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Discussion Starter · #1 ·
Now that I have an AIS system (Raymarine AIS650) why don't a show up on Marine Traffic? When I look at the target data using proAIS2 it shows a base station about 1 mile from me. Can someone explain how it is supposed to work?
 

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Discussion Starter · #3 ·
Good line of sight to the Marine Traffic receiver site near you? Are you sure it's a Marine Traffic site? Have you tried aprs.fi? They use different receivers. Do you know for sure you are transmitting?

Where in MD are you?
Marine Traffic did pick me up once while going under the Chesapeake Bay Bridge, so I think I'm transmitting. My slip is in Chesapeake Harbour near Annapolis. Perhaps the base station listed on the proAIS2 target list was not a Marine Traffic base station, but aren't there any others near Annapolis? At what sort of range should I be visible with my Raymarine AIS650? I would think I would be showing up much more often.
 

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Sailboat Reboot
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At what sort of range should I be visible with my Raymarine AIS650? I would think I would be showing up much more often.
AIS uses two dedicated VHF marine radio bands. Thus, your range will be approximately the same as your range transmitting and receiving on your VHF. There are technical reasons why the range might be a bit longer but generally the working distances are close enough for government work.

Fair winds and following seas :)
 

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Marinetraffic.com has receivers only. They will never come up as base stations.

Base stations you see are government, coast guard, harbour authorities etc.

To know if Marinetraffic.com works in your area you need to see vessels on it that are very close to you.

:)

ProAIS2 will show you that you are transmitting, but to check how far you need another boat to check for you when they are moving away from you. The difficulty is the digital package should go further than voice, so you cant hear them tell you on VHF that they can no longer see you.
 

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Mermaid Hunter
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Marine Traffic did pick me up once while going under the Chesapeake Bay Bridge, so I think I'm transmitting. My slip is in Chesapeake Harbour near Annapolis. Perhaps the base station listed on the proAIS2 target list was not a Marine Traffic base station, but aren't there any others near Annapolis? At what sort of range should I be visible with my Raymarine AIS650? I would think I would be showing up much more often.
Hmm. MarineTraffic is showing lots of boats on Back Creek and in Selby Bay. Chesapeake Harbour should show up.

I went back a week on aprs.fi but didn't see you there either.

AIS is on VHF channels 87B and 88B. Have you tried listening for your own transmission?

If those simple things don't work you'll have to start looking at your installation. I live in Eastport off Harness Creek. Let me know if I can help.
 

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Discussion Starter · #7 ·
Hmm. MarineTraffic is showing lots of boats on Back Creek and in Selby Bay. Chesapeake Harbour should show up.

I went back a week on aprs.fi but didn't see you there either.

AIS is on VHF channels 87B and 88B. Have you tried listening for your own transmission?

If those simple things don't work you'll have to start looking at your installation. I live in Eastport off Harness Creek. Let me know if I can help.
Thanks. My system was professionally installed; I hope it's not an installation problem. There is a boat called Bernadette that has her AIS on 24/7 in Chesapeake Harbour. I don't see her on either website. Perhaps it is just a dead spot. I plan to go for a sail on Sunday. I guess I'll just have to try calling a few AIS targets and ask if they can see me.

How would I go about listening to my transmission? How would I be able to tell it's my data?
 

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Mermaid Hunter
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My system was professionally installed; I hope it's not an installation problem.
*bites tongue* *hard*

There is a boat called Bernadette that has her AIS on 24/7 in Chesapeake Harbour. I don't see her on either website. Perhaps it is just a dead spot.
Possible. I'm surprised those town houses block anything. They are pretty lightly constructed.

I plan to go for a sail on Sunday. I guess I'll just have to try calling a few AIS targets and ask if they can see me.
You can also look at MarineTraffic.com (10-15 minute delay) or aprs.fi (2 or 3 minute delay) on a smartphone.

How would I go about listening to my transmission? How would I be able to tell it's my data?
You can't tell for sure. If you hear sqaucking on 87B or 88B try pulling the antenna connector off your radio (don't transmit) and see if you still hear it, although you may still hear Bernadette.

Note that aprs.fi lets you look at data up to a week old, so even if you don't talk to anyone you can get a pretty good idea of whether you are transmitting or not.

You aren't in silent mode are you? Within 5 minutes of power-on the indicator should be green. If it is blue you are in silent mode.

dave
Raymarine Certified Technician
 

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Discussion Starter · #9 ·
*bites tongue* *hard*
Well everything else is working and their wiring is neat and orderly. Prettier than I could / would have done. Hopefully the quality is there too.

Possible. I'm surprised those town houses block anything. They are pretty lightly constructed.
Agreed. That's why I'm surprised I'm not being pick up on the websites. But then again Bernadette isn't either.

You can also look at MarineTraffic.com (10-15 minute delay) or aprs.fi (2 or 3 minute delay) on a smartphone.
I've been using the MarineTraffic app on my phone to see if I'm showing up. I didn't know about the delay.

You can't tell for sure. If you hear sqaucking on 87B or 88B try pulling the antenna connector off your radio (don't transmit) and see if you still hear it, although you may still hear Bernadette.

Note that aprs.fi lets you look at data up to a week old, so even if you don't talk to anyone you can get a pretty good idea of whether you are transmitting or not.

