Which of the following frequencies is not used for DSC service
A: 829lkHz
B: 8414.5 kHz
C: 16804.5 kHz
D: 4207.5 kHz
A: 829lkHz
B: 8414.5 kHz
C: 16804.5 kHz
D: 4207.5 kHz
A
举一反三
- All of the following are DSC watch-keeping frequencies, except( ) A: . 2187.5 kHz. B: 2182 kHz C: 12577 kHz D: 6312 kHz
- 根据要求,配备MF/HF设备的船舶应在( )DSC频率上保持连续值守。 A: 2187.5/4207.5kHz B: 2187.5/8414.5 kHz C: 4207.5/8414.5 kHz D: 6312/12577 kHzD
- . Which of the following frequencies is as international distress and safety frequencies on MF for radio telephone? A: 2187.5 kHz B: 2174.5 kHz C: 2182kHz D: 2177. OkHz
- Which of the following MF frequencies is internationally allocated for use for transmitting NEVTEX-type broadcasts? A: 518 kHz using FEC mode. B: 4. 209. 5 kHz using FE mode. C: 486 kHz using FBC mode in China. D: All of the above.
- Which of the following frequencies are not DSC distress and safety frequency? A: 2187.5kHz. 4207.5kHz B: . 6312kHz. 8414.5kHz C: 2182kHz. 829lkHz D: 12577kHz.16804.5kHz
内容
- 0
标准 CD 音频采样率是 A: 5 KHZ B: 11 KHZ C: 22 KHZ D: 44 KHZ
- 1
以下( )不是国际NAVTEX广播频率。 A: 490 kHz B: 518 kHz C: 4209.5 kHz D: 486 kHz
- 2
广播超外差接收机的中频为465 KHz，当接收700 KHz电台信号时，其本振信号频率为（ ）。 A: 1165 KHz B: 235 KHz C: 1630 KHz D: 935 KHz
- 3
____________的采样频率是目前音频卡所支持的。 A: 20 kHz B: 22.05 kHz C: 100 kHz D: 50 kHz
- 4
如图所示振荡电路，其振荡频率约为（ ）。[img=428x484]1802f435f02a3bd.png[/img] A: 1.94 kHz B: 19.4 kHz C: 3.88 kHz D: 38.8 kHz