GMDSS Operator/Maintainer License (DB)

The DB confers the operating authority of the DO and the DM (and, by extension, it also confers the operating authority of the PG and MP).

The DO qualifies the holder to operate, and make some basic equipment adjustments to, Global Maritime Distress and Safety System (GMDSS) radio installations. It also confers the operating authority of the MP.

The DM qualifies personnel as GMDSS radio maintainers to perform at sea repair and maintenance of GMDSS equipment. It also confers the operating authority of the PG and MP.

A PG is required to adjust, maintain, or internally repair FCC licensed radiotelephone transmitters in the aviation, maritime, and international fixed public radio services. It conveys all of the operating authority of the MP. It is also required to operate any compulsorily equipped ship radiotelephone station operating with more than 1500 watts of peak envelope power or voluntarily equipped ship and aeronautical (including aircraft) stations with more than 1000 watts of peak envelope power.

A MP is required to operate radiotelephone stations aboard certain vessels that sail the Great Lakes. They are also required to operate radiotelephone stations aboard vessels of more than 300 gross tons and vessels which carry more than six passengers for hire in the open sea or any tidewater area of the United States. They are also required to operate certain aviation radiotelephone stations and certain coast radiotelephone stations.

The testing elements for this license includes Element 1, Element 3, Element 7, and Element 9

Element 1 - Basic radio law and operating practice with which every maritime radio operator should be familiar. To pass, an examinee must correctly answer at least 18 out of 24 questions.

Element 3 - General Radiotelephone. Electronic fundamentals and techniques required to adjust, repair, and maintain radio transmitters and receivers. The exam consists of questions from the following categories: operating procedures, radio wave propagation, radio practice, electrical principles, circuit components, practical circuits, signals and emissions, and antennas and feed lines. To pass, an examinee must correctly answer at least 57 out of 76 questions.

Element 7 - GMDSS Radio Operating Practices. GMDSS radio operating procedures and practices sufficient to show detailed practical knowledge of the operation of all GMDSS sub-systems and equipment. The exam consists of questions from the following categories: general information, narrow band direct printing, INMARSAT, NAVTEX, digital selective calling, and survival craft. To pass, an examinee must correctly answer at least 75 out of 100 questions.

Element 9 - GMDSS Radio Maintenance Practices and Procedures. Requirements set forth in IMO Assembly on Training for Radio Personnel (GMDSS), Annex 5 and IMO Assembly on Radio Maintenance Guidelines for the Global Maritime Distress and Safety System related to Sea Areas A3 and A4. The exam consists of questions from the following categories: radio system theory, amplifiers, power sources, troubleshooting, digital theory, and GMDSS equipment and regulations. To pass, an examinee must correctly answer at least 38 out of 50 questions.

The GMDSS Maintainers License test consists of the exams for element 1, element 3, and element 9.

For more information concerning the GMDSS Maintainers License,visit the FCC Website's DB License Page

 If you desire the Radar Endorsement for this license, you must complete the element 8 exam.

Element 8 - Ship Radar Techniques. Specialized theory and practice applicable to the proper installation, servicing, and maintenance of ship radar equipment in general use for marine navigation purposes. To pass, an examinee must correctly answer at least 38 out of 50 questions.

If you need more information about the Ship Radar Endorsement, visit the FCC's webpage

Failure to prepare is preparing to fail.
-----John Wooden, Legendary
UCLA Basketball Coach

Only subscribers have access to these tests.

Untitled 1

Element 1

Element 1 Practice Test 1 Element 1 Practice Test 2
Element 1 Practice Test 3 Element 1 Practice Test 4
Element 1 Practice Test 5 Element 1 Practice Test 6

Element 1 Topic Tests - Random Ordered Questions

Topic A: Rules and Regulation Practice Test
- 36 questions covering these topics:

    Equipment Requirements
    License Requirements
    Watchkeeping
    Logkeeping
    Log Entries
    Miscellaneous Rules and Regulations
Topic B: Communications Procedures Practice Test
- 36 questions covering these topics:

    Bridge-to-Bridge Operations
    Operating Procedures
    Distress Communications
    Urgency and Safety Communications
    GMDSS
Topic C: Equipment Operations Practice Test
- 36 questions covering these topics:

    VHF Equipment Controls
    VHF Channel Selection
    MF-HF Equipment Controls
    MF-HF Frequency & Emission Selection
    Equipment Tests
    Equipment Faults
Topic D: Other equipment Practice Test
-36 questions covering these topics:

    Antennas
    Power Sources
    EPIRBS
    SARTS
    Survival Craft VHF
    NAVTEX

