Is AIS in the house?

Another thread that has considerable about AIS and the Standard Horizon 2150.

http://www.c-brats.com/viewtopic.php?t=20861&highlight=

Thanks Bob, you have been very thorough. I do appreciate your help here. Without, I would have not had as effective system. I have been trying to avoid putting another antenna up. As it looks now, I am going to pull the splitter out from between the Ray218 VHF and AM/FM and put the 218 directly to the 8ft Commrod. Then put in the Vespar splitter between the Standard Horizon 2150 and the WatchMate AIS. That side will go to the Shakespeare 4ft that is mounted on a 24" riser, so I will continue to use a marine vhf tuned antenna there. The AM/FM will plug into the Vespar splitter on it's own dedicated bnc port and gets a receiver gain as well.

I have considered Putting the SH 2150 onto the Commrod to separate it totally from the AIS (I am using the AIS receive on it to go to the RayMarine Classic 120 - providing AIS contact points onto the plotter display.) It is also the radio I usually use for contacts other than on 16. This arrangement would eliminate the plotter AIS display pausing when the vhf is used or when the Watchmate AIS bursts are transmitted.

Another consideration: the Standard Horizon will see the active AIS transmitting from it's own position and on the same MMSI and will put that on the plotter as an AIS contact, and that will generate a "Dangerous Target" warning ..... constantly. NOT GOOD. So, the fix is in. Standard Horizon's newer 2150's have a setting to filter that signal from it's own MMSI out. The Good Part is that my (And currently any 2150 under 3 years old,) can be sent back to Standard Horizon, and they will put that filter in and activate it.

That little tidbit came from MartyK at Rodger's Marine in Portland.

So the radio has to come out and go for a trip, but it will be better for it.
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Harvey
SleepyC:moon
 
I must qualify my last post. In the free version there is a 5 min refresh delay but there are pay versions with much less delay and more info. I don't have any experience with the pay versions. There is a companion app called IAIS the transmits your (Cell Phone's) position and it will show your position on real AIS receivers as well as the Marine Traffic app. It is also free and works well. We have used it for over 1 year.
 
Alexander,
I may have not made my point clear. It is not the lack of cell service of your boat. The "holes" in the various apps, are places where there are no volunteer listeners. If you watch boats in many areas, especially in the less populated areas of the ICW--they just don't have any AIS readings for long segments of the coast line. That is because there are not any people who have put in an AIS receiver, antenna and who dedicate a computer to sending the AIS reports to the server for the APP.

Regards,
 
Alexander":wpex1r97 said:
I must qualify my last post. In the free version there is a 5 min refresh delay but there are pay versions with much less delay and more info. I don't have any experience with the pay versions. There is a companion app called IAIS the transmits your (Cell Phone's) position and it will show your position on real AIS receivers as well as the Marine Traffic app. It is also free and works well. We have used it for over 1 year.
Click to expand...

As I understand it (for the Android version anyway), the IAIS app (mAIS for Android) sends your pseudo AIS information to the Marine Traffic website. It does this using the phone GPS and requires a live internet connection to operate. Your "AIS" information will only appear on the website version of the Marine Traffic AIS display. Boats using "real" onboard AIS receivers will not see you unless they also happen to be watching the website.

If your phone does don't have an internet connection, you will not appear on the web site display.

While this is an interesting app, it is not something that really replaces a true AIS system IMO.
 
ssobol":1cr2bqh4 said:
Alexander":1cr2bqh4 said:
I must qualify my last post. In the free version there is a 5 min refresh delay but there are pay versions with much less delay and more info. I don't have any experience with the pay versions. There is a companion app called IAIS the transmits your (Cell Phone's) position and it will show your position on real AIS receivers as well as the Marine Traffic app. It is also free and works well. We have used it for over 1 year.
Click to expand...

