Is SSB line of sight?

For example, if you and a friend are using handheld transceivers (HTs) with a typical output power of 5 watts, you can expect your range to be about 5 miles maximum . If you’re using a repeater, however, you should be able to talk much farther.

While nearly all boats carry a VHF, its maximum range isn’t more than about 25 miles. This is because VHF radio waves travel in a straight line or line of sight. In contrast, waves from marine single-sideband (SSB) radios travel up to the F layer of the ionosphere, 75 to about 250 miles above the Earth .31 May 2008

Transmitter power is limited to 4 watts in the US and the EU. CB radios have a range of about 3 miles (4.8 km) to 20 miles (32 km) depending on terrain, for line of sight communication; however, various radio propagation conditions may intermittently allow communication over much greater distances.