Untitled 1

Element 3

Element 3 Practice Test 1 Element 3 Practice Test 2
Element 3 Practice Test 3 Element 3 Practice Test 4
Element 3 Practice Test 5 Element 3 Practice Test 6

Element 3 Topic Tests - Random Ordered Questions

Topic A:  Principles Practice Test
-
 48 questions covering these topics:

    Electrical Elements
    Magnetism
    Materials
    Resistance, Capacitance & Inductance
    Semi-conductors
    Electrical Measurements
    Waveforms
    Conduction
Topic B: Electrical Math Practice Test
-
  60 questions covering these topics:

    Ohm’s Law
    Frequency
    Waveforms
    Power Relationships
    RC Time Constants
    Impedance Networks
    Calculations
Topic C: Components Practice Test
-
  60 questions covering these topics:

    Photoconductive Devices
    Capacitors
    Transformers
    Voltage Regulators, Zener Diodes
    SCRs, Triacs
    Diodes
    Transistors
    Light Emitting Diodes
    Devices
Topic D: CircuitsPractice Test
24 questions covering these topics:

    R-L-C Circuits
    Op Amps
    Phase Locked Loops (PLLs);  and
    Voltage Controlled Oscillators (VCOs); Mixers
    Schematics
Topic E: Digital Logic Practice Test
48 questions covering these topics:
 
    Types of Logic
    Logic Gates
    Logic Levels
    Flip-Flops
    Multivibrators
    Memory
    Microprocessors
    Counters, Dividers, Converters
Topic F: Receivers Practice Test
60 questions covering these topics:

    Receiver Theory
    RF Amplifiers
    Oscillators
    Mixers
    IF Amplifiers
    Filters and IF Amplifiers
    Filters
    Detectors
    Audio & Squelch Circuits
    Receiver Performance
Topic G: Transmitters Practice Test
36 questions covering these topics:

    Amplifiers - 1
    Amplifiers - 2
    Oscillators & Modulators
    Resonance - Tuning Networks
    SSB Transmitters
    Technology
Topic H: Modulation Practice Test
18 questions covering these topics:

    Frequency Modulation
    SSB Modulation
    Pulse Modulation
Topic I: Power Sources Practice Test
12 questions covering these topics:

    Batteries
    Motors & Generators
Topic J: Antennas Practice Test
30 questions covering these topics:

    Antenna Theory
    Voltage, Current and Power Relationships
    Frequency and Bandwidth
    Transmission Lines
    Effective Radiated Power
Topic K: Aircraft Practice Test
36 questions covering these topics:

    Distance Measuring Equipment
    VHF Omnidirectional Range (VOR)
    Instrument Landing System (ILS)
    Automatic Direction Finding Equipment (ADF) and Transponders
    Aircraft Antenna Systems and Frequencies
    Equipment Functions
Topic L: Installation, Maintenance & Repair Practice Test
-
 48 questions covering these topics:

    Indicating Meters
    Test Equipment
    Oscilloscopes
    Specialized Instruments
    Measurement Procedures
    Repair Procedures
    Installation Codes & Procedures
    Troubleshooting
Topic M: Communications TechnologyPractice Test
-
 18 questions covering these topics:

    Types of Transmissions
    Coding and Multiplexing
    Signal Processing, Software and Codes
Topic N: Marine Practice Test
30 questions covering these topics:

    VHF
    MF-HF, SSB-SITOR
    Survival Craft Equipment: VHF, SARTs & EPIRBs
    FAX, NAVTEX
    NMEA Data
Topic O: Radar Practice Test
30 questions covering these topics:

    RADAR Theory
    Components
    Range, Pulse Width & Repetition Rate
    Antennas & Waveguides
    RADAR Equipment
Topic P: Satellite Practice Test
24 questions covering these topics:

    Low Earth Orbit Systems
    INMARSAT Communications Systems-1
    INMARSAT Communications Systems-2
    GPS
Topic Q: Safety Practice Test
12 questions covering these topics:

    Radiation Exposure
    Safety Steps

Untitled 1

Element 7

Element 7 Practice Test 1 Element 7 Practice Test 2
Element 7 Practice Test 3 Element 7 Practice Test 4
Element 7 Practice Test 5 Element 7 Practice Test 6

Element 7 Topic Tests - Random Ordered Questions

Topic A: General Information and System Overview Practice Test
-  36 questions covering these topics:

    Fundamental Concepts
    Equipment Systems
    Sea Areas
    Functional Requirements
    Carriage Requirements
& nbsp;   Maintenance Options
Topic B:  Principles of Communications Practice Test
-  36 questions covering these topics:

    Radio Spectrum
    Frequency Bands
    Modulation, Demodulation, AM, FM
    Carrier and Sidebands
    Channel Spacing
    Antennas
Topic C:  F.C.C. Rules & Regulations Practice Test
-  48 questions covering these topics:

