VHF with DSC, AIS, and GPS!

[Rustic Charm]

Originally Posted by MickBeth50

Rustic,

over the ocean - all airliners are monitoring. occasionally some may forget to, but this would be rare in my opinion. i fly over the ocean a lot.

over land it may not be as regular - as there are other things to listen to - like company freq or atis - or when on a short flight. but when you are in cruise an airliner is most probably listening to 121.5

m

cheers. wasn't aware of that.

[continuouswave]

Originally Posted by 4arch

For 99.5% of recreational boaters in the US, the BoatUS MMSI is adequate.

Then there are all the Michigan boaters on the Great Lakes, where a "foreign port" might be just a few miles away. (I think we're more than 0.5-percent of all USA boaters.) Although I live in Michigan, my boat spends more time in Canadian water than USA water.

The $160 fee charged by the FCC for a ship station license that includes an MMSI (good for ten years) is not too bad if you keep the same boat for ten years, but if you change boats you are supposed to get a new ship station license.

[Gi-Lo]

Hi all,

This is my first ever post on this forum, so please be gentle with me!

Firstly, as an Airline Pilot in Australia, I can confirm that we always keep our second VHF on 121.5 when not being used for anything else, and this is standard practice World wide. We occasionally hear distress beacons, and immediately report them, we would hear voice transmissions too. We only use "Numbers" (123.45) to chat when requested, and do not monitor it usually.

Now, I am in the market for a new Marine VHF, and this thread is the most recent thing I can find on the subject.

Like most opinions, I think that all of the current features plus the AIS Transceiver would be perfect. I accept that Separate GPS, AIS etc, may be a better option, but for the extra couple of hundred bucks, the Combo's will get me everything until I can afford to build my PERFECT system.
So here are a few questions that I am sure all of the experienced contributors to this Forum can answer for me.

1. Are there still no VHF/AIS TRANSCEIVERS available since this thread began??

2. If not, are the Units at the start of this thread still the most current on Offer?

3. If so, which of them is the best?

4.If the unit has AIS and NMEA 2000. will it display the AIS targets on any other Display, for example the RAYMARINE i70 which is AIS compatible?

5. If I later added an AIS TRANSCEIVER to the System, can I switch off the AIS function of the VHF..... or do I indeed need to do this?

6. If a add a dedicated GPS to the system, do I need to disable the GPS in the VHF, or how would the system prioritize which GPS signal to use for SOG COG etc?

And Finally, the Australian dollar is at a long time low against the US dollar, so it's a perfect time for all of our US friends to come and visit our wonderful country. If you don't have time to sail here..... then Jump on a plane, and keep me in a job

[CharlzO]

Originally Posted by Gi-Lo

1. Are there still no VHF/AIS TRANSCEIVERS available since this thread began??

2. If not, are the Units at the start of this thread still the most current on Offer?

3. If so, which of them is the best?

4.If the unit has AIS and NMEA 2000. will it display the AIS targets on any other Display, for example the RAYMARINE i70 which is AIS compatible?

5. If I later added an AIS TRANSCEIVER to the System, can I switch off the AIS function of the VHF..... or do I indeed need to do this?

6. If a add a dedicated GPS to the system, do I need to disable the GPS in the VHF, or how would the system prioritize which GPS signal to use for SOG COG etc?

And Finally, the Australian dollar is at a long time low against the US dollar, so it's a perfect time for all of our US friends to come and visit our wonderful country. If you don't have time to sail here..... then Jump on a plane, and keep me in a job

I can't answer every question, but for the experiences I have had:

1) I haven't seen a VHF with a transceiver just yet, probably due to the additional cost, might push it out of the "normal" budget for the target audience.

2) I haven't seen a replacement to the 2200 yet, but that's not to say something isn't coming for Springtime

4) I have mine outputting to a Standard Horizon cpn700i chartplotter, and it does indeed put my AIS targets onto the screen of the plotter. I would imagine it would do the same with most any compatible unit, given it's wired per instructions for the in/outputs.

5) Not 100% sure if you need to turn it off, but you may need to create an allowance on the receiver to not pick up the signal you're putting out yourself. But, if you have a dedicated transceiver, you may decide to just use that 100% for the AIS functions anyway.

6) Not sure how much it prioritizes, but in my plotter, if memory serves, I have the option to determine if I'm using the GPS input from the radio or not, so I imagine most units would give the option as well, which signals to use, and so forth. Since my plotter has it built in anyway, I have it set to use it's internal GPS instead, and the only thing the radio is sending to it, is the AIS data.

Hope it helps some!

