New price point for AIS class B+

[flyingnut40]

I think the reason the programming is controlled at the retail level is BECAUSE it is user programmable (with the CD) and the US wants that capability removed for whatever reason. The technique is flawed because if someone outside the US will give you the CD then you can do it yourself in the future. Aviom made reference in the manual that " programming Requires a GPS signal for timestamps purposes and that changes are only allowed over 30 days"
So where did THAT rule come from?

That unit above is similar price but NOT the latest protocol and no wifi. About $650 the cheapest with wifi so far......

[Tillsbury]

Originally Posted by Brian.D

So what happens if your boat has an 'unapproved' or 'expired' device? My guess probably nothing unless you are causing willful interference.

No offense, but I wouldn't buy anything from the Russian Federation. China, sometimes. Japan no problem.

Of all the devices it's illegal to use, I might try to avoid using one who's entire reason for existing is to tell the world your precise position.

[flyingnut40]

One has to wonder why the US is the only place that wont let you program your boat specifics into an AIS. Any chance the world has learned something from DSC radios that can only be programmed 2x before lock out causing people to use wrongly programmed radios in their boat......

Makes you wonder.......

[Cpt Pat]

Originally Posted by Coquina

eBay has always had AIS units for about that amount and they have all been uncertified and illegal to use in the USA and probably EU as well.

Yep. I just checked the FCC certification database:

https://apps.fcc.gov/oetcf/eas/repor...ericSearch.cfm

There are no applications on file that match the search criteria specified:
Applicant Name: Naviom

I suggest the OP check the device for an "FCC ID" number. If he can't find one, don't use it. The CG can get downright nasty if they have to hunt you down to stop and interfering device. If he can find one, run it in the search above to make sure it's legit.

BTW, you can get lots of useful info on any radio product by looking up its FCC ID. Internal photos, tests results, operating manuals, etc. You'll often find lab test result numbers that are very different from what the Marketing department wants you to see.

[Pete7]

Originally Posted by rslifkin

That's a Class B CSTDMA transceiver, not a B+ SOTMDA unit. Not the same thing at all.

True, other than a similar price. How important is the 5w of power compared to the B model with 2w? The New Horizons rocket that went to Pluto had a 10w transmitter, not bad reception given the huge distance to transmit back to earth.

So is the extra 3w for SOTDMA power really necessary?


Pete

[Kelkara]

Originally Posted by Pete7

True, other than a similar price. How important is the 5w of power compared to the B model with 2w? The New Horizons rocket that went to Pluto had a 10w transmitter, not bad reception given the huge distance to transmit back to earth.

So is the extra 3w for SOTDMA power really necessary?


Pete

for AIS to work, only one ship can be transmitting at a time. To do ensure this, every minute is divided up into about 2000 available time-slots. A CSTDMA device listens for an empty time-slot before making a transmission. In a crowded environment with 100s of ships transmitting, a CSTDMA device may never get an opportunity to transmit at all as all the time-slots will be taken. Another advantage of an SOTDMA device is that it will reserve a transmission time-slot for its next transmission.

[Tillsbury]

Originally Posted by Pete7

True, other than a similar price. How important is the 5w of power compared to the B model with 2w? The New Horizons rocket that went to Pluto had a 10w transmitter, not bad reception given the huge distance to transmit back to earth.

So is the extra 3w for SOTDMA power really necessary?


Pete

It's not about the range -- AIS class B has easily enough range if you have a decent aerial, the elevation is more important. What class B+ gives you is less likelihood that your signal will be lost in an extremely busy area because of so many other craft. This is possibly an advantage if you regularly sail in such areas. Where I am there are only a dozen boats within 100 miles transmitting AIS so it's not really something I've ever worried about.

On the other hand, if there really are hundreds of boats navigating in close proximity to you, I'd be tempted to rely almost entirely on eyeball navigation and would be almost totally ignoring the AIS. The ships that do matter on AIS (the big ones that are not going to get out of your way) are class A so they will appear on your chartplotter anyway whatever you have. The big guys are not going to be looking out for your AIS signal or not in that kind of environment, they'll be using radar since not all small boats have AIS anyway.

