International frequencies

[paulears]

You guys are overthinking this. The vessel infrastructure that the licensed radio operators use for short to long distance comms are closely controlled for obvious reasons. Internal short range comms are rarely an issue because the range is restricted by distance and obstacles. The only areas where interference with other users is likely are when they are in port. So docks full of containers is probably not a problem, but I guess a shoe shop could find talking to the stock room occasionally difficult, but CTCSS stops the interference being heard. Transmissions from hand helds are sporadic. Scanner users have difficulty even finding ship board hand held traffic unless they are close, for signal strength and short to time reasons. I suspect it’s a total non-issue, and invisible to shore and vessel users, who might at worse, just not occasionally get an answer. That’s normal anyway?

people from the US take walkie talkies on their skiing holidays, as do Brits, and while they shouldn’t, it’s rarely a big problem, if a problem at all.

 

[ecps92]

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.

All depends on your market Still used in the Boston area, along with some Part 90 that one station decided to go with

 

[ecps92]

You guys are overthinking this. The vessel infrastructure that the licensed radio operators use for short to long distance comms are closely controlled for obvious reasons. Internal short range comms are rarely an issue because the range is restricted by distance and obstacles. The only areas where interference with other users is likely are when they are in port. So docks full of containers is probably not a problem, but I guess a shoe shop could find talking to the stock room occasionally difficult, but CTCSS stops the interference being heard. Transmissions from hand helds are sporadic. Scanner users have difficulty even finding ship board hand held traffic unless they are close, for signal strength and short to time reasons. I suspect it’s a total non-issue, and invisible to shore and vessel users, who might at worse, just not occasionally get an answer. That’s normal anyway?

people from the US take walkie talkies on their skiing holidays, as do Brits, and while they shouldn’t, it’s rarely a big problem, if a problem at all.

Not any overthinking

CTCSS only blocks casual users from hearing, it does cause interference and with the right tone, can trip GMRS Repeaters etc

457 input on a cruise ship with a 467 output can be the input 467 to a US GMRS Repeater with a 462 output

 

[speedway_navigator]

A friend of mine and ECSP32 who is in the cruise ship industry and a fellow radio geek said they get a license from the country the ship was built in, not each country they visit. Co-channel RFI is a problem due to the limited number freqs available. Some of the ITU freqs are off limits in some countries which makes it harder.

 

[paulears]

Not any overthinking

CTCSS only blocks casual users from hearing, it does cause interference and with the right tone, can trip GMRS Repeaters etc

457 input on a cruise ship with a 467 output can be the input 467 to a US GMRS Repeater with a 462 output

Yes - I get it, but If the repeater is in the docks, and there is a conversation at the same time - in reality is that's pretty bad luck isn't it? The exact same frequency in the exact same area. I take the point that it could, but a few Watts of RF inside a ship, or even on the decks, is pretty unlikely in the great scheme of things to be an issue. Look at the thousands of Baofeng 888 walkie talkies that had frequencies in them all over the place - real issues were surprisingly rare. The 'test' frequencies occasionally do things? Ailunce have one that is the local hospital's radio pager channel - so people turning them on often do indeed get interesting messages, but transmitting doesn't do anything and the users are unaware.

It's pretty unlikely that there will be real problems of this type - in the 40+ years our local repeater in the docks has been working, I've never noticed any issues with all the foreign vessels that moor up alongside it (it is on a 200ft tall grain silo)

 

[ecps92]

Yes - I get it, but If the repeater is in the docks, and there is a conversation at the same time - in reality is that's pretty bad luck isn't it? The exact same frequency in the exact same area. I take the point that it could, but a few Watts of RF inside a ship, or even on the decks, is pretty unlikely in the great scheme of things to be an issue. Look at the thousands of Baofeng 888 walkie talkies that had frequencies in them all over the place - real issues were surprisingly rare. The 'test' frequencies occasionally do things? Ailunce have one that is the local hospital's radio pager channel - so people turning them on often do indeed get interesting messages, but transmitting doesn't do anything and the users are unaware.

It's pretty unlikely that there will be real problems of this type - in the 40+ years our local repeater in the docks has been working, I've never noticed any issues with all the foreign vessels that moor up alongside it (it is on a 200ft tall grain silo)

a few watts are 15 stories high or more, will/does have impacts. RF is not locked inside the metal ship.

Also the CCR's on illegal channels have been known, to cause harmful interference, just those who are dealing with it keep it close-to-the-vest and have no need of it going outside (sharing with Hobby World) those who have tracked down the offenders and worked with the FEDERAL authorities to clean up the airwaves of the CCR's - Yes the Horse is out of the barn, but those who are harmed by the interference can and are doing things.

