What HF-band is generally suitable for long distance transmission if one of two stations is Located in twilight?
Distress MF communications should normally be operated:
In G3E mode – on simplex basis.
In J3E mode – on simplex basis.
In J3E mode – on duplex basis.
In G3E mode – on duplex basis.
MUF stands for:
Highest possible frequency that will be reflected by the ionosphere.
Most effective frequency, to make a connection with an HF-transmitter.
Highest possible frequency that can be made with an HF-transmitter on board.
Is it necessary to state the accounting code of the vessel in fully automated radio telex-traffic with a coast-station?
No, when AAIC is unknown, it will be asked for.
No, because the AAIC is included in the radio telex-identification.
It depend upon your location.
On area A1 the function “Reception of shore to ship distress alerts” is mainly based on:
The use of SART transponders.
The use of SARSAT COSPAS Epirbs.
A battery of 24 Volt supplies during 10 hours a current of 6 ampere. What is the capacity supplied?
Which of the following frequency bands would most likely provide reliable communication between two stations that are 15 miles apart?
The Very High Frequency (VHF) band.
The Medium Frequency (MF) band.
The High Frequency (HF) band.
The Low Frequency (LF) band.
The number of oscillations of a wave per seconds is called:
Via a coast-station radio medical advice is asked using NBDP. What command has to be given after ga +?
The number of oscillations of a wave per seconds is called:
To choose the HF-band, the time difference between 2 stations:
Is multiplied by the hour at the transmitting station.
In the Inmarsat Maritime Communications Handbook one can find information about:
2 digit code telex services.
Numbers of fax subscribers.
What do you do after receiving a VHF DSC DISTRESS call?
You set watch on VHF channel 16.
You set watch on channel 13.
You send immediately a DSC DISTRESS ACKNOWLEDGEMENT call.
You send immediately a DSC DISTRESS RELAY call.
The display of the DSC-controller on board is showing the following lines: RX: 002442000; CH87; D Sellcall Routine. We’re asked to listen on:
Channel Delta of the coast station.
Radio telephony-channel 7 in the 8 MHz band.
What are the NAVTEX messages categories which cannot be suppressed?
Of the AM-signal:
Amplitude is variable and frequency of the carrier wave is constant.
Both amplitude and frequency of the carrier wave are variable.
Is not dependant on the frequency and amplitude.
Amplitude and frequency of the carrier wave are constant.
A distress alert on board may only be transmitted on explicit order of:
The navigating officer on duty.
What does the abbreviation DSC means?
Distress and safety call.
Under GMDSS rules the trading area A1 can be considered to be:
Within range of VHF coast radio stations.
Within the coverage of Inmarsat.
Within range of MF coast radio stations.
Command of radio-traffic between vessels and coast stations lies:
Always with the coast station.
With the station that calls.
Give the command after ga + for the transmission of a “store and forward”-message with radio-telex:
On the MF/HF transmitter-receiver there is a sensitivity control. Another name for this is:
Moored in a harbour, transmitting with a mariphone is:
Allowed in emergency only.
Allowed in consultation with harbour master.
What is the two letter signal, to be used by flags, radiotelephony or radiotelegraphy, meaning “Calling All Ships”?
Which type of call will be sent by a ship adrift and needing the assistance of a tug? The weather is not bad and the ship will be aground 24 hours later.
With maintenance of batteries it is of primary importance that:
The space where the batteries are stored is properly ventilated.
There is proper relative humidity in the space where the batteries are stored.
There is an absolute free access to the battery space.
Which word will precede a safety message?
By the degree of selectivity of a receiver is meant:
Ability to receive all signals.
Ability to prevent variations in the strength of radio frequency signal received.
Ability to make weak stations audible.
Ability to distinguish weak stations from adjacent stronger stations.
What does the abbreviation VHF means?
Variable Hertz Frequency.
The batteries must be placed in a well ventilated place, so that:
The person can work in the compartment.