[4arch]

Originally Posted by CharlzO

1) I haven't seen a VHF with a transceiver just yet, probably due to the additional cost, might push it out of the "normal" budget for the target audience.

I really hope that's not the reason such a product is being held back. By the time one buys a VHF radio, AIS transceiver, antenna splitter, and all the needed installation accessories it can easily add up to $1K or more. An all-in-one VHF radio/AIS transceiver priced even in the $900-999 range would represent a good value. There are often a lot of electronics releases announced at the Miami Boat Show, which is coming up in mid-February. I keeping my fingers crossed that such a device will be announced for release this spring (though not getting my hopes up too high). I'd love to add AIS transceive capability to my boat in 2015 and an all-in-one is the way I want to do it.

[carstenb]

Originally Posted by 4arch

I really hope that's not the reason such a product is being held back. By the time one buys a VHF radio, AIS transceiver, antenna splitter, and all the needed installation accessories it can easily add up to $1K or more. An all-in-one VHF radio/AIS transceiver priced even in the $900-999 range would represent a good value. There are often a lot of electronics releases announced at the Miami Boat Show, which is coming up in mid-February. I keeping my fingers crossed that such a device will be announced for release this spring (though not getting my hopes up too high). I'd love to add AIS transceive capability to my boat in 2015 and an all-in-one is the way I want to do it.

There are several reasaons for not incorporating the AIS into the VHF.
1- AIS requires its own dedicated GPS (can't share)
2- If incorporated, the VHF would have to either incorporate a separate antenna plug (if you want a dedicated antenna for the AIS) or incorporate a splitter.

The above would make the unit much bigger and therefore difficult to mount

[Jman]

Originally Posted by carstenb

There are several reasaons for not incorporating the AIS into the VHF.

1- AIS requires its own dedicated GPS (can't share)

2- If incorporated, the VHF would have to either incorporate a separate antenna plug (if you want a dedicated antenna for the AIS) or incorporate a splitter.



The above would make the unit much bigger and therefore difficult to mount

1. That is fine, there are plenty of vhf radios, including handhelds with built in gps.
2. Not so. The problem with standalone radios and ais, is you need a pretty expensive splitter, because the splitter needs to intelligently know when the talk button on the vhf has been pressed vs. the standard transmissions coming out of the ais unit. Would be much easier to build that into one unit.


Sent from my iPad using Cruisers Sailing Forum

[toddedger]

I installed the Icom unit hooked up to a Raymarine NMEA 2000 network and it was really nice. There are a few quirks, like I wish proximity alarms would not trigger unless a vessel is actually moving, not at a dock pointed at me. One downside is the Icom remote mic does not show AIS targets on the display.

However on my personal sailboat I use an older Standard Horizon with a remote mic in the cockpit. The new SH unites display AIS info on the remote mic, but they don't output data in NMEA 2000, only in 0183. Having the AIS info on the remote mic is a big plus for me, but according to what I read from Raymarine not all AIS info will show on the plotter if it comes in over 0183 instead of the 2000 standard. I asked Standard Horizon if they were going to add NMEA 2000 to their VHF with AIS and they said they had no future plans to add it to their VHF's.

So that is why I have not upgraded my VHF yet. I'm waiting for the whole solution to be available. Does anyone have any experience with the Standard Horizon AIS integrated into their Chartplotters?

[Gi-Lo]

Originally Posted by toddedger

I installed the Icom unit hooked up to a Raymarine NMEA 2000 network and it was really nice. There are a few quirks, like I wish proximity alarms would not trigger unless a vessel is actually moving, not at a dock pointed at me. One downside is the Icom remote mic does not show AIS targets on the display.

However on my personal sailboat I use an older Standard Horizon with a remote mic in the cockpit. The new SH unites display AIS info on the remote mic, but they don't output data in NMEA 2000, only in 0183. Having the AIS info on the remote mic is a big plus for me, but according to what I read from Raymarine not all AIS info will show on the plotter if it comes in over 0183 instead of the 2000 standard. I asked Standard Horizon if they were going to add NMEA 2000 to their VHF with AIS and they said they had no future plans to add it to their VHF's.

So that is why I have not upgraded my VHF yet. I'm waiting for the whole solution to be available. Does anyone have any experience with the Standard Horizon AIS integrated into their Chartplotters?

Wow, thanks so much for this post, I was 1 click away from buying the GX2200, but my system is NMEA 2000, so I would have been disappointed. Shame, I found the unit for $299!

The links at the start of this thread for the ICOM unit, don't actually seem to state that the unit has GPS, I Am assuming it must have inbuilt GPS?

