Filter
Top Products
FM-4000Page 76
15 CHANNEL ASSIGNMENTS
This chapter provides the VHF Marine Channel assignments for U.S.A. and
International use. Below are listed some data about the charts.
1. VTS. Where indicated, these channels are part of the U.S. Coast Guard’s
Vessel Traffic System.
2. Alpha channel numbers, that is, channel numbers followed by the letter A
(such as Channel 07A) are simplex channels on the U.S.A. or Canadian
channel assignments whose counterparts in the International assignments
are duplex channels. International channels do not use “alpha” numbers.
If you call the Coast Guard on Channel 16, they will sometimes ask you to
“go to channel 22 Alpha.” This is a channel assigned to U.S.A, and Cana-
dian Coast Guards for handling distress and other calls. If your radio is set
for International operation you will go to Channel 22 instead of 22A, and
will not be able to communicate with the Coast Guard. To use Channel
22A, your radio must be set for USA or Canada operation, usually by a U/
I/C (USA/International/Canada) control or combination of controls. Chan-
nel 22 (without an “A”) is an International duplex channel for port opera-
tions. Some radios indicate an “A” adjacent to the alpha channels on the
display; on others “alpha” is not indicated but the proper channel is se-
lected based on the U/I/C setting.
3. Bridge-to-Bridge channels (for example, Channel 13) are for use by bridge
operators on intercoastal waterways and rivers. It is also used by marine
vessels in the vicinity of these bridges for navigation and for communicat-
ing with the bridge operators. Note that a limit of 1 Watt is specified for
these channels. See page 27 for additional information.
4. The S/D column on the chart indicates either S (simplex) or D (duplex). Sim-
plex means transmitting and receiving on the same frequency. Only one party
at a time can talk, unlike a telephone. Be sure to say “over” and release your
microphone push-to-talk switch at the end of each transmission. Duplex op-
eration involves the use of one frequency for transmitting and a separate fre-
quency for receiving. On channels specified as duplex on the charts, correct
mode of operation is established automatically by your radio when you select a
channel; you cannot change the mode. And you still must release the push-to-
talk switch after each transmission in order to listen to the radio.
5. Channels normally used by recreational boaters are those that include the
term “non-commercial” in the Channel Use column of the chart. Some of
these are shared with other users and some are used only in certain geo-
graphic regions.
6. Marine vessels equipped with VHF radios are required to monitor Channel 16.