[单选题]----------all ships in a large area being alerted, an:” area call “will normally be transmitted so That only those ships in the vicinity of the distress incident are alerted
[单选题]If a fitted two-way VHF radiotelephone apparatus is fitted in the lifeboat,it shall be install in a cabin ____to accommodate both the equipment and person using it .
[问答题]DSC uses a DIGITAL signal to send a specific set of information.The information that can be passed by a DSC call includes: ①The caller’s MMSI(a number that uniquely identifies that caller,similar to a phone number). ②The MMSI of the unit being called.This can be a specific unit or a group of units(for example,all Coast Guard units). ③The caller’s location,and time of location.This can be derived directly from an interface to a GPS/SatNav receiver,or it can be entered manually.Location and time of location are normally only transmitted with a distress alert. ④The requested working frequency and mode.This is the frequency and mode of emissions that will be used to transact business.DSC is only used for call set-up. Once the call is established the two parties change to a working frequency and mode to continue the call. ⑤The priority of call (Distress,Urgent,Safety,Rountine).DSC can be used for anything from distress calls,to setting up a routine phone patch through a commercial coast station. ⑥For distress calls,the DSC call can even indicate the type of emergency(fire,flooding,ect).
[单选题]Every radio installation shall be protected against ____,extremes of temperature and other adverse environmental conditions.