The detonating gas can be discharged.
The production of detonating gas can be prevented.
There is sufficient oxygen available for optimum working of the batteries.
A VHF transmission range is mainly determined by:
The height of the aerial.
The transmission power, propagation and the quality of the receiver.
Whether it is radio-telephony, radio-telex or DSC.
All designated SAR aircraft and civil aircraft carry equipment operating on the international aeronautical distress frequencies (amplitude modulation). The aeronautical distress frequencies are:
123,8 MHz and/or 247,6 MHz.
243,1 MHz and/or 486,2 MHz.
127,8 MHz and/or 71,6 MHz.
121,5 MHz and/or 243,0 MHz.
On board one can use the reflections in the ionosphere by the right choice of:
The length of the aerial.
The time of transmission.
The mode of transmission.
A wire aerial for an MF/HF-transmitter must be suspended between isolators:
To prevent contact with earth.
To prevent burns when touching the aerial.
To make the way for aerial currents as long as possible.
When sending an OBS (weather report) with Inmarsat one should use Service Code “41”. With this address the weather report will always be transmitted to:
The meteorological office of the ship’s flag state.
MET office Washington, this office will take care of further dispatch of the weather reports.
The meteorological station connected with the CES used.
The emergency battery of a GMDSS portophone:
Must be tested once a week.
Must be replaced before the expiry date is exceeded.
Must be charged after expiry date.
At what minimum height above sea level a SART transponder must be mounted?
The good working of a SART transponder doesn’t depend on the height above sea level.
You want to send a DSC-call in connection with a shore telephone-call. You must choose:
What is the purpose of the radiotelephony two tone alarm?
Alert COSPAS/SARSAT satellites.
Activate bridge watchkeeping receivers and attract the attention of the person on watch.
Attract the attention of the person on watch.
Activate bridge watchkeeping receivers.
Inmarsat is short for:
International Maritime Satellite System.
International Maritime Satellite Organisation.
International Maritime Safety Organisation.
Internal Marine Safety Organisation.
In the traffic list a coast-station indicates that there is a radio telex-message for a vessel. To call for the message one should put in:
After ga + the radio telex-command msg + ?
After ga + ? the radio telex-command msg +.
After ga + the radio telex-command msg +.
After ga + the telex number of the ship.
The traffic list of a coast-station is a list of:
Call-signs of ships for which a radio-telephone call, a telegram or another call is intended.
Name of ship’s scheduled for berthing.
Pertinent navigational and weather information.
Names of ships which, on behalf of safety at sea, are being routed by a traffic control system.
In radio telephony what is the “URGENCY CALL” which should be used to indicate that you have a very urgent message to transmit concerning the safety of another vessel or person?
SECURITE-SECURITE (3 times).
The ID of an Inmarsat-M station on board starts with:
The authority to order the use of distress signal or distress alerts is:
The first person to discover the distress situation.
The person designated to maintain communication during distress situations.
The impedance of a coax cable for the VHF-set depends on:
The structure dimensions and the material of the coax cable.
The length of the coax cable.
The temperature of the cable.
The way in which the feed line is controlled.
The propagation of radio-signals in the VHF-band is:
Dependent on the hour of transmission (day or night).
Dependent on the power emmited and the temperature of the atmosphere.
Which word will precede a routine message?
No specific word will precede a routine message.
The altitude effect of the reflection of radio waves in the ionosphere on the transmission range also depends on:
The sensitivity of the receiver.
The position of the pre-selector tuning-button.
A DSC-notice should be sent on VHF-channel:
Which of the following frequencies is used by the NAVTEX system?
Define the class of emission G3E:
Radiotelex and DSC – Frequency shift keying of carrier with error correction.
Radiotelephony – Phase Modulation.
Radiotelephony – Frequency Modulation.
Radiotelex and DSC – Frequency shift keying of sub-carrier with error correction.
