can you pls give some examples of sea and air transceivers?

Answer 1

This depends on the country you are in
Due to Frequency allocations
May I suggest you type into your search bar sea and air or (Aircraft and Marine Trasceivers) and (Radio Frequency Allocations)
For HF High Frequency
VHF Very High Frequency
Shortwave
Here are a couple of links
http://wireless.fcc.gov/marine/vhfchanl.html
http://www.dxzone.com/catalog/Operating_Aids?Radio_Spectrum
You could type in Communication Transceivers into the search bar Good Hunting