comdtinst m2400.1f - US Coast Guard Response Boat-Medium

ANNEX B - MARINE INFORMATION BROADCAST SCHEDULES (REFER NOTE AT END OF
ANNEX B)
Emissions: MF/HF (CW/100HA1A); 518 kHz (NAVTEX/304HF1B); 2-30 MHz
(SITOR/300HF1B); 2-30 MHz (Voice/2K8J3E); 157.1 MHz
(VOICE/16KF3E); (FAX/4KF3C) (NARROW BAND FAX/2K8F3C).
500 kHz (100HA1A/1K03H2Z), 2183.4 (2182) kHz (2K8H3E/J3E),
and 156.8 MHz (16KF3E) may be used to announce scheduled
marine information broadcasts. These frequencies may also
be used to transmit urgency and safety signals and
urgency messages. Safety messages, whenever possible,
should be transmitted on a working frequency assigned for
broadcast purposes; however, transmissions of short
safety messages on 2183.4 (2182) kHz and 156.8 MHz are
permitted provided a certain situation warrants such
action.
Broadcasts of maritime safety information on Channel 22A
(157.1 MHz), the ship station transmit frequency portion
of International Channel 22, are not compatible with the
international duplex arrangement of the channel (coast
transmit 161.7 MHz, ship transmit 157.1 MHz). As a
result, approximately 50% of foreign flag vessels
in U.S. waters cannot receive Coast Guard maritime safety
broadcasts on 157.1 MHz, even though these ships do carry
VHF radios and do monitor Channel 16 (156.8 MHz).
For additional information concerning marine broadcasts,
refer to Chapter 13 of COMDTINST M16500.7 (Aids to
Navigation manual), Chapter 14 of COMDTINST M2000.3 and/or
instructions promulgated by the appropriate district
commander. The shore stations that are designated to make
scheduled broadcasts and their assigned working
frequencies are as follows.
The abbreviations listed under the subject column are as
follows:
WX - Scheduled weather broadcasts
HD - Scheduled hydrographic information broadcasts
NTM- Scheduled Notice to Mariners broadcasts
! - Unscheduled warning broadcasts only
# - The SSB carrier or dial frequency for the 2-3 MHz
voice broadcast frequencies are located 1.4 kHz below
the above assigned frequencies.
B-2