stations and message types.

Output Port Settings and Message Output

Covers settings for output ports and configuration for printing live messages.

List of Components To Be Shipped

JMC NT–2000 Specifications

General

Brand	JMC
Model	NT–2000
Category	Receiver
Language	English

Related product manuals

JMC DEBEG 2902

102 pages