[Cpt Pat]

FYI: According to eBay: "Based in Russian Federation, naviom has been an eBay member since Jul 15, 2019"


It if doesn't play nice on the SOTDMA ad hoc network, it can wipe out service for quite a radius. I just noticed the OP is in Canada. Canada can be even more persnickety than the US about uncertified radio devices.

[Dsanduril]

Originally Posted by Brian.D

So what happens if your boat has an 'unapproved' or 'expired' device? My guess probably nothing unless you are causing willful interference.

For the most part I suspect you are right. The problem with AIS, in particular, is that you are transmitting your position, your identity, and every 6 minutes you transmit Message 24 which includes the AIS transmitter Equipment Vendor ID.

The USCG maintains a nationwide (well coast-wide anyway) active AIS monitoring network. It would take all of about 5 minutes to write a query against that database to extract every US MMSI being transmitted, in US waters, by an AIS transmitter with a vendor ID not approved in the US. Then you get the ticket in the mail. Personally, I'd rather not go down that road.

[Coquina]

Originally Posted by flyingnut40

One has to wonder why the US is the only place that wont let you program your boat specifics into an AIS. Any chance the world has learned something from DSC radios that can only be programmed 2x before lock out causing people to use wrongly programmed radios in their boat......

Makes you wonder.......

You can play all kinds of games with an easily changeable MMSI.
You can fish or crab where you aren't supposed to and magically watch your competitor get arrested for it because the Marine Traffic records show them doing it
You can play change the boat name between a full load of contraband one way and the empty trip the other...........nothing to see here officer
You can be a tanker instead of a J-22 on a night race and watch people get out of your way

[flyingnut40]

Good points..... returns are accepted and hoping that since the technology is very specialized that no one would even attempt to market such a device without jumping through the required hoops. Let's go with the theory that the FCC approval is done and we are waiting for the FCC and others to update their data base

[Cpt Pat]

Originally Posted by Coquina

You can play all kinds of games with an easily changeable MMSI.
You can fish or crab where you aren't supposed to and magically watch your competitor get arrested for it because the Marine Traffic records show them doing it
You can play change the boat name between a full load of contraband one way and the empty trip the other...........nothing to see here officer
You can be a tanker instead of a J-22 on a night race and watch people get out of your way

> You can play all kinds of games with an easily changeable MMSI.


Wrong. Not easily changeable.

That's precisely why the MMSI on Class B transponders can't be easily changed.

And the CG has other means of catching Bad Guys.

An off brand Russian transponder vendor ID will stand out like a flare on a dark night. Changing the vendor ID isn't trivial. Every reprogrammed a ROM? Probably not. You're describing actions that only a very determined sociopath would undertake. I hope anyone doing the above looks good in orange...

[pcmm]

Originally Posted by Pete7

True, other than a similar price. How important is the 5w of power compared to the B model with 2w? The New Horizons rocket that went to Pluto had a 10w transmitter, not bad reception given the huge distance to transmit back to earth.

So is the extra 3w for SOTDMA power really necessary?


Pete

Its more than the 3w difference. because its using SOTDMA, it communicates with Class A trancievers in a way that means it won't be ignored. SOTDMA trancievers can negotiate with Class A devices to get a transmit timeslot intstead of using just the Class B TDMA and hoping they don't get ignored because their transmit window lined up with another Class A that was transmitting.

[Coquina]

Thing is - if it goes nuts and causes problems, you will be the LAST to know, but the USCG will know right away and know exactly who did it.

[Coquina]

Originally Posted by Cpt Pat

> You can play all kinds of games with an easily changeable MMSI.


Wrong. Not easily changeable.

That's precisely why the MMSI on Class B transponders can't be easily changed.

And the CG has other means of catching Bad Guys.

An off brand Russian transponder vendor ID will stand out like a flare on a dark night. Changing the vendor ID isn't trivial. Every reprogrammed a ROM? Probably not. You're describing actions that only a very determined sociopath would undertake. I hope anyone doing the above looks good in orange...

USA spec ones are not easily changeable. The Chinese ones on Ebay you can do yourself