 

[paulears]

You're absolutely right - just never actually found it a problem, and most people with handhelds struggle to do more than a very short distance. Of course, with just the wrong frequency, just the wrong tone, and time aligning, it can be very bad - but I find no data here from official sources to indicate we have any problem with visiting US ships.

 

[ecps92]

You're absolutely right - just never actually found it a problem, and most people with handhelds struggle to do more than a very short distance. Of course, with just the wrong frequency, just the wrong tone, and time aligning, it can be very bad - but I find no data here from official sources to indicate we have any problem with visiting US ships.

Does the UK have allocations in the GMRS frequencies 462.5500-462.7250 and 467.5500-467.7250 ?

Also, don't think U.S. since most of the ships from the US Companies are not US Flagged.

Cruise Ship Registry, Flags of Convenience, Flag State Control | CruiseMapper

Cruise ship registry/registration, what is flag state control, flags of convenience, list of cruise ships sailing under foreign flags, money, pirates, fun.

www.cruisemapper.com

 

[AM909]

Do any of the Liberian-flagged ships ever visit Liberia, even during construction? I would expect either the "home port" of a ship, or the domicile of the operating company, to be where handheld radios are procured and licensed. Pretty sure I had one of those customers in SoCal at one point many years ago.

 

[paulears]

Does the UK have allocations in the GMRS frequencies 462.5500-462.7250 and 467.5500-467.7250 ?

Also, don't think U.S. since most of the ships from the US Companies are not US Flagged.

Cruise Ship Registry, Flags of Convenience, Flag State Control | CruiseMapper

Cruise ship registry/registration, what is flag state control, flags of convenience, list of cruise ships sailing under foreign flags, money, pirates, fun.

www.cruisemapper.com

We do indeed - 460-470 is one of our busiest UHF chunks of spectrum - for business and even data. Now a mix of analogue and digital, of course. Watching on a cellular monitor, you see a big ship arrive - no idea of registry, and then the cellular network suddenly fill up with things like Verizon and other US cellular carriers as the people disembark. It's also the only time us Brits experience US GMRS with the families talking to their kids on radios totally illegal to use here, but while the local hams and scanner folk are interested, it really causes little impact, and as I mentioned earlier, with CTCSS, the real users never even notice their channels are being used. I suppose a few PTT presses bring no response, but the users are blissfully unaware - both the official Brit users and the US visitors. Since our Police, Fire and Ambulance went secure years back, we have no vital comms services in our common bands, so our Government considers them unprotected in general. It actually works fine in practice. We have two busy ports within ten miles of here, and ship wise, the worst is the summer month VHF lifts where our coastal radio services use common channels, separated by distance - so 12, then 14, then 12, then 14 around the coast. This is probably the only 'interference' issue I hear mentioned nowadays. For business users, we have two choices - what is called technically assigned channels - the Government allocate you a frequency, geographically cleared. No sharing anywhere other than busy cities, and that's getting less now. Other than that, people use a cluster of low band VHF, high band VHF and UHF channels - probably 12 or so in total. The licence for these doesn't even ask the users which one they use? Most people just put all the UHF ones in their radios as multiple channels. With CTCSS, it works really well.

Having dealt with marine radio for a long time now, ship flag and nationality rarely mean anything. Our local college teach ship captaincy - so lots of our oil/gas/wind vessels are flagged from countries I don't even know, crewed with a multitude of random national, permanently berthed in the UK with an Indian captain - the biggest customers of the local college.

I get called out to fix all kinds of radio comms in this area, and it's very rare for co-channel interference to ever be the cause. I really think that while the issues in this topic are possible, in real life - one countries system doesn't impact another that much, if at all. US holiday resorts, hot and cold that get UK visitors, also get families with our PMR446 radios in their luggage. Simplex, at the bottom of the 446MHz band - does this cause you issues you've heard of?

 

[mmckenna]

Issue here in the USA is many large port cities may have several repeaters on each GMRS pair, and some of those repeaters may have many active PL tones for different users. When this issue has happened in the past, the shipboard repeaters had their outputs on the GMRS repeater inputs. If the PL tones matched, everyone got to share in the fun.

I do recall the FCC getting involved back in the 1990s, but only to the point of talking to the ships master and having the switch to other channels that were legal to use in the USA.

So, not a zero impact issue, but not a huge deal either. Since the ships are transient, the issue would go away as soon as they left, often before they could be tracked down.

For GMRS repeater owners near large ports, staying of the three lower GMRS pairs would be best, but not always an option.

 

[ecps92]

Issue here in the USA is many large port cities may have several repeaters on each GMRS pair, and some of those repeaters may have many active PL tones for different users. When this issue has happened in the past, the shipboard repeaters had their outputs on the GMRS repeater inputs. If the PL tones matched, everyone got to share in the fun.

