Do not Use a Port Operations Channel unless it is related to Operational Handling, Movement and Safety of Ships.

DO NOT Make non-essential superfluous signals and correspondence.

DO NOT Transmit without using the correct procedures.

DO NOT Occupy a particular channel under poor communication conditions.

Do not Use offensive language.

1. Before transmitting a signal, think about the subjects, which have to be communicated and, if necessary, prepare notes to ensure that valuable time is not wasted on the busy International Channel.

2. Use the lowest transmitter power necessary for satisfactory communications.

3. Listen, before transmitting a signal from your equipment to make sure that that the channel is not already occupied. This avoids unnecessary interference.

4. Whenever possible, call on a Working Channel. If a working channel is not available, Channel 16 can be used, provided it is occupied for Distress purposes. On channel 16 after your initial call to a ship or shore station subsequent calls may only be made at 3 minutes intervals. Do not occupy a channel unnecessarily – if need be, try another assigned and appropriate channel.

5. If a change of channel is found necessary, advise the other station and seek confirmation before changing.

6. If spelling of difficult words is necessary use the Phonetic Alphabet. This is contained in the International Radio Regulations and International Code of Signals, amongst many other books.

7. Instructions given on communication matters by shore stations must be complied with. Communications must be carried out on the channel indicated by shore station. When a change of channel is requested, this must be acknowledged by the ship, before the change is made. If instructed by a shore station to stop transmitting, no further communications are to be made, until further advice is received – the shore station may be handling Distress of Safety communications.

8. When calling another ship, the ship called, indicates which working channel is to be used. The calling ship acknowledges acceptance before changing channel. To avoid unnecessary interference the Listening Procedure in item 3 above must be followed, before communications start on any channel.

9. When at sea, ships fitted with VHF equipment, should maintain listening watch on channel 16. In certain cases, Governments may require ships to keep watch on other channels.

2. Answer the following questions

1. What are the limiting factors for transmission and receiving range of VHF signals?

2. What convention stipulates the carriage of the marine communications equipment?

3. What messages have absolute priority over all other communications?

4. What should be done on receipt of a Distress Call?

5. Why is use of Cellular radiotelephones for Distress and Safety purposes strongly discouraged?

6. What are prohibitions regarding VHF telephony?

3. Summarize the steps of proper usage the VHF telephony

4. Speak on routine communications using VHF telephony, radio telex, DSC.

Unit 8

1. Read and translate the text

Parallel index techniques

Investigation of casualties where radar was being used as an aid to navigation prior to the vessel grounding have indicated that inadequate monitoring of the ship’s position contributed to many of the accidents. Parallel index techniques provide valuable assistance to position monitoring in relation to a pre-determined passage plan, and would have helped to avoid these groundings. Parallel indexing should be practiced in clear weather during straightforward passages, so that watchkeepers become thoroughly familiar with the technique before attempting it in confined difficult passages, or at night, or in restricted visibility.

The principles of parallel index plotting can be applied, using electronic index lines, to both relative and true motion displays. These index lines can be stored and called up when required on all modes of display. Electronic index lines also enable the operator to switch ranges. With such a facility care must be taken during passage planning to ensure that the correct parallel index lines for the intended voyage are available for retrieval.

On a relative motion display, the echo of a fixed object will move across the display in a direction and at a speed, which is the exact reciprocal of own ship’s ground track. Parallel indexing uses the principle of relative motion, and reference is first made to the chart and the planned ground track. The index line is drawn parallel to the planned ground track with a perpendicular distance (cross index range of offset) equal to the planned passing distance off the object. Observation of the fixed object’s echo moving along the index line will provide a continuous indication of whether the ship is maintaining the planned track. Any displacement of the echo from the index line will immediately indicate that own ship is not maintaining the desired track ground, enabling corrective action to be taken.

Electronic parallel index lines are drawn and used in the same way on true motion displays in both sea-stabilised and ground-stabilised mode. Parallel index lines are fixed relative to the trace origin (i.e. to own ship) and will consequently move across the display at the same rate and in the same direction as own ship. Being drawn parallel to the planned chartered track, and offset at the required passing distance off the selected fixed mark, the echo of the mark will move along the index line as long as the ship remains on track. Any displacement of the fixed mark’s echo from the index line will indicate that the ship is off track enabling corrective action to be taken.

Parallel indexing is an aid to safe navigation and does not replace the requirement for position fixing at regular intervals using all appropriate methods available including visual checks.

When using radar for position fixing and monitoring, check:

• the radar’s overall performance;

• the identity of fixed objects;

• the gyro error and accuracy of the heading marker alignment;

• the accuracy of the variable range marker and bearing cursor;

• that parallel index lines are correctly positioned on a suitable display.

Some older radars may still have reflection plotters. It is important to remember that parallel index lines drawn on reflection plotters apply to only one range scale. In addition to all other precautions necessary for the safe use of radar information, particular care must therefore be taken when changing range scales.

Unit 9

1. Read and translate the text