[Gi-Lo]

Originally Posted by Gi-Lo

Wow, thanks so much for this post, I was 1 click away from buying the GX2200, but my system is NMEA 2000, so I would have been disappointed. Shame, I found the unit for $299!

The links at the start of this thread for the ICOM unit, don't actually seem to state that the unit has GPS, I Am assuming it must have inbuilt GPS?

So after some more reading it appears that the ICOM does not have inbuilt GPS, So now I learn something else..... You cannot Edit/Delete your posts on this Forum after they have been up for 20 mins....... Wow

So I still can't find an VHF AIS (inbuilt)GPS NMEA 2000 unit......

[CharlzO]

Originally Posted by toddedger

So that is why I have not upgraded my VHF yet. I'm waiting for the whole solution to be available. Does anyone have any experience with the Standard Horizon AIS integrated into their Chartplotters?

I mentioned mine a few posts back, but I have their 2200 hooked up with their cpn700i chartplotter. Puts the AIS targets on the display just fine, and I've had no issues with the hookup. Took me a few readings of the wiring diagrams back and forth to make sure I was hooking it right (I believe the VHF instructions had it laid out perfectly, but I'd have to open the manual up to be sure). It's really the only thing I have linked between them, as the chartplotter has it's own GPS to run it's goodies off of, I just wanted the AIS from the radio linked, and it does that just fine.

Note: Just looked up the PDF manuals, I was using the page 18 on the radio book, and page 160 on the chartplotter (I have the 525 fish finder as well) - matched the NMEA+ and - to what the radio and plotter's wires were.

[4arch]

Originally Posted by carstenb

There are several reasaons for not incorporating the AIS into the VHF.
1- AIS requires its own dedicated GPS (can't share)
2- If incorporated, the VHF would have to either incorporate a separate antenna plug (if you want a dedicated antenna for the AIS) or incorporate a splitter.

The above would make the unit much bigger and therefore difficult to mount

I don't see these as insurmountable engineering challenges. The GX2200 already has everything an all-in-one would need except AIS transceiver (instead of receiver only) and NMEA 2000 connectivity. I don't see how adding those capabilities would significantly increase the size. Also, as far as I am aware, there's no standardized form factor or sizing for VHF radios. If an all-in-one device needs to be somewhat larger, it's a price I'm happily willing to pay.

Originally Posted by toddedger

I asked Standard Horizon if they were going to add NMEA 2000 to their VHF with AIS and they said they had no future plans to add it to their VHF's.

I wouldn't take such a statement at face value as companies usually hold product lineup changes close to the vest until an "official" announcement date. As recently as a few years ago it was reasonable to make the argument that the low and middle end of the marine electronics market didn't need and wasn't demanding NMEA 2000 but now the awareness of it is much greater and it's starting to appear even on entry level products.

[transmitterdan]

I don't see any technical reason why a VHF radio could not incorporate full AIS class B transceiver functionality. I don't know this for sure but I suspect the reason there isn't one yet is a combination of the market size and the regulatory hurdles needed to gain approval to market the product. It takes time and money to get the approvals from EU, US and other countries. The cost can be quite high so there has to be a sizable market before anyone will undertake the process. It also might take some innovative rule interpretations to get it approved since the radio, DSC and AIS would have to time share in a cost effective design.

Regarding the NMEA0183 vs. NMEA2000 difference issue I suspect that is not as simple as it sounds. There is no reason NMEA0183 cannot provide full AIS functionality. If it does not the software at one end or the other is most likely to blame not the interface itself.

[continuouswave]

Originally Posted by transmitterdan

I don't see any technical reason why a VHF radio could not incorporate full AIS class B transceiver functionality.

Assuming a VHF Marine Band DSC Class-D radio and an AIS Class-B transponder were combined, and assuming they used a common antenna, there are some technical problems:

--antenna would need to be broader in VSWR bandwidth than usual antennas

--for CLASS-B AIS, the transponder would need to transmit as often as every 30-seconds if moving at high speeds;

--when AIS was transmitting, the communication radio could not be transmitting on DSC or voice, or effectively receiving on DSC or voice

--when the communication radio was transmitting, the AIS could not be receiving or transmitting;

If we assume separate antennas for the communication radio and the AIS transponder, most of those problems go away, but one would need some physical separation between antennas in order to prevent the AIS transmitter from causing too much desensitizing of the communication receiver and vice versa.

[transmitterdan]

Class B can skip time slots as needed. Many installations use splitters and have the same issues but it works ok.

VSWR is not as big an issue as it might seem. A VSWR of 2:1 is still about 90% efficient. 3:1 is 75% efficient. These are transmit related values ignoring coax loss.