    Inspections and Exemptions
    Required Documents and Publications Maintenance
    License and Personnel Requirements
    Reserve Source of Energy
    Equipment Testing
    Watchkeeping
    Logkeeping
Topic D: DSC & Alpha-Numeric ID Practice Test
- 48 questions covering these topics:

    Call Signs and SELCALs
    MMSI- MID and Ship Station I.D. Numbers
    MMSI; Group and Coast Station I.D. Numbers
    Inmarsat Mobile Numbers for B & F-77 Terminals
    Inmarsat Mobile Numbers for “C” Terminals
    DSC Format and Info Sent
    DSC Operations
    DSC Frequencies
Topic E: Distress, Urgency & Safety Communications Practice Test
-  60 questions covering these topics:

    Sending a Distress Alert
    Follow-On Voice Transmission
    Response to a Distress Alert
    Distress Relays
    Action-False Distress Alert
    Radio Silence – Resume Traffic
    Urgency Traffic
    Safety Traffic
    Frequencies
    Other Procedures
Topic F: Survival Craft Equip & S.A.R. Practice Test
-  60 questions covering these topics:

    SART- Activation and Survival Craft Operation
    SART – Radar Display – SAR – AIS SART
    SART: Testing and Battery Parameters
    EPIRB System Structure and Operation
    EPIRB Alerting and Features
    Homing and Locating Signals
    Survival Craft Transceivers
    On Scene Communications
    SAR-MCC-RCC: Systems & Procedures-1
    SAR-MCC-RCC: Systems & Procedures-2
Topic G: VHF-DSC Equipment & Communications Practice Test
-  12 questions covering these topics:

    VHF Controls, Power and Range
    VHF Channel System
Topic H: Maritime Safety Information (M.S.I.) Practice Test
-  48 questions covering these topics:

    Navtex-1: Operations
    Navtex-2: Programming
    Navtex-3: Message Format
    SafetyNETTM -1: Operations
    SafetyNETTM -2: Information
    Enhanced Group Calling (EGC)
    H.F. MSI
    NAVAREAs
Topic Ia: Inmarsat Equipment and Comms Practice Test 1
-30 questions covering these topics:

    Sat-C, Power up, Self-Test, Controls & Lamps
    Selecting an Inmarsat Ocean Region
    Inmarsat Log-in & Log-out
    Inmarsat General System Operations-1
    Inmarsat General System Operations-2

Topic Ib: Inmarsat Equipment and Comms Practice Test 2
- 48 questions covering these topics:

    Inmarsat-B or F77 Equipment and Operations
    Inmarsat-C: Equipment and Operations-1
    Inmarsat-C: Equipment and Operations-2
    Compare and Differentiate “B” and “C” Terminals
    Selecting L.E.S. and L.E.S. ID Numbers
    Inmarsat-B and F77- Address, Dialing and Voice
    Inmarsat-B - Address, Dialing and Telex
    Inmarsat-C Address to Ship Telex

Topic Ic: Inmarsat Equipment and Comms Practice Test 3
- 48 questions covering these topics:

    Address to Land Telex Terminal
    Address to a FAX Terminal
    Address to Internet, SMS or Special Addresses
    Inmarsat Distress Communications
    Satellite SAR-MCC-RCC
    EGC
    Equipment Faults and Maintenance-1
    Equipment Faults and Maintenance-2
Topic Ja: MF-HF Equipment and Comms Practice Test 1
-  36 questions covering these topics:

    MF-HF Panel Controls
    MF-HF Frequency–Simplex, Duplex, Half-Duplex
    MF-HF ITU Channels
    MF-HF Voice and Telex Channel Separation
    MF-HF Modulation, Bandwidth and Emissions
    MF-HF Voice Operations–Calling a Coast Station

Topic Jb: MF-HF Equipment and Comms Practice Test 2
-  48 questions covering these topics:

    MF-HF DSC Controller Call Programming
    MF-HF SITOR (NBDP) - Definitions
    MF-HF SITOR (NBDP) Technical Characteristics
    MF-HF ARQ Operation – Calling a Coast Station
    MF-HF ARQ Operation - Answerbacks
    MF-HF ARQ Operation – OP Codes & Procedures
    MF-HF ARQ Operation–Technical Characteristics
    MF-HF Addressing Modes

Topic Jc: MF-HF Equipment and Comms Practice Test 3
-  42 questions covering these topics:

    MF-HF FEC Operation-1
    MF-HF FEC Operation-2
    MF-HF Propagation-1; Day-Night-Winter-Summer
    MF-HF Propagation-2; Day-Night-Winter-Summer
    MF-HF DSC Controller Alert/Call Response
    Batteries
    MF-HF Equipment Faults and Testing