As I understand it (for the Android version anyway), the IAIS app (mAIS for Android) sends your pseudo AIS information to the Marine Traffic website. It does this using the phone GPS and requires a live internet connection to operate. Your "AIS" information will only appear on the website version of the Marine Traffic AIS display. Boats using "real" onboard AIS receivers will not see you unless they also happen to be watching the website.

If your phone does don't have an internet connection, you will not appear on the web site display.

While this is an interesting app, it is not something that really replaces a true AIS system IMO.
Click to expand...

ssobol,

I agree that it does not replace a true active AIS. It may work in areas where there is good phone coverage but again, it is not to be relied on for navigation and safety. There is too much time delay, too many gaps in coverage and too little reliability.

Harvey
SleepyC:moon
 
Today true AIS receivers are inexpensive--and the cost of AIS B has come down very significantly--less than radar. It is not for everyone. But if you are in high commercial traffic areas or in low visability situations (even after dark) it will give you invaluable information, and is a great safety device.
 
Hi Alexander, and welcome aboard!

Although cloud-based AIS is a fun hack, it really isn't yet developed to the point that I would care to count on it as primary navigational or safety equipment.

Last summer, on our trip up the coast, I played with land-based AIS monitoring networks a bit, comparing it to the results obtained by the class B transceiver on-board. Although I was expecting to find gaps in coverage in the rural sections of the coast, I was surprised how many gaps existed even in fairly urban and populated areas. As we have been from San Francisco to Two Harbors several times, always have our AIS on, and are usually within radio range of the shore, a quick historic search for WDF(remove this spam reducer)4868 will show which coastal areas are covered, and how much is not.

Satellite based AIS is starting to come along, but cannot transmit at this time. A major issue that has to be overcome is that the AIS transmitting protocol, which was developed in order to prevent ships that are within range of each other from transmitting at the same time, was not designed to have the number of ships as that are within range a satellite. The ship based units that are out of sight of each other can, and do, transmit at the same time as each other, thus creating a digital mess.

Given how slowly marine users and leadership have adopted new technology (even a VHS radio is considered voluntary on most recreational boats, and some still don't have them) I suspect that a comprehensive, transceiving, cloud-based AIS is still many years off.

David
 
As I stated in an earlier post, I don't use (or need ) this app for navigation. It's main use to me is to show my position to my son with whom I always share my cruising plans (and vice versa), . It provides a position and track so he always knows where we are in case of trouble. For my phone to transmit my location it does need a cell connection but does not need wifi. When we leave cell coverage the position shows last contact position and refreshes to new position as we re-enter coverage. It triangulates using towers so when offshore and in contact with a single tower it will show the tower position. A last known position is much better than "whereabouts unknown" if help is needed.
With a 5 min refresh rate, if you have coverage, this app shows ships of interest way before they become a threat and it shows course and speed.

Given the fact that most boats on the water don't have AIS I don't consider AIS as a reliable defensive safety net when compared to radar and an attentive helmsman. It is a useful tool and it will likely get to be more useful but only a tool.
A good discussion thanks
 
Alexander":chyvl831 said:
Given the fact that most boats on the water don't have AIS I don't consider AIS as a reliable defensive safety net when compared to radar and an attentive helmsman. It is a useful tool and it will likely get to be more useful but only a tool.
A good discussion thanks
Click to expand...

Ais is a very good safety tool, and can be better than radar in many instances.(Blind spots in traffic patterns, ICW) Basically all larger (some small to medium also) commercial vessels have AIS A. An increasing number of small recreational vessels have AIS B.

You mentioned a 5 minute lag. A ship going 20 knots will cover 8, 800 feet and can significantly change course in that period of time. If your C Dory is also going 20 knots your closing speed can be as much as 17, 600 feet in the 5 minute time.

You mention triangulation by cell towers? Does your phone not have a GPS chip in it? All modes cell phones have a GPS chip. It would seem that you are also using data time by sending your position to the phone.(at a cost) If you see your phone as a safety feature, then you would be far better served by a PLB or EPIRB. An alternative for your family is SPOT one DeLorme tracing devices which are not dependent on cell towers.

