VHF radio is one of the very important navigational instruments on board,（）messages can be sent.

In the GMDSS, MSI broadcasts will be made on two dedicated systems:（）and（）.

The broadcast will normally be made on the two listed frequencies simultaneously except during transmitter maintenance periods when the broadcast will be made on the two frequencies（）.

VHF发射机输出功率测试是指（）。

On offshore drilling units，each EPIRB or SART must be tested once every（）.

（）will be broadcast every one hour on VHF Channel 6.

（）will be broadcast every one hour on VHF Channel 6.

为什么VHF通信属于近距离通信？

船用VHF通信设备属于（）距离的通信设备。

VHF telephone（）

Vessels wishing to communicate with the Port Health Officer should do（）on VHF Channel 14.

Which action should you take after sending a false distress alert on VHF?（）