Lowrance Plotter to Radio Ocean VHF

[superheat6k]

I have just bouight a Radio Ocean RO-4800 VHF set with built in AIS engine, and I am connecting this to my Lowrance HDS-7M plotter.

The idea is that the VHF sends the AIS data to the Plotter and the Plotter sends its Lat Long data to the VHF for DSC transmission.

However, it would seem I can either have the units talk to each other either at one Baud rate when the Plotter picks up the AIS at 38,400 Baud or the VHF picks up the GPS Lat / Long when at 4,800 Baud.

The settings on both units do not make it clear whether the selected baud rate is for sending or receiving, and I cannot find individual settings for both.

So I cannot get both functions to work at the same time.

As I can get the comms to work individually I am sure I have got the hardwire connection correct, so it seems to be the settings.

Any one able to help on this ?

Unfortunately the idiots guides provided with the units are about as clear as mud on this topic.

 

[maby]

The manual for your radio claims that the AIS output can be set to 38,400bd or 4800 bd, but it does not make any mention of being able to select the speed for the GPS input, so I guess you need to set your plotter to 4800 and the AIS output to the same. I think you may find that 4800 is a bit slow for AIS in congested waters - you may lose some messages.

http://www.furuno.se/uploads/tx_vtfuruno/RO-4800_P-4800.pdf

 

[PaulGooch]

A quick look at the Lowrance manual tell us that you can configure the speed for comm port one and comm port two. Unfortunately, whichever speed you set comm port one to applies to input and output data. Same with comm port two.

So if you use either comm port for AIS and VHF, they cannot work, unless you can slow the AIS output on the VHF down to 4800 as Maby describes. It's not an ideal solution, for the reasons he gives.

A better solution is to use port one output for GPS data to the VHF set, set at 4800 and use port two input for AIS data, set at 38400.

 

[oceanfroggie]

No problem. Separate wires used. VHF will TX the AIS data to the plotter on one port at 38.4kb whereas the VHF will RX lat/long data received from the plotter at 4800b. Separate comm ports.

 

[PaulGooch]

No problem. Separate wires used. VHF will TX the AIS data to the plotter on one port at 38.4kb whereas the VHF will RX lat/long data received from the plotter at 4800b. Separate comm ports.

Only if he changes how he currently has it wired. A lot of plotters will allow baud rates to be individually set for each and every input and output port. Any particular port can RX at one baud rate and TX at another. The Lowrance cannot do this, if port one is set to 4800 it will TX and RX at that speed. So he needs to TX on one port and RX on the other.

 

[maby]

Only if he changes how he currently has it wired. A lot of plotters will allow baud rates to be individually set for each and every input and output port. Any particular port can RX at one baud rate and TX at another. The Lowrance cannot do this, if port one is set to 4800 it will TX and RX at that speed. So he needs to TX on one port and RX on the other.

I'm not convinced by this, Paul - never seen any plotter that allows different speeds for input and output on a single port. Inside the plotter, they will be using a UART chip for the I/O and they are virtually all only capable of clocking the input and output at the same speed.

 

[superheat6k]

Thanks for all the advice. Looks like I will be returning both units to Force Four to sort this problem out !

Having spent over £1,000 on this lot from them I think it is reasonable to expect the set up to work as prescribed.

I have already had trouble with the first HDS-5M unit supplied when the screen went black in patches after 2 months use, and had to force the issue to get this sorted, however I stuck with the Lowrance and upgraded to the HDS-7M.

Not so sure I will be sticking with this now as key to buying both units was the ability to host AIS on the Plotter and obtain AIS from the VHF set.

Why oh why can't these manufacturers work to the same standards of data comms !!!

 

[PaulGooch]

Thanks for all the advice. Looks like I will be returning both units to Force Four to sort this problem out !

Having spent over £1,000 on this lot from them I think it is reasonable to expect the set up to work as prescribed.

I have already had trouble with the first HDS-5M unit supplied when the screen went black in patches after 2 months use, and had to force the issue to get this sorted, however I stuck with the Lowrance and upgraded to the HDS-7M.

Not so sure I will be sticking with this now as key to buying both units was the ability to host AIS on the Plotter and obtain AIS from the VHF set.

Why oh why can't these manufacturers work to the same standards of data comms !!!

It will work if you change two wires.

 

[superheat6k]

Thanks Paul, however, the HDS-7M can only TX / RX via Comm 1 as RS-422. Comms 1 & 2 is only available to the HDS-8 or 10 via RS232.

I have hooked up the TX + & - to the RX + & - from the HDS to the VHF, and vice versa for the AIS comms TX from the VHF to the HDS RX.

I was worried I had got the cross over wrong, but the fact I can get the two to talk, albeit at differing rates confirms I have got this right.

Personally I would have expected the Radio Ocean to accept incoming data for the DSC function at 38,400 Baud, after all it is able to transmit AIS data at that rate.

I have now referred this to the retailers where I bought both units (fortunately both from the same place).

I wil let you now what the resolve is, as the instructions provided are not very clear, especially as the Radio Ocean manual is not a good translation from French, and I have no chance with the French written section of the manual.

 

[PaulGooch]

I'm not convinced by this, Paul - never seen any plotter that allows different speeds for input and output on a single port. Inside the plotter, they will be using a UART chip for the I/O and they are virtually all only capable of clocking the input and output at the same speed.

My Garmin 4010 allows different speeds for all inputs or outputs.

 

[PaulGooch]

Thanks Paul, however, the HDS-7M can only TX / RX via Comm 1 as RS-422. Comms 1 & 2 is only available to the HDS-8 or 10 via RS232.