Don't forget Rule 7a.) : Every Vessel Shall use all available means appropriate to the prevailing circumstances and conditions to determine if risk of collision exists.

A prudent mariner uses all tools at this hands. I have been using an AIS receiver for several years, and if I was regularly boating in crowed waters or areas of high commercial use, I would have at Least Class B AIS aboard.
 
Hi Bob , I agree with your points. My discussion was relevant to the free apps not real AIS. I do not use the Apps for my nav tool while underway. My area (Stuart,Fl.) includes 98% private vessels and very little fog problem and mostly daytime ICW travel. I have not used real AIS so I defer completely to your experience with it as to it's usefulness.
Real AIS does show up on the app and it has world wide coverage and specs and pics of vessels as well as course and speed. By zooming out you can watch vessels as many miles away as you want and track their course and speed long before they are near your position. It does have some value. I just don't need it for my normal travel, I do transmit the signal for my son but I don't run a laptop while underway.
My son keeps tabs on us using his Samsung Galaxy 4 on his 4g phone network in Boston. It is only on internet but wifi is not needed needed.
My error on the gps issue. We don't loose location anymore but we used to. Important to know that the position generated with this app IS NOT seen by real AIS systems on other vessels.
 
I'm new to this thread, and guess completely clueless about AIS. But from the quick review I made of this thread, it sounds like it could be useful tool on the Mississippi, perhaps on the Great Lakes, and also in the San Juans if I make that trip next summer. Sooooo, any recommendations for inexpensive stand alone units? Or recievers/transponders that would be able to connect up with an old Pathfinder radar or newer Garmin GPS? Colby
 
Many of the newer radios from both Standard Horizon or Icom have the AIS built in. It just takes a couple of wires connection to the chart plotter and you have the AIS overlaid on the charts. The older SH Matrix 2100 is about $200, and the slightly easier to use 2150 is a little over $300.

There are cheaper ways: Digital Yacht AIS 100 is about $165. Miltech has a number of receivers for in the $200 range.

I happen to have the older Standard Horizon Matrix 2100--a couple of wires to the Garmin chart plotter, and hit a few menu buttons, and you are ready to do. This has the radio receiver, plus using the radio's antenna.
 
Thanks. What about transmitter. Do any of those radios transmit AIS also? The 2150 sounds like a nice unit, but since I have both an older Ray Marine Pathfinder Radar, and a newer Garmin GPSMAP, I would think it would be easy enuf to connect the older 2100 to one or both of those. (I am concerned if the radar would communicate with the 2100. As of now, it will not connect with the new Garmin. Either of these have a larger screen than the VHF 2150 would have. Also, I see a "class D" or a "standard" model of the 2150. Is there a difference or is it just advertising? Colby
 
thataway":vxipttvo said:
Many of the newer radios from both Standard Horizon or Icom have the AIS built in. It just takes a couple of wires connection to the chart plotter and you have the AIS overlaid on the charts. The older SH Matrix 2100 is about $200, and the slightly easier to use 2150 is a little over $300.

There are cheaper ways: Digital Yacht AIS 100 is about $165. Miltech has a number of receivers for in the $200 range.
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Note: the AIS in the Standard Horizon (2100, 2150, 2200) all are AIS receivers only, not full, (or active) AIS.

As to using the AIS for safety. I find using the AIS is much quicker than radar for determining CPA (Closest Point of Approach) and the TCPA (Time to CPA). It is a one button click, instead of doing MARPA on the radar.

Harvey
SleepyC:moon
 
As for transmitting--there is Class A--which is what commercial vessels use. These will begin at about $2,500. The Class B, which has a lower power transmitter, and less frequent transmissions starts for a very basic unit at about $500. The one I recommend is what Harvey is considering--the Vesper Watchmate 850--about $800 or a bit more. This has a 5" screen for viewing positions of the various vessels, or the information about a single vessel or several vessels. It also has a built in GPS chip and antenna, so the only hook up is to an antenna and power. You can also have the AIS on your chart plotter. My preference is for a separate specific AIS antenna, But you can consider a good quality splitter.

