Essentially, the Range is determined by the position & length of the Antenna and how many Watts of power the device is able to put out . A hand held VHF only puts out 5watts of power, while a fixed mount device puts out 25watts.
Read moreWhat is the possible range of a handheld marine VHF?
Transmission Range The general rule of thumb, for hand-held VHF radios, is that 1 Watt is approximately 1 nautical mile of range (example: a 5 Watt VHF radio will have an approximate 5 nautical mile range when set to the 5 Watt setting). Most hand-held VHF radios are between 1 Watts and 6 Watts.
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