These were the "output" side of the old "public correspondence" (Marine Operator) channels. They are now used for AIS (Automatic Identification System) by ships at sea, and are required for entry to certain VTMS harbors.
There are 33 Inland Economic Areas where there are no navigable waterways and therefore any frequencies allocated for marine use are not needed there for boats. In those areas, these particular frequencies may be licensed for land mobile (Part 90) interoperability use.
There are 33 Inland Economic Areas where there are no navigable waterways and therefore any frequencies allocated for marine use are not needed there for boats. In those areas, these particular frequencies may be licensed for land mobile (Part 90) interoperability use.