As for Radios--I like to have two VHF radios, so I can monitor two different frequencies--there are some advantages to that over a dual watch or scanner. So I have a radio which has the built in AIS receiver. My AIS is overlaid on a 5" Garmin (540) receiver. I have a 740S which I could overlay the AIS on if necessary. The chart plotter has to have a high speed input port--38400 baud.

I certainly agree with Harvey about the rapidity of the CPA determination. It is virtually automatic and is easily updated. I come from the school of taking bearings or using Radar plotters to determine CPA. MARPA requires a gyro-rated heading indicator in most cases. Although radar overlay can be done on chart plotters without an accurate heading indicator it does not work at zero speed, and it is not as accurate as when utilized with a very accurate heading indicator.

I think there are too many issues to allow most of the AIS receiving radios to give an accurate picture on the Raymarine Pathfinder Radar (I believe it does not have the 38,400 baud NMEA input port) The Garmin will work fine as long as it has the 38,400 Baud input. Class "D" means that it is a dual channel receiver--with a dedicated receiver on channel 70 for DSC calls.

AIS has two channels: AIS 1 161.975 MHz, and AIS 2 162.025 MHZ. These are at the upper end of the Marine VHF spectrum, and that is why I recommend an antenna tuned specifically for AIS. Your VHF channel 16 is at 156.800 MHz. You want to have your VHF antenna turned for the min SWR at 156.000 MHz to 157.500 MHz. As you can see the AIS is some distance above this, and will often have a high SWR (lower effective radiated power) with an antenna tuned for 156.800 MHz (This will only be really important with a transmitting AIS unit.)
 
I just installed a Vesper Marine XB-8000. It is basically a "black box" (actually blue) version of the WatchMate Vision.

The Vision and XB-8000 come with WiFi Multiplexer's, which means the stream all the NMEA data to computers, smartphones, tablets etc. It's pretty slick.
 
Thinking pretty sure I'm going to go ahead and order the GX2150 from Amazon. From what I'm understanding here and reading about it, it's basically a VHF radio that also has DSC and can recieve AIS signals. It can then show those AIS positions on it's own screen, or I can connect it in with my GPSMap 541 so that it shows on my "map". Others ships/boats will not receive any kind of AIS signal from me, but in a mayday, I still have the DSC. But in a busy commercial shipping location, I should be able to "paint" all the commercial traffic. Does this about sum it up? I too prefer two VHF radios, which I now run. One of them is an older one, that I like because of it's scan set up. The other one that came with the boat, has DSC, but it's always been very confusing to use/setup, and is very likely the one I will replace. Oh yeah, also looking at getting the Standard STD-240SW PA Horn Speaker to go with the radio. Anyone know if this will be a good combination. Especially to use the Foghorn capibility of both? Colby
 
Here's a place that'll save you $17 over Amazon" the GPS Store. Both have free shipping.

Not only does that radio have AIS and GPS, but it also generated fog signals. I've needed that once or twice.

Just a suggestion. I've had good luck both places.

Boris
 
Colby, you have it right. But the area of the screen on the radio is so small, that I don't consider it very useful. It is very easy to attach to the Garmin Chart plotter that you have---assuming it has the 38,400 Baud NMEA port.

The Watchmate vision does add the WiFi and a rough base map. The XB 8000 has the Wifi, and GPS about $50 to $100 less than the Watchmate 850--and you can use the screen of your tablet.
 
Thanks all for the comments. Boris I just ordered it from The GPS store. There is also a manufacturers $50 rebate, so I think the pricing on it is pretty good. Hoping that I get the latest version however and not something that has been sitting in the warehouse as one of Standard's initial builds.... Still looking at what speaker to get. I kind of like the Standard Horizon 240SW 5" x 7" 40 Watt 4 OHM Hailer Horn, from what I read. Colby
 
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