AIS from VHF

[yonubear]

ok thanks that makes sense now I want an honest opinion here if it was you would you go throught the hassle of connecting the VHF to the PC or simply leave it seperate

[xymotic]

Well, I'd prioritize having the GPS tied to the VHF and properly functioning DSC would be #1.

Yes, personally I would mess around with it until I got it working, but then again I'd spend too much money, time and eventually I'd go NMEA 2000 and AIS and all that, because I'm a dork.

It really depends on how badly you want it all integrated @ the PC and how difficult it is to run the wires. I like that sort of thing, so for me it would be no big deal. Other people HATE electrical/computer stuff and for them it's of much lower importance.

[yonubear]

well lol I don't mind running wires or that just hate doing something it there is no real benefit oh and connecting a gps to the radio is on the list anyway I am just waiting for it to arrive. oh as to elec/comp stuff I have no problems for that as my day job is PC/network tech and no not for best buy lol

[xymotic]

Well yeah, then definitely you should do it, all the tech stuff scares people off, but it all works EXTREMELY well, once you finally get it working

[yonubear]

thanks my biggest issue was getting it wired then finding out that open CPN would not know what to do with the data from the radio.

heck I wouldn't even mind it not working after I wired it if it wasn't for the hiding of the wires

Thanks,
Reg

[svBeBe]

Originally Posted by yonubear

ok now that I think everything has settled down I just have a simple question if I run the nmea wires down to the nav PC and use the radio GPS will OpenCPN have any idea what to do with the DSC call data when it comes in or should I not even bother running the nmea connection to the PC?

Yonbear,

In CF you will get all sorts of "expert" replies, but rarely a direct answer to your question. I think you may be under the wrong impression as to what you get from the NMEA Out on your new VHF. I am not familiar with your radio, but I am familiar with 5 or 6 new models. All those VHF radios that I am familiar with will repeat (on the NMEA Out) only the NMEA data sent to the VHF via NMEA Input on the VHF.

So the direct answer to your question is that you are only going to receive NMEA sentences from the VHF NMEA Out that are sent to the VHF (normally from the GPS).

The NMEA Out terminal is good for folks that need to share the NMEA data from a GPS with other NMEA listeners as it allows a "daisy-chain" or multiplex effect.

There is a possibility of a "ground loop" which will send NMEA gibberish from the NMEA Out on the VHF...won't go into detail as to why, but this is not uncommon when "connected" NMEA equipment gets its power from different sources. If this happens to you, disconnect the NMEA ground from the NMEA Out on the radio leaving only the (+) NMEA connected to the next piece of equipment. This should solve the "ground loop" effect.

Hope this helps you.

BTW, I am waiting for a VHF manufacturer to produce a VHF/AIS transponder combo that also has a screen on the mike that allows selection of a AIS target and VHF connection via DSC. I believe all of the technology is there and I am ready to move from an AIS receiver up to an AIS transponder.

Bill

[yonubear]

that makes great sense

I am just going by the book for the VHF it actually says that if connected to a chartplotter via nmea out when a DSC is recieved it will display on plotter other than that I have no idea if/how it works as my main/only plotter is the PC

[xymotic]

Originally Posted by svBeBe

Yonbear,

In CF you will get all sorts of "expert" replies, but rarely a direct answer to your question. I think you may be under the wrong impression as to what you get from the NMEA Out on your new VHF. I am not familiar with your radio, but I am familiar with 5 or 6 new models. All those VHF radios that I am familiar with will repeat (on the NMEA Out) only the NMEA data sent to the VHF via NMEA Input on the VHF.

So the direct answer to your question is that you are only going to receive NMEA sentences from the VHF NMEA Out that are sent to the VHF (normally from the GPS).

The NMEA Out terminal is good for folks that need to share the NMEA data from a GPS with other NMEA listeners as it allows a "daisy-chain" or multiplex effect.

