Radio reference for ham operators and mariners at sea: the HF nets people actually check into, the GMDSS distress channels every operator should know, the US VHF marine channels, and where to pull HF weather when underway.
HF maritime mobile nets
14.300 MHz on 20 meters is the global maritime mobile calling frequency. If you have HF aboard, that is the channel to monitor when underway.
14.300 MHz, Maritime Mobile Service Net. 1600 to 0200 UTC daily, Atlantic and Caribbean. The longest-running maritime mobile net. Emergency traffic, position reports, weather relays. Monitored continuously by the USCG.
14.300 MHz, Pacific Maritime Mobile. 0300 UTC daily, Pacific. Yacht-focused. Cruisers in the Pacific Northwest, Mexico, French Polynesia.
14.300 MHz, Pacific Seafarers Net. 0330 UTC daily, Pacific basin. Trans-Pacific yacht position reporting and weather. Picks up where Pacific Maritime hands off.
7.086 MHz LSB, Caribbean Cocktail Net. 2300 UTC daily, Caribbean. Social, weather, and position reports for the Eastern Caribbean.
7.241 MHz, Caribbean Maritime Mobile. 1130 UTC daily, Caribbean. Morning net with weather from David Jones at the Caribbean Weather Center.
7.158 MHz, Atlantic Crossroads. 1100 UTC daily, North Atlantic. Trans-Atlantic crossers: Bermuda, the Azores, the Caribbean.
7.286 MHz, Salty Dawg Net. 0030 UTC daily, November to May, US East coast to the Caribbean. Run by the Salty Dawg Sailing Association during the southbound and Caribbean season.
14.315 MHz, Trans-Tasman Net. 0700 and 1900 UTC daily, Australia, New Zealand, Pacific. Australia to New Zealand passages, Coral Sea, Tasman crossings.
14.290 MHz, Comodoros Net. 1300 UTC daily, Caribbean. Spanish and English. Cruisers around Cuba, the Dominican Republic, Puerto Rico.
14.300 MHz, Boatwatch. Monitored around the clock, worldwide. Not a scheduled net. Vessels and shore stations watch it for overdue boats and emergency traffic.
GMDSS distress and calling frequencies
A DSC distress alert triggers an automated, position-stamped distress call to every DSC-equipped receiver in range, relayed by coast stations through the GMDSS network. Anyone with a DSC radio and an MMSI should know how to fire one.
HF voice (SSB), distress and safety:
2182 kHz (2 MHz band). Legacy MF distress. Still monitored by the USCG.
4125 kHz (4 MHz band). Short-range coastal.
6215 kHz (6 MHz band). Coastal and nearshore.
8291 kHz (8 MHz band). Open-ocean primary.
12290 kHz (12 MHz band). Long-range daylight.
16420 kHz (16 MHz band). Long-range daylight.
DSC, digital selective calling:
2187.5 kHz (2 MHz band)
4207.5 kHz (4 MHz band)
6312 kHz (6 MHz band)
8414.5 kHz (8 MHz band)
12577 kHz (12 MHz band)
16804.5 kHz (16 MHz band)
156.525 MHz (VHF Channel 70). DSC only. No voice on Channel 70.
US VHF marine channels
Channel 16, 156.800 MHz. Distress, safety, and calling. A required watch for most commercial vessels.
Channel 70, 156.525 MHz. DSC only, no voice. Radios use this automatically for distress alerts.
Channel 22A, 157.100 MHz. USCG working frequency. After a Channel 16 hail the Coast Guard usually moves you here.
Channel 13, 156.650 MHz. Bridge-to-bridge navigation safety and harbor traffic, low power at 1 W.
Channel 9, 156.450 MHz. Recreational calling channel. An alternative to Channel 16 for non-distress hails.
Channel 6, 156.300 MHz. Intership safety. Required for any vessel with a VHF.
Channels 68, 69, 71, 72, 78A, from 156.425 MHz up. Recreational working channels. Move here after calling on 16 or 9.
Channels WX1 to WX7, 162.400 to 162.550 MHz. NOAA Weather Radio. Continuous regional broadcast, receive only.
HF weather and safety broadcasts
NAVTEX (automated text):
518 kHz, international English. Coastal warnings and weather forecasts. Print-quality FEC text on a dedicated NAVTEX receiver.
490 kHz, national. The same content as 518 in the local language for the broadcast area.
4209.5 kHz, tropical HF NAVTEX. Used in regions without dense MF coverage.
USCG HF voice and fax:
NMG, New Orleans. Voice on 4426, 6501, 8764, 13089, 17314 kHz. Fax on 4317.9, 8503.9, 12789.9 kHz.
NMC, Point Reyes. Voice on 4426, 8764, 13089, 17314 kHz. Fax on 4346, 8682, 12786, 17151.2 kHz.
Voice schedules vary by station, but the usual pattern is forecasts every 6 hours with offshore and high-seas synopses. Fax broadcasts run on a published rotation; many cruisers grab the analysis chart a couple of times a day for routing.
See also
The /ships-aircraft map for real-time vessel positions from AIS.
Marine VHF and HF gear also shows up on the license map under maritime coast and ship stations.