Just When You Committed the VHF Channels to Memory

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Just When You Committed the VHF Channels to Memory

Safety Moment, Cruising Club of America, SF Station, March 2017

Chuck Hawley

I spent much of the fall and winter months working on a handbook to accompany US Sailing’s Safety at Sea seminars. Many CCA members have been supporters of Safety at Sea courses over the years that the list truly reads like a Who’s Who of respected US offshore sailors: Capt. John Bonds, John Rousmaniere, Sheila McCurdy, Ralph Naranjo, Rich duMoulin, Ron Trossbach and many, many others. The resulting book, which leverages substantial work from CCA member Sally Honey, comprises 15 chapters on key topics of offshore marine safety, including a lengthy chapter on Emergency Communications.

As luck would have it, on the day that I received my first printed copy of the Safety at Sea book, I also discovered that it was already out of date. While verifying some information on the Coast Guard’s Navigation Center web site, I was surprised to find out that the VHF channels that have been in common use since around 1970 are changing. Or at least some of them are changing. While this won’t make your current radio obsolete in the future, it will cause confusion as we transition from the old to the new.

This relates to two somewhat obscure aspects of VHF-FM marine radios: the USA-CAN-INT switch, and the “A” character on the channel display. The mode switch for selection US or Canadian or International channels is probably known more for becoming a barrier to communications when set to the wrong position; many channels are different and cause confusion when you’re on INT and you should be on USA.

This relates directly to the little “A” or “alpha” that is appended to the end of many US channels. This designates channels which are duplex in some parts of the world (transmitting and receiving on different frequencies) but which are simplex in the US. Popular examples include 21A, 22A and 23A, channels that are used by the Coast Guard. Those channels are different when operating in International mode, thus the Alpha designation.

Apparently in an attempt to simplify this potentially confusing issue, the International Telecommunications Union has renumbered these alpha channels in the U.S. They will now be known as 1021, 2022, and 1023 with no “a” or “alpha” suffix. Rather than provide you with a complete list, you can simply add 1,000 to any channel that currently has the “a” suffix, or check this link on the Coast Guard’s Navigation Center page.

Some VHF transceivers already have the ability to show the four-digit channel numbers, and all new models will have this ability. How soon stations will be requesting that you “switch and answer on channel 1022” is anyone’s guess. While an imperfect solution, it may prove easier to have numeric-only channel designations in the U.S. from now on.