I have hooked up the TX + & - to the RX + & - from the HDS to the VHF, and vice versa for the AIS comms TX from the VHF to the HDS RX.

I was worried I had got the cross over wrong, but the fact I can get the two to talk, albeit at differing rates confirms I have got this right.

Personally I would have expected the Radio Ocean to accept incoming data for the DSC function at 38,400 Baud, after all it is able to transmit AIS data at that rate.

I have now referred this to the retailers where I bought both units (fortunately both from the same place).

I wil let you now what the resolve is, as the instructions provided are not very clear, especially as the Radio Ocean manual is not a good translation from French, and I have no chance with the French written section of the manual.

Apologies for that, i downloaded the installation manual from the Lowrance site and hadn't noticed it covered all models. You're right, it won't work as you would expect, which is really down to the lack of ports on the Lowrance.

 

[superheat6k]

If my suppliers can't offer a direct solution that allows both functions to work as expected then I will be looking at that option, although the opinion provided to me when I decided to stick with Lowrance after the initial problem with the HDS-5M, was that the Lowrance is the better unit.

But not if it won't talk properly !


I would appreciated opinions that I am right to expect both functions to work -AIS and DSC position and at the same time, after all that is why I paid my money !

As an aside I was somewhat surprised to see how large and bold the AIS triangular indicators are on the Lowrance, and these have no adjustments, although they do provide plenty of filters to clear the dross of class B transponders left on quite unnecessarilly by Solent sailors.

I personally feel the rules for use of Class B AIS should be tightened up as having a fog of AIS in crowded waters on a fine day is counter productive.

 

[maby]

If my suppliers can't offer a direct solution that allows both functions to work as expected then I will be looking at that option, although the opinion provided to me when I decided to stick with Lowrance after the initial problem with the HDS-5M, was that the Lowrance is the better unit.

But not if it won't talk properly !


I would appreciated opinions that I am right to expect both functions to work -AIS and DSC position and at the same time, after all that is why I paid my money !

...
.

I suppose that the retailer could deny responsibility for lack of compatibility between the products of two different manufacturers. NMEA0183 is getting a bit long in the tooth and a nightmare when you have more than two devices connected. OK - you only have two, but the radio includes the functionality of two devices in a single box.

I recently installed a Raymarine autopilot on our boat which was already equipped with Lowrance gear. I subsequently found that the autopilot would not follow a route plotted on the Lowrance and spoke to both manufacturers who told me that it is a known problem - Raymarine autopilots do not work with Lowrance/Simrad plotters. Fortunately, I had not been particularly interested in linking the two in that way, but I don't think I would have much of a leg to stand on if I had tried to complain to the retailer.

 

[superheat6k]

I will wait and see what the retailer says.

They clearly sold me a box saying it is AIS compatible for the plotter and another saying it would provide an AIS signal and display plotter data for its lat & long.

Whereas NMEA 0183 may be getting a bit old hat, it is still sold as a current and valid marine comms system and therefore fitness for purpose rules still apply.

If they won't do this then as far as I am concerned they will have a problem.

However, last time I had difficulties with the Lowrance they dealt with the issue very well in offering me a full refund, which I chose to spend on the more expensive larger Lowrance, followed uop by further expenditure on the VHF / AIS set.

 

[maby]

I guess the question will come down to what you asked the retailer and what they told you. The manuals for both my Raymarine autopilot and Lowrance plotter include sufficient caveats about compatibility to excuse either of any liability - they each say that they are compatible with other products of the same manufacturer and may be compatible with the products of other manufacturers. When i spoke to both Raymarine and Lowrance technical support, each explained that it was a known compatibility issue. I also mentioned it to the resident marine electronics engineer at our marina and he immediately replied "Oh, no - that will never work!"

 

[superheat6k]

Oh I am very clear on this. Having not long ago (2 weeks) resolved the earlier issue with my Lowrance and having supplied instead the HDS-7M unit, just last week I bought the Radio Ocean VHF from the same suppliers.

WILL THIS WORK WITH THE LOWRANCE HDS-7M FOR PROPER AIS & DSC FUNCTIONALITY - YES.

This followed my specific question as to the better fo the Lowrance and Garmin units to which I was clearly dfirected to the Lowrance.

We will see.

 

[maby]

Oh I am very clear on this. Having not long ago (2 weeks) resolved the earlier issue with my Lowrance and having supplied instead the HDS-7M unit, just last week I bought the Radio Ocean VHF from the same suppliers.

WILL THIS WORK WITH THE LOWRANCE HDS-7M FOR PROPER AIS & DSC FUNCTIONALITY - YES.

This followed my specific question as to the better fo the Lowrance and Garmin units to which I was clearly dfirected to the Lowrance.

We will see.

That seems pretty unambiguous. As discussed earlier, it does look like the radio can be set to transmit its AIS messages at 4800bd, so this should work, though it's not ideal - 4800 is a bit slow for AIS.

 

[PaulGooch]

This followed my specific question as to the better fo the Lowrance and Garmin units to which I was clearly dfirected to the Lowrance.

I'd say you were told wrong. IMO, Garmin are vastly superior to Lowrance. I've got a little Garmin 551 plotter here that would have no difficulty running your AIS at 38400 and DSC and 4800 and cost just £410 delivered. Same with my Garmin 620. My Garmin 4010 has 4 input ports and two output ports.

 

[superheat6k]

I have passed on to the supplier's that the problem may bot be resolvable. As said last time they were very good, so perhaps its the Garmin instead.

I will feed back further the end result, hopefully sooner rather than later.

 

[maby]

I like Garmin - only problem relative to the Lowrance/Simrad family is that Garmin do not have a broadband radar option - if you have no intention to install radar, I cannot see any downside in going Garmin.