The word NAVTEX is spelled conform the international phonetic alphabet:
November, Apple, Victoria, Tango, Echo, X-mas.
November, Able, Valencia, Tripoli, Echo, Xantippe.
November, Alfa, Victor, Tango, Echo, X-ray.
November, Anna, Victor, Tango, Eduard, X-ray.
The type of Inmarsat station A, B, C, M is recognized by:
The first four digits of the identification.
Last digit of the identification.
The first two digits of the identification.
The first digit of the identification.
What is the meaning of the abbreviation “RQ” at the end of a DSC sequence?
Acknowledgement broadcast.
What is understood by carrier frequency?
Frequency of the carrier wave.
The frequency of upper side band (UBS).
The frequency actually used by transmitter and receiver.
Frequency of single side band.
A vessel is equipped for all sea areas. In the middle of the Indian Ocean the EGC-receiver appears out of order. Is it still possible to receive MSI-messages?
Yes, with the MF/HF-radio telex.
According to the rules of GMDSS all vessels have to be equipped with:
A possibility to receive MSI.
At least three mariphones.
By FleetNET communication is understood:
An urgent message for all ships in a particular area.
A MSI-message destined for ships in specific geographical area.
A HF-NBDP-message destined for ships in a certain geographical area.
An EGC-message destined for ships with the same group call number.
According to the rules of GMDSS all vessels have to be equipped with:
At least three mariphones.
A possibility to receive MSI.
An area within the radiotelephone coverage of at least one VHF coast station in which continuous DSC alerting is available is called:
According to the rules of GMDSS vessels equipped for all sea areas have to be provided with:
406,0 MHz Cospas-Sarsat EPIRB.
1,6 GHz Inmarsat/DSC EPIRB.
121,5/243,0 MHz VHF EPIRB.
On area A1 the function “Transmission of ship to shore distress alerts” is mainly based on:
The use of SART transponders.
A SART must be visible on the ship’s radar from a distance of at least:
Which class of emission is used for VHF radio telephony transmissions?
According to the rule of GMDSS, channel 70 is used for:
Distress and urgency traffic.
Which International Convention introduced the GMDSS?
Define the class of emission H3E:
Radiotelex and DSC – Frequency shift keying of carrier with error correction.
Radiotelex and DSC – Frequency shift keying of sub-carrier with error correction.
Radiotelephony – Single sideband full carrier.
Radiotelephony – Frequency modulation.
On the MF/HF transmitter-receiver there is a sensitivity control. Another name for this is:
For how long time should a “SARSAT COSPAS” epirb be able to operate on its batteries?
In radio-telex distress traffic preference is given to FEC because:
The system automatically requests repetition when reception garbled.
Everybody can read along.
By frequency is meant:
Time lapse of vibrations.
Number of vibrations per unit of time.
Your vessel is not in distress and not taking part in a distress operation. How would you impose radio silence on vessels which are interfering the distress traffic?
The ship-shore HF-telephone-channel 2 228 consists of the frequencies 22 081,0 kHz and 22 777,0 kHz. In case of manual operation, one should tune the receiver on:
The common receiving frequency for the 22 MHz band.
Via Inmarsat-C a message is sent to an Inmarsat-C mailbox with a positive delivery notification (PDN). The ground station will:
Send a PDN, if the message has arrived in the mailbox.
Not send any PDN for this message.
send no PDN’s with messages intended for the mailbox.
Send a PDN, as soon as the message is collected from the mailbox.
The hydrostatic release of an EPIRB should be changed:
MF communication is usually provided by:
When a DSC-message of the “distress” category is received, in order to start distress alert communication in so far as not indicated in the alert, you will switch to VHF channel:
Modulation is:
To enhance the side bands in relation to the carrier wave.
Blending LF & HF signals.
A distress-call, onboard via RCC, may only be given Receipt if:
OSC from the RCC concerned invites the vessels.
The OOW deems it necessary.