Untitled 1

Element 9

Element 9 Practice Test 1 Element 9 Practice Test 2
Element 9 Practice Test 3 Element 9 Practice Test 4
Element 9 Practice Test 5 Element 9 Practice Test 6

Element 1 Topic Tests - Random Ordered Questions

Topic A: VHF-DSC Equipment and Operation Practice Test
-  60 questions covering these topics:

    Frequency and Bandwidth
    Controls and Functions
    Receiver Technology
    Receiver Faults-1
    Receiver Faults-2
    Transmitter Technology
    Transmitter Faults-1
    Transmitter Faults-2
    Digital Selective Calling
    Antenna Systems
Topic B: MF-HF-DSC-SITOR (NBDP) Equipment and Operations Practice Test
-
  72 questions covering these topics:

    Frequencies and Bandwidth
    Controls, Functions and Displays
    Receiver Technology
    Receiver Faults-1
    Receiver Faults-2
    Transmitter Techmology
    Transmitter Faults-1
    Transmitter Faults-2
    DSC Operations
    SITOR (NBDP)-ARQ
    SITOR (NBDP)-FEC
    Antenna Systems
Topic C: Satellite Systems Practice Test
-
  60 questions covering these topics:

    Technology
    C-Terminals
    Long Range Identity Tracking
    MF-HF Frequency & Emission Selection
    Fleet-33-55-77 Terminals
    Fleet Broadband Terminals
    GPS
    Antenna Systems
    Equipment Faults and troubleshooting-1
    Equipment Faults and troubleshooting-2
    Equipment Faults and troubleshooting-3
Topic D: Other GMDSS Equipment Practice Test
-
  24 questions covering these topics:

    EPIRB
    SART
    Survival Craft Transceiver
    Navtex
Topic E: Power Sources Practice Test
-
 24 questions covering these topics:

    Batteries
    Battery Chargers and Power Sources
    Power Supplies-1
    Power Supplies-2
Topic F: Other Equipment and Networks Practice Test
36 questions covering these topics:

    Computers
    Computer Networks – Ethernet
    Local Area Networks- NMEA-0183
    Local Area Networks- NMEA-2000
    Depth Finders, Gyro Compass, SSAS, AIS
    ECDIS – Auto Pilots – Data Recorders
Topic G: Inspections, Installations and Instruments Practice Test
-  24 questions covering these topics:

    Equipment Installation
    Annual Inspections
    Test Equipment-1
    Test Equipment-2

Untitled 1

Element 8

Element 8 Practice Test 1 Element 8 Practice Test 2
Element 8 Practice Test 3 Element 8 Practice Test 4
Element 8 Practice Test 5 Element 8 Practice Test 6

Element 1 Topic Tests - Random Ordered Questions

Topic A: RADAR Principles Practice Test
-  60 questions covering these topics:

    Marine RADAR Systems
    Distance and Time
    Frequency and Wavelength
    Power, Pulse Width, PRR
    Range, Pulse Width, PRF
    Pulse Width - Pulse Repetition Rates
    Components-1
    Components-2
    Circuits-1
    Circuits-2
Topic B: Transmitting Systems Practice Test
-  48 questions covering these topics:

    Transmitting Systems
    Magnetrons
    Modulation
    Pulse Forming Networks Modulation
    TR - ATR - Circulators - Directional Couplers-1
    TR - ATR - Circulators - Directional Couplers-2
    Timer - Trigger - Synchronizer Circuits

Topic C: Receiving Systems Practice Test
-  60 questions covering these topics:

    Receiving Systems
    Mixers
    Local Oscillators
    Amplifiers
    Detectors - Video Amplifiers
    Automatic Frequency Control - AFC
    Sea Clutter - STC
    Power Supplies
    Interference Issues
    Miscellaneous
Topic D: Display & Control Systems Practice Test
-  60 questions covering these topics:

    Displays
    Video Amplifiers and Sweep Circuits
    Timing Circuits
    Fixed Range Markers
    Variable Range Markers
    EBL, Azimuth and True Bearing
    Memory Systems
    ARPA - CAS
    Display System Power Supplies
    Miscellaneous
Topic E: Antenna Systems Practice Test
-  30 questions covering these topics:

    Antenna Systems
    Transmission Lines
    Antenna to Display Interface
    Waveguides-1
    Waveguides-2

Topic F: Installation, Maintenance & Repair Practice Test
-  42 questions covering these topics:

    Equipment Faults-1
    Equipment Faults-2
    Equipment Faults-3
    Equipment Faults-4
    Maintenance
    Installation
    Safety

Page updated 11/10/2016