简答题 Coastal radio stations keep a constant watch on distress frequencies. What frequencies are they? 

简答题 According to the SOLAS, which radio equipment is not necessary for the ships sailing in the sea area A2?

简答题 What should a signal be prefixed by for distress traffic by radiotelephony?

简答题 What does MAYDAY mean in marine communications?

简答题  What should be included in MAYDAY messages?

简答题 Which channel is designated for VHF DSC alerting?

简答题  What should a station do when transmitting an inadvertent distress alert or call?

简答题 Which parties are those on-scene communications carried out between?