GMDSS普通操作员 第04讲：Passage 30 第04讲：Passage 30.ppt

航运系航海教研室 航运系航海教研室 航运系航海教研室 航运系航海教研室 航运系航海教研室 航运系航海教研室 航运系航海教研室 航运系航海教研室 航运系航海教研室 航运系航海教研室 Passage 30 The frequencies 2,187.5 kHz, 4,207.5 kHz, 6,312.0 kHz, 8,414.5 kHz, 12,577.0 kHz, 16,804.5 kHz, and 156.525 MHz may be used for DSC by coast and ship stations on a simplex basis for distress and safety purposes. The provisions and procedures for distress and safety calling are contained in CCIR Recommendation 541 as modified by Sec. 80,103 (C) of this part. Coast and ship stations may also use DSC techniques for general calling purposes on their assigned working frequencies in 2,000-27,500 kHz bands and on those frequencies in the 156-162 MHz band which are allocated for maritime control, commercial, non-commercial and public correspondence communications. Passage 30 1. How many frequencies are allocated for distress, urgency and safety purposes in DSC service? A. Only one. B. Seven. C. Five. D. Three, 2,187.5 kHz, 8,414.5 kHz and Channel 70. 正确答案：B Passage 30 2. What does the abbreviation Sec. mean in the first paragraph? A. Second. B. Secretary. C. Securities and Exchange Commission. D. Section. 正确答案：D Passage 30 3. What is the best title of the passage? A. Allocation of Frequencies for DSC. B. 2 ,189.5 kHz in DSC Service. C. Channel 70 in DSC Service. D. Usage of Frequencies for DSC. 正确答案：D Passage 30 4. What is International Calling Frequencies? A. International Calling Frequencies are often dedicated for communications between ship and coast stations bearing same nationality. B. International Calling Frequencies are often used by ship and coast stations belong to different nations. C. They are often used by Chinese vessels intending call Chinese coast radio stations. D. International Calling Frequencies are often dedicated for communications between ship and coast stations bearing same nationality. 正确答案：B Passage 30 5. What is(are) the purpose(s)