International frequencies

[Hiram1717]

Hello everyone!

Not sure if I posted this in the right section.

How is it that cruise ships and yacht crew have radios and travel internationally without any issue in frequencies? How does that work?

 

[nd5y]

Maybe they use VHF marine radios.
Maybe they use 457/467 MHz on-board UHF radios.
Maybe they don't care about illegal operation in a country's territorial waters and use CCRs with random frequencies.

 

[ecps92]

Hello everyone!

Not sure if I posted this in the right section.

How is it that cruise ships and yacht crew have radios and travel internationally without any issue in frequencies? How does that work?

If the CCR's they don't give a damn. We've had some found using the local News Media 450/455 channels and causing interference.

IF VHF Marine as Tom says they are ITU recognized

Beyond that there are two sets of 457/467 pairings available, one for the US the others generally recognized, but
those visits are such short term, no one actually tracks down the culprits

so many rabbit holes to dive down without knowing much more

 

[chief21]

I don't think there is much planning or coordination involved. There are often reports of interference in the vicinity of port cities caused by vessels registered in other countries.

 

[mmckenna]

How is it that cruise ships and yacht crew have radios and travel internationally without any issue in frequencies? How does that work?

International Telecommunications Union is the worldwide body that handles this stuff. ITU: Committed to connecting the world

Services like Marine VHF and UHF are assigned worldwide and most countries honor another countries license. That makes life easier for a ship or aircraft that travels between countries, and helps radio services that work across the world (like Shortwave) all get along.

 

[jwt873]

Are you talking about ship to ship radio or crew communications on board?

For ship to ship, there are VHF frequencies used internationally. International VHF Marine Radio Channels and Frequencies | Navigation Center

For on board crew to crew comms, as nd5y points out, they do use in the 450 to 460 MHz range. A quick search shows this chart someone cobbled up for international cruise lines - https://www.scanmaritime.com/frequencies.htm

 

[ecps92]

Are you talking about ship to ship radio or crew communications on board?

For ship to ship, there are VHF frequencies used internationally. International VHF Marine Radio Channels and Frequencies | Navigation Center

For on board crew to crew comms, as nd5y points out, they do use in the 450 to 460 MHz range. A quick search shows this chart someone cobbled up for international cruise lines - https://www.scanmaritime.com/frequencies.htm

Cobble we do with much assistance from members here

 

[jwt873]

That was quite a bit of work.. I guess cobbled wasn't the best descriptor...

 

[krokus]

I presume that the cruise ships use a setup similar to the system used on the aircraft carrier I was stationed on. There was "leaky coax" run throughout the ship, which allowed coverage everywhere, and an external whip for the weather decks. (The whip was shutdown while in port, to avoid conflicts with other ships/systems. This lesson was learned when a battle group cellular system was installed.)

 

[ecps92]

That was quite a bit of work.. I guess cobbled wasn't the best descriptor...

just having some fun with you, no harm/no foul - and appreciate the sharing of the link to the pages

 

[ecps92]

I presume that the cruise ships use a setup similar to the system used on the aircraft carrier I was stationed on. There was "leaky coax" run throughout the ship, which allowed coverage everywhere, and an external whip for the weather decks. (The whip was shutdown while in port, to avoid conflicts with other ships/systems. This lesson was learned when a battle group cellular system was installed.)

The only thing the cruise ships shut down is "supposed" to be the on-board cellular

And even with DMR, as with PL/DPL the ker-chunking that can/does occur when multiple ships are in port is a nightmare
with 457/467 or 467/457 pairings no standard for in/out or out/in

 

[Hiram1717]

Are you talking about ship to ship radio or crew communications on board?

For ship to ship, there are VHF frequencies used internationally. International VHF Marine Radio Channels and Frequencies | Navigation Center

For on board crew to crew comms, as nd5y points out, they do use in the 450 to 460 MHz range. A quick search shows this chart someone cobbled up for international cruise lines - https://www.scanmaritime.com/frequencies.htm

With onboard communication how is it that they don’t interfere with frequency in the country they visit?

 

[Hiram1717]

Are you talking about ship to ship radio or crew communications on board?

For ship to ship, there are VHF frequencies used internationally. International VHF Marine Radio Channels and Frequencies | Navigation Center

For on board crew to crew comms, as nd5y points out, they do use in the 450 to 460 MHz range. A quick search shows this chart someone cobbled up for international cruise lines - https://www.scanmaritime.com/frequencies.htm

With onboard communication how is it that they don’t interfere with frequency in the country they

 

[ecps92]

With onboard communication how is it that they don’t interfere with frequency in the country they visit?

They can and do cause interference, especially here in the US on GMRS (467)

 

[mmckenna]

With onboard communication how is it that they don’t interfere with frequency in the country they

The onboard UHF systems use internationally allocated frequencies that are ~generally~ agreed upon world wide. *

* One exception is that some of the on board UHF systems use frequencies utilized by GMRS repeater inputs here in the USA. Ships are not supposed to use those channels when in US waters. But, it happens. Ship repeater on GMRS input, GMRS users get upset, ships get upset, everybody gets upset, then the ship moves on….

 

[Hiram1717]

The onboard UHF systems use internationally allocated frequencies that are ~generally~ agreed upon world wide. *

* One exception is that some of the on board UHF systems use frequencies utilized by GMRS repeater inputs here in the USA. Ships are not supposed to use those channels when in US waters. But, it happens. Ship repeater on GMRS input, GMRS users get upset, ships get upset, everybody gets upset, then the ship moves on….

sorry if you already answered this question but I am so interested in how this works. I have gone on multiple cruises I have brought my grms radios and never heard the crew transmit. Do they have a way that, the frequencies they are using are only heard through their radios?

 

[mmckenna]

sorry if you already answered this question but I am so interested in how this works. I have gone on multiple cruises I have brought my grms radios and never heard the crew transmit. Do they have a way that, the frequencies they are using are only heard through their radios?

They are not using GMRS. The ITU has some UHF frequency allocations that are assigned worldwide for shipboard communications systems. That includes shipboard repeaters. Some of the upper frequencies align with 3 of the GMRS repeater inputs in the USA. They also have some options for narrower bandwidth where one of the frequencies aligns with one of the 467 FRS channels.

You won't hear them on your GMRS radio because the frequencies in question fall on GMRS repeater INPUT frequencies. Your GMRS radio won't hear that. It might hear the splinter channel that aligns with FRS.

https://www.itu.int/dms_pubrec/itu-r/rec/m/R-REC-M.1174-4-201910-I!!PDF-E.pdf

They may or may not be using CTCSS/DCS, or in some cases, digital modulation, so they would not necessarily hear a user on GMRS/FRS.

 

[AM909]

FWIW, the shipboard repeater pairings for the US are 10.225 MHz splits, as shown in 47 CFR 90.35(c)(60)(iii), moving the inputs up above the US GMRS inputs. The international split is only 10 MHz (as linked by MMc above), so they conflict with the US GMRS inputs.

 

[ecps92]

FWIW, the shipboard repeater pairings for the US are 10.225 MHz splits, as shown in 47 CFR 90.35(c)(60)(iii), moving the inputs up above the US GMRS inputs. The international split is only 10 MHz (as linked by MMc above), so they conflict with the US GMRS inputs.

many of the same channels conflict with other users too, the ole fast food headsets, GMRS inputs etc

 

[speedway_navigator]

If the CCR's they don't give a damn. We've had some found using the local News Media 450/455 channels and causing interference.

Last time I scanned for those part 74 freqs I came up empty, I figured the intercom and IFB stuff is IP or phone based now.