You aren't in silent mode are you? Within 5 minutes of power-on the indicator should be green. If it is blue you are in silent mode.
According to PsroAIS2 I'm not in silent mode.

I came across this AIS 650 Has Very Short Transmit Range - Raymarine Technical Forum

I have the AIS100 splitter. My antenna is on top of the mast. I'll check the VSWR with the ProAIS2 app this weekend.
 

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Mermaid Hunter
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Well everything else is working and their wiring is neat and orderly. Prettier than I could / would have done. Hopefully the quality is there too.
I apologize if I came across as snarky. I worked on three boats last week that needed significant re-wiring to get installed systems to work reliably. On one boat I pulled out 400 feet of wire abandoned in place.

The AIS 650 runs at the Class B specified power output. The moderator response has a typo - there is no such thing as a VSWR of 0.8:1. 1.0:1 is perfect. The AIS 650 will shut down to protect itself with a VSWR somewhat above 2.0:1. Note that the original poster found an installation problem that resolved the issue.

I have the AIS100 splitter. My antenna is on top of the mast. I'll check the VSWR with the ProAIS2 app this weekend.
I'm not a fan of splitters. I encourage my customers to avoid them. You will have a 3 dB reduction (1/2 power) through the splitter and a small additional reduction due to the additional number of connectors - bigger yet if cheap crimp connectors are used. The signal reduction applies to your VHF as well as to the AIS.

If you like we can schedule a time to meet up and I'll put an antenna analyzer on your system for you.

You can certainly get systems with splitters to work (I have). My basic recommendation is to leave the masthead antenna to the fixed VHF and put another antenna on the pushpit rail, on a spreader, or an arch. My AIS antenna is on a radar pole. I only use solder-solder silver-teflon connectors and the best coax I can get.
 

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Discussion Starter · #11 ·
If you like we can schedule a time to meet up and I'll put an antenna analyzer on your system for you.
Thank you. I may take you up on that at some point.

FWIW...

I was being picked up sporadically on MarineTraffic and aprs.fi this weekend. Both sites listed K3ARS as the source. K3ARS is in Chestertown, MD which is 24 NM from my slip. As far as I can tell this is the closest base station to Annapolis. It's no wonder that I don't show up consistently. At that range I'm surprised I show up at all.

I did ask a few boats if they could see me on their AIS. All said they could, so I guess it's working as it should. One said my data was not populated in the system, but I think that was due to my single antenna / splitter setup. They called me back a few minutes later and said all the data was there now.

My VSWR was showing up in ProAIS2 as 1.1:1.

I may add a second antenna some day, but what I have is going to have to be good enough for a little while.
 

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Mermaid Hunter
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I did ask a few boats if they could see me on their AIS. All said they could, so I guess it's working as it should. One said my data was not populated in the system, but I think that was due to my single antenna / splitter setup. They called me back a few minutes later and said all the data was there now.
That should not have anything to do with the splitter unless you were spending a lot of time talking on your VHF after you powered up. Static data (IIRC) for Class B is only sent every six minutes, and if you're talking on the VHF the splitter will block the AIS transmission.
 

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Maine Dub
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I tried installing a class B ( Si Tex) and am having problems with the vhf ant also. It starts up fine, has good GPS signal, sends first location with mmsi # and then goes to fail mode(ais ant). I have a new dedicated ant on the pushpit and even hooked up a spare with a new cable. This is the second black box I have tried and both vhf ants work fine with voice comm. where to now? :eek:
 

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Maine Dub
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Talked to an engineer at Si-tex. Seems like you need an SWR on your antenna that is less than 5 to 1. Interference from metal near the antenna ( like on the pushpit)is a no no also. I hooked up to the mast head antenna and all is well. With a laptop plugged into the USB on the AIS you will get a readout on the current SWR after you get the fail light or after a few minutes if all is well. Seems like your vhf radio will T and R on a pretty lousy antenna.:)
 

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Mermaid Hunter
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Talked to an engineer at Si-tex. Seems like you need an SWR on your antenna that is less than 5 to 1. Interference from metal near the antenna ( like on the pushpit)is a no no also. I hooked up to the mast head antenna and all is well. With a laptop plugged into the USB on the AIS you will get a readout on the current SWR after you get the fail light or after a few minutes if all is well. Seems like your vhf radio will T and R on a pretty lousy antenna.:)
There is no excuse for an VSWR as high as 5:1.

I'm not sure what "interference from metal near the antenna" means. There can be shielding and directive effects, but not interference. The near-field effects of metal near the antenna at the mast head and on the pushpit is not significant, absent "junk on the back."

Just because the equipment functions doesn't mean it is performing as you expect.
 

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Maine Dub
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Thanks Dave. Do you suppose the software in the AIS is just coming up with wildly high SWR. I am not very electronic smart but I have never had so much trouble with plug and play.:)
 

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Mermaid Hunter
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Do you suppose the software in the AIS is just coming up with wildly high SWR.
Very unlikely. If it was a software problem there would be more widespread reports of similar issues.

It shouldn't be hard to get VSWR well below 2:1. Any local ham (check ARRL.org for clubs in your area) with a VHF SWR meter can help you. An antenna analyzer is better ...
 
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