SSB / Ham
You probably know this, but in case you may not, many boats use what is called a Marine Single-Sideband (SSB) radio. Like a Ham radio, it is High-Frequency. In fact, an HF Ham rig is a sub-species of SSB. Like Ham, Marine SSB has its regulations and its frequencies. Many of them are referred to as channels, but the designations are related to the frequency rather than the wave length. Thus, there is never reference to 10 or 20 meters, for example, but to 4 megs, 6 megs, etc. The type of traffic ( I am referring to distance and propagation ) that is done on 20 meters in Ham radio, will typically be done on 12 megs with Marine SSB. Some rigs are legal for both Ham and Marine SSB, but many are not. A typical Ham rig is not, although its capability (but not legality) can be expanded by clipping a single wire! Many SSB rigs lack the ability to tune to a frequency, rather than a channel, so you can get stuck there, too. But, there are plenty of rigs that will do both, in which case you want to make sure you have one that can be tuned with a dial, rather than numeric entry, since you may be changing frequencies to find an open one. By the way, the FCC does, in fact, monitor SSB transmissions, and can tell if a Ham rig is slightly off frequency, which it often is. It is legal to listen to Ham with a Marine SSB, and to transmit in the case of emergency. I am sure those reccommended books will give you much more to chew on. Good Luck.Tim (XE2-KC6-GIT)