Each week Bateaux.com will propose you a question about the boat license. To validate your skills or even to discover unexplored areas. This week, we tackle the question about the range of VHF.
At sea, what is the range of a portable VHF?
The VHF uses a frequency band between 156 and 162 MHz. In these frequencies, we consider that the waves propagate in a straight line. This is why we speak of "optical range". It is therefore understood that a VHF transmission will be blocked by a cliff or even by the rotundity of the earth. This is also why you should try to install the antenna of a fixed VHF as high as possible (on the cabin for a motorboat or at the top of the mast of a sailboat).
The range of a portable VHF, assuming that we are 1 m above the water will not exceed 10 miles. It was therefore necessary to answer A to the question. Certainly if the receiver is higher, the range will increase as can be seen on the diagram below.
