A common question posed to us at CH Smith is what the difference is in transmission Range between a hand held VHF (very high frequency) Radio and a fixed mount?

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.

How does this affect the range?

Well the greater the Wattage of your device, the further its signal will be received. So obviously the fixed mount VHF radio is going to be able to reach a lot further than a hand held one. Also the higher the Antenna, the better the Range.

Positioning

As far as the positioning is concerned, a VHF signal travels in a straight Line and therefore is unable to be reflected off the ionosphere, as lower Frequency signals are. Due to the Range being restricted to ''line of sight'', when other vessels pass behind the curve of the earth, the connection is lost. So, the higher above sea level the Antenna is, the greater Range the VHF device will have.

Your typical Ship to Ship Range of a fixed VHF radio with a masthead Antenna will be approximately 20km. This will of Course increase as the height above sea level increases, or the Antenna you''re connecting to is at a greater height. A hand held radio, on the other hand, in ideal conditions can be expected to reach about 15km maximum.

Therefore, depending on how far away from shore you wish to travel, determines which VHF radio would be best suited to you.

For more information on VHF Radios, please do not hesitate to contact us in store or online.