I do recall the FCC getting involved back in the 1990s, but only to the point of talking to the ships master and having the switch to other channels that were legal to use in the USA.

So, not a zero impact issue, but not a huge deal either. Since the ships are transient, the issue would go away as soon as they left, often before they could be tracked down.

For GMRS repeater owners near large ports, staying of the three lower GMRS pairs would be best, but not always an option.

and in the recent (past 5-10) years, I've noticed more (on the CARGO not Cruise) that the Captain can turn on/off the repeater(s) and direct his users to another channel which may alleviate the interference (both ways - ships experience it too)

 

[paulears]

I've been doing some research and have discovered a few things - there are International Regulations that control the licencing of radios used on board. This means that the country to which the vessel is flagged is the only country who can licence the vessel. OFCOM, here in the UK cannot issue any licences to foreign registered ships, even if they spend all their lives in UK waters.

The UK UHF marine channels are these - and would be used on board UK flagged ships worldwide. Licenced under UK authority.
457.5254MHz
467.5254MHz
457.5504MHz
467.5504MHz
457.5754MHz
467.5754MHz
457.53755 MHz
457.56255MHz
467.53755MHz
467.56255MHz
They're also authorised to us two airband frequencies too:
121.5, 123.1 MHz - one the International VHF guard channel, and the other secondary to it.

What the documents I have found do not seem to cover is how the ships equipment, covered under a UK licence, operates in a foreign port. UK regs are clear - a ship anything other than a UK flagged one cannot have a UK radio licence, so how would a UK ship moored in say, Florida be legal in the US, a US one would not be legal here in the UK. Perhaps the international waters thing doesn;t apply. Similar to the radio systems used in embassies worldwide.

 

[mmckenna]

so how would a UK ship moored in say, Florida be legal in the US, a US one would not be legal here in the UK. Perhaps the international waters thing doesn;t apply. Similar to the radio systems used in embassies worldwide.

It is in the ITU agreements, specifically designed to handle things like ships and aircraft that travel internationally.

 

[paulears]

So, the possible interference issues are moot then? Foreign flagged vessels, moored in ports around the world may or may not cause interference with impunity? Good job they don't cause much in the way of issues.

 

[mmckenna]

So, the possible interference issues are moot then? Foreign flagged vessels, moored in ports around the world may or may not cause interference with impunity? Good job they don't cause much in the way of issues.

No, not moot. The ITU specifically mentions this, and they put some requirements on the radio operator to understand this.

But, yes, interference happens.

 

[AM909]

...
The UK UHF marine channels are these - and would be used on board UK flagged ships worldwide. Licenced under UK authority.
457.5254MHz
467.5254MHz
457.5504MHz
467.5504MHz
457.5754MHz
467.5754MHz
457.53755 MHz
457.56255MHz
467.53755MHz
467.56255MHz
...

I'm guessing those spurious digits at the end of the frequencies were footnotes in the document they were copied from? E.g., "457.5254MHz" should be "457.525 MHz", "457.53755 MHz" should be "457.5375 MHz", etc..

 

[mmckenna]

I'm guessing those spurious digits at the end of the frequencies were footnotes in the document they were copied from? E.g., "457.5254MHz" should be "457.525 MHz", "457.53755 MHz" should be "457.5375 MHz", etc..

No, they are for 6.25KHz very narrow digital channels.

 

[ecps92]

No, not moot. The ITU specifically mentions this, and they put some requirements on the radio operator to understand this.

But, yes, interference happens.

Correct, such as channel x, y and z should not be used in ABC, but could be used in CDA

but who reads rules Heck, the input and outputs are clearly defined, yet we find them as reversed pairs sometimes.

 

[ecps92]

I've been doing some research and have discovered a few things - there are International Regulations that control the licencing of radios used on board. This means that the country to which the vessel is flagged is the only country who can licence the vessel. OFCOM, here in the UK cannot issue any licences to foreign registered ships, even if they spend all their lives in UK waters.

The UK UHF marine channels are these - and would be used on board UK flagged ships worldwide. Licenced under UK authority.
457.5254MHz
467.5254MHz
457.5504MHz
467.5504MHz
457.5754MHz
467.5754MHz
457.53755 MHz
457.56255MHz
467.53755MHz
467.56255MHz
They're also authorised to us two airband frequencies too:
121.5, 123.1 MHz - one the International VHF guard channel, and the other secondary to it.

What the documents I have found do not seem to cover is how the ships equipment, covered under a UK licence, operates in a foreign port. UK regs are clear - a ship anything other than a UK flagged one cannot have a UK radio licence, so how would a UK ship moored in say, Florida be legal in the US, a US one would not be legal here in the UK. Perhaps the international waters thing doesn;t apply. Similar to the radio systems used in embassies worldwide.

Air Band - yes as well, due to most of the larger ships have a Helipad