Is AIS in the house?

Just for clarification, the Standard horizon GX 2150 does not have a built in GPS, that I know of. It does have the Fog/hailer and AIS receive and it is a nice radio.

I have been using the Standard Horizon 240SW 5" x 7" 40 Watt 4 OHM Hailer Horn, set up between two VHF's, both with the hailer/fog capability and switched to the horn. I works well, good volume and clarity.

Should you decide to add an active AIS, the 2150 can be set to ignore it;s own MMSI position, thus escaping from the "Dangerous Target" warnings.

Harvey
SleepyC:moon

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BRINGING THIS ONE BACK FOR SOME UPDATES

Recently I have been watching a YouTube series by a Merchant Marine Professional tug captain. ( TimBatSea ) He has recently decided to become a recreational mariner as well, and purchased a 40 ft sailboat. I started watching him while he was working in the Harbors of New York, and now he is working down in the Caribbean.

His most recent You Tube is talking about the limitations of radar and the advantages of AIS. Some of what he is saying does apply to us as recreational boaters where we mix with commercial traffic, and some who get farther from shore in less than flat water conditions. It is worth hearing his reasoning. Here is the link for "What You Don't Know About RADAR" :

https://www.youtube.com/watch?v=Xqa9gaIs8aU

One thing he does not get into is how AIS can see over islands or around bends in the river.

Harvey
SleepyC :moon

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One thing he does not get into is how AIS can see over islands or around bends in the river.
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But only if the other boats one has it. Still just an add on to having radar. I still see people commenting < not here< that they got radar and AIs so other boats can see them. That is not how radar works. and unless you have transmit, which most dont, thats not how AIS works either.

Had to break it to a women on the dock that no one can see your radar but her. She thought it made others see her on radar better. Lots of misconceptions out there.
 
One thing he does not get into is how AIS can see over islands or around bends in the river.
Click to expand...

The reality is that AIS is line of sight, and a limited horizon similar to what VHF radio has. (This neglects tropospheric Ducting, which is a condition where VHF, UHF and even microwave radio signals bounce in the atmosphere, and can be picked up hundreds of miles away) The signal is digital, and it can bounce off cliffs, buildings etc to some degree and be "heard" where it is not exactly line of sight. It also depends on the height of antennas. But generally the AIS signal does not violate laws of physics.
 
Agree, AIS cannot break the laws of Physics, but in reality, working around in the islands, both San Juans and the east side of Vancouver Island, I frequently can see the ferries, tugs, water taxis and large commercial ships, when they are on the other sides of islands from me. Yes, their antennas are way higher than mine, and yes they are transmitting their AIS at 5 watts, so maybe they scatter or bend a bit more than than my 2 watt.

In any crossing or low viz situation, I will contact the other vessel and confirm 2 things, #1, that they can see me, either via radar or eyeball, and #2, That they can see me on their AIS.

Harvey
SleepyC :moon

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before buying AIS try using the " marine tracker App" on your phone while on the water. I run it all the time. It can be an hour or a second behind but its a good test bed for if you really need ais to began with, I dont but if I was going to get a new vhf for some reason I would get one with AIS . its just a little money and you cant take it with you. You can on the other hand have a Viking boat funeral and that's better.
 
starcrafttom":2pcinsom said:
before buying AIS try using the " marine tracker App" on your phone while on the water. I run it all the time. It can be an hour or a second behind but its a good test bed for if you really need ais to began with, I dont but if I was going to get a new vhf for some reason I would get one with AIS . its just a little money and you cant take it with you. You can on the other hand have a Viking boat funeral and that's better.
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I've seen some of those web based marine traffic sites with poor performance. Not only do you need a live internet connection for them to work, the position reports can be DAYS out of date. I was in SoFL once and was watching a ship go by while looking at marinetraffic.com. The ship in front of me was last reported on that website somewhere else and the report was 3 days old.

While interesting to look at, I certainly would not rely on any website for real-time AIS positions for collision avoidance.
 
Will the situation where you're watching the boat go by but the reporting is 3 days old is more likely due to the fact that they didn't turn it on. you have to have AIS in the boat and you have to turn it on. Like I said it was just a way to see if you like the system I've seen boats that are right in front of me and show up and I've seen boats whos signal is 2 hours old old. But it is a way to see if you like the technology or not before you slap down a lot of money. I use it to see where people have been more then where they are now.
 
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