By using（）system a ship can send a distress message and know with certainty it will be received.

Can MF/HF radiotelephone receive the MSI sent from the coast stations alone?（）

All coast radio stations（）DSC installed for VHF and HF.

The frequency（）the safety message will be transmitted shall be included in DSC safety call.

Monitoring is especially important in a highly automated system which is dependent on careful（）procedure and format.

International Navtex service means the coordinated broadcast and automatic reception on（）khz of maritime safety information by narrow-band direct-printing telegraphy using English language.

The quality of EGC messages is（）affected by the position of the ship, the time of reception and climatic conditions.

On-scene communications will normally take place between（）.

Every lifeboat which is fitted with a fixed two-way（）radiotelephone apparatus with an antenna which is separately mounted shall be provided with arrangements for sitting and securing the antenna effectively in its operating position.

If the beacon is mounted at a wrong place, it may（）by sea water, chemicals, exhaust and vibrations.