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A hand-held VHF radio can serve as the primary communication device on smaller boats as well as a back-up for a fixed mount transceiver. The use of large scale integrated circuits and microprocessors makes it possible for even the smallest of these radios to provide virtually all of the capabilities and features of conventional radios. The major differences between the hand-helds and fixed mount radios are maximum transmitter power output and the non availability of digital selective calling in the hand held sets. Virtually all of these radios operate on all allowable transmit and receive channels, including all NOAA weather channels.
As with all marine VHF transceivers, hand-helds must provide a 1 watt transmit power selection in addition to whatever higher power may be available (usually 3-6 watts). The general considerations that govern the choice of a fixed mount VHF set apply to a hand-held radio. The receiver is the most costly part of the radio and its ability to separate the signal you need to hear from interfering signals may determine the radio's worth. Transmit power is a secondary consideration. Remember, communication on the marine VHF band is essentially line of sight. Unless the radio is connected to a fixed antenna, mounted at some height above the water, the one watt low power setting will usually be all you need for clear communication. Further, unless the radio is connected to an external power source it will be drawing energy from its internal battery. Battery life is greatly extended by using the low power setting.
Connecting
a hand-held radio to the boat's fix mount antenna can be very worthwhile. The
fixed mount antenna is a more efficient means for radiating transmitter power
than the necessarily small antenna on the radio. The added height of the fixed
mount antenna will increase the "radio horizon", the distance over
which you will be able to establish reliable communication. The antenna on many
hand-helds plug into an RF connector on the top of the set. With the antenna
removed a coaxial cable connected to a fixed mount antenna can be plugged into
the radio. If you elect to use this option be sure to secure the normal antenna
to the radio so that it will be immediately available when it is necessary to
use the set without the fixed antenna.
As
noted, all VHF radios are vital safety devices. Carrying a hand-held in addition
to a fixed mount set provides a valuable degree of additional security. The
hand-held may be a critical device in an emergency. Buying a high quality model
that is waterproof (submersible) can provide a possibly critical degree of
assurance that it will work when needed. Buying a radio capable of using
standard alkaline cells as an option to the normal rechargeable Ni-Cads or other
rechargeable battery can be a very desirable choice. It is difficult to
ascertain the state of charge of a Ni-Cad which may become depleted just when it
is needed most. Alkaline cells can be stored on board for at least a year with
little or no loss of stored energy. Choosing a fully waterproof set capable of
operating from alkaline cells is an obvious choice for a radio to be included in
an abandon ship bag or in a life raft. (Any battery or battery operated device
included in a life raft container must be carefully packaged to ensure that the
raft is protected from damage in the event a cell leaks its caustic active
material.)
> VHFHomepage >Hand-Held VHF Radios