There is a possibility of a "ground loop" which will send NMEA gibberish from the NMEA Out on the VHF...won't go into detail as to why, but this is not uncommon when "connected" NMEA equipment gets its power from different sources. If this happens to you, disconnect the NMEA ground from the NMEA Out on the radio leaving only the (+) NMEA connected to the next piece of equipment. This should solve the "ground loop" effect.

Hope this helps you.

BTW, I am waiting for a VHF manufacturer to produce a VHF/AIS transponder combo that also has a screen on the mike that allows selection of a AIS target and VHF connection via DSC. I believe all of the technology is there and I am ready to move from an AIS receiver up to an AIS transponder.

Bill

NONE of the radios (or any other component I've used EXCEPT a plotter) will repeat an input to the output. Including the new, high end S&H 2150.

The one exception I know of is the Em-trak AIS class B which specifically touts it as a feature.

[bewitched]

Lots of options for routing the NMEA. One would be to take the NMEA data from the gps and feed it to both the pc and the radio independantly and also a NMEA route from the radio to the pc.

Google for virtual serial port emulator (vspe) which is a great little software that allows you to have multiple inputs on the same com port by creating virtual ports. Can also handle different baud rates so that you can have gps, instrument, AIS etc all coming into the same port.

[bewitched]

You should get radio generated info on the nmea out.

In other words dsc positions of other vessels that you have received position reports from. A handy feature if you have no AIS.

[xymotic]

Originally Posted by yonubear

that makes great sense

I am just going by the book for the VHF it actually says that if connected to a chartplotter via nmea out when a DSC is recieved it will display on plotter other than that I have no idea if/how it works as my main/only plotter is the PC

The way this works is very linear and very simple.

The GPS goes to the radio simply and only so that if YOU hit a dsc function the radio will transmit YOUR position.

When you connect the radio to a chartplotter or PC it tells the plotter that there is a DSC call at coordinates x:y It does NOT tell the plotter everything else that it may have heard on the NEMA network: your position, wind speed, water temperature etc.

It is then up to the plotter to calculate a course from its position to the new one.

now for you to do this, basically you need the GPS to "talk" to the PC and the VHF and for the VHF to talk to the PC but daisy-chaining devices definitely is fraught with peril.

[yonubear]

the pc connections is the simple parts I can get that working I was simply worried about the software interpreting the dsc X:y

Thanks

[Viking Sailor]

Originally Posted by yonubear

the pc connections is the simple parts I can get that working I was simply worried about the software interpreting the dsc X:y

Thanks

Found the following info on DSC messaging in the OpenCPN online help:

DSC and Buddy via AIS. | Official OpenCPN Homepage

You might be able to connect the output of the GPS receiver directly to the inputs of both the VHF radio and the PC. Most NEMA devices can drive the inputs of up to three other devices.

Best of luck,

[DotDun]

Originally Posted by yonubear

the pc connections is the simple parts I can get that working I was simply worried about the software interpreting the dsc X:y

Thanks

Even if OCPN interprets DSC properly, what are you expecting? Other than 'all ships' call or distress calls, you won't see any traffic. Your radio will ignore traffic not destined to your MMSI number. You can't monitor MMSI-to-MMSI DSC traffic. If you want to find the position of someone, you need to know their MMSI number, program it into the radio (usually via a crappy UI), then send the request. Depending on how the other radio is programmed, it may ignore your request, sound an alert, or automatically respond. In my area, there probably isn't more than 3 or 4 distress calls a year, and most of those are someone messing with their radio and doesn't realize what they are doing.

Don't get your hopes up for immediate gratification for doing the work of running the wire. Connect a GPS to the radio? Yes! Get your own MMSI number and program your radio? Yes! Learn how to use DSC properly? Yes! Connect it to OCPN? If it's easy, yes!

[svBeBe]

Originally Posted by xymotic

NONE of the radios (or any other component I've used EXCEPT a plotter) will repeat an input to the output. Including the new, high end S&H 2150.

The one exception I know of is the Em-trak AIS class B which specifically touts it as a feature.

You would be interested in knowing that all of the Thrane and Thrane models do repeat NMEA that is Input into the VHF to the NMEA out.

Bill