Help re. chartplotter that will sync with DSC VHF

TWPC · 02 June 2019, 16:47

Good afternoon,

I and my wife are about to buy a used RIB. It has a functioning DSC-compatible Cobra VHF radio but the chartplotter, an ancient Eagle, is kaput.

We want to replace the Eagle with a new but not expensive DSC-compatible chartplotter. We do not need sophisticated navigation but do need the unit to have a decent depth gauge as we will be using the RIB in very tidal areas. We are not going to be looking for fish, just using the boat for family days out.

Can any of you advise me on a suitable chartplotter? Ideally we want a built-in unit to go into the cavity left by the Eagle (we can adapt!). I had thought all chartplotters would be DSC-compatible but this does not seem to be the case.

So far I have discovered that the Garmin Echomap Plus 65cv (£449 at Marine Store incl. transducer) is DSC-compatible but the Simrad Cruise 5 and Raymarine Dragonfly models are not.
Is that Garmin a good bet? Any other suggestions gratefully received.

Many thanks in advance for any help.

ShinyShoe · 02 June 2019, 17:48

DSC compat means different things to different folks.

What do you expect to happen?

Which Cobra?

TWPC · 02 June 2019, 21:24

Quote:

Originally Posted by ShinyShoe

DSC compat means different things to different folks.

What do you expect to happen?

Which Cobra?

Thanks for replying Shiny Shoe.

I want the VHF to be able to receive signals from the GPS so that, for example, when pressing the 'Distress' button it will transmit our location from the GPS.
i.e. Basic functionality!

I am not sure of the exact model of Cobra. It looks like an F45 or F55 but might be older. Picture attached.

ShinyShoe · 02 June 2019, 22:31

OK so you only want NMEA 0183 from GPS to Radio. That "should" be straightforward and a default spec for most.

You can get where a radio receiving a DSC alert will send it to the plotter to erm plot it. And the same with a DSC position poll.

You can also get plotters with AIS feeds that will let you click a target and call it from the map on DSC using its MMSI.

Hence the question.

ShinyShoe · 02 June 2019, 22:54

The Raymarine & simrad units have been designed not to talk to anything else. Presumably for cost and simplicity of support.

The Garmin is certainly capable of what your Cobra can do, and if the cobra was replaced in the future is capable of taking data from the radio too.

Simonh66 · 03 June 2019, 06:47

I have the Garmin on my RIB, great little unit

TWPC · 03 June 2019, 07:06

Thank you, much appreciated. NMEA 0183 does seem to be the key feature.

And thank you for the crash course in what AIS and DSC can do; very clever!

TWPC · 03 June 2019, 07:08

Oops. The message above is meant for ShinyShoe.

Thank you Simon for your view of the Garmin.

boristhebold · 03 June 2019, 07:09

First you need to identify what model of vhf radio you have so that you can look up it's specs and see if it communicates or can communicate with NMEA 0183 or NMEA 2000 or proprietory comms like 'seatalk' or equivalent.

Then once you have determined that and im guesiing it will be NMEA 0183, then you need to find a suitably priced chart plotter 'and sonar/depth sounder' that can communicate via NMEA 0183, if just a chart plotter then dont look at fancy fishfinder types with wide scan sonar etc.

The chart plotter needs to be one with sonar/depth sounder capability and will need the depth sounder unit, the plotter could have internal GPS built in or use external GPS antenae.

then its just wiring them up, simples.

I presume you know about changing to adjusting the MMSI number on the vhf set ? if you have a new mmsi number to program in you may have to take vhf set to a service centre to clear the old number.

Poly · 03 June 2019, 07:20

Quote:

Originally Posted by boristhebold

I presume you know about changing to adjusting the MMSI number on the vhf set ? if you have a new mmsi number to program in you may have to take vhf set to a service centre to clear the old number.

The MMSI stays with the boat so no need to reprogram. If you were removing that cobra to reprogram it would probably be almost as cheap to replace with something modern (that might have its own GPS built in).

Just to give another option - if you wanted to get one of the “non 0183” plotters you could add a separate GPS feed just for the radio. That offers some redundancy in that you then have two independent sources of GPS position.

TWPC · 04 June 2019, 21:04

Thank you very much for those replies, boris and Poly.

I see that some chartplotters such as the Simrad and Lowrance Hook 2 include a 'basemap'. Are they functional or do I need to spend another £150+ on maps from CMap or Navionics? I will only be using the boat around the Solent.

TWPC · 04 June 2019, 21:06

Quote:

Originally Posted by Simonh66

I have the Garmin on my RIB, great little unit

Simon, I got it wrong in my first post: it turns out the Garmin does NOT come with a transducer.
What transducer do you use with your unit and are you happy with it?
Thanks,
Tom

Poly · 04 June 2019, 22:14

Quote:

Originally Posted by TWPC

Thank you very much for those replies, boris and Poly.

I see that some chartplotters such as the Simrad and Lowrance Hook 2 include a 'basemap'. Are they functional or do I need to spend another £150+ on maps from CMap or Navionics? I will only be using the boat around the Solent.

The basemap will show you that you are in the UK, possibly even a very rough outline of the coast, but usually no useful detail like rocks, lights, depths. Shopping around they will often be available as a bundle with a map, as I recall it was basically impossible to buy the garmin without the map.

Tim M · 04 June 2019, 22:56

Plenty of good deals out there which include the charts. I've bought a Raymarine and Garmin plotter of late; both came with charts. The base map is virtually useless.

boristhebold · 05 June 2019, 06:49

Quote:

Originally Posted by Poly

The MMSI stays with the boat so no need to reprogram. If you were removing that cobra to reprogram it would probably be almost as cheap to replace with something modern (that might have its own GPS built in).

Just to give another option - if you wanted to get one of the “non 0183” plotters you could add a separate GPS feed just for the radio. That offers some redundancy in that you then have two independent sources of GPS position.

The MMSI number you say stays with the boat, well not always, you also need to check what information is held on the current MMSI number in use, it may be the boat is registered under a different name and owner and different contact details etc etc.

TWPC · 05 June 2019, 19:32

Thank you all for your advice.
I decided to buy the Garmin Echomap 65cv. Fingers crossed it all works properly and the VHF doesn't now go and expire!

ShinyShoe · 06 June 2019, 00:11

Quote:

Originally Posted by boristhebold

The MMSI number you say stays with the boat, well not always, you also need to check what information is held on the current MMSI number in use, it may be the boat is registered under a different name and owner and different contact details etc etc.

The MMSI belongs to the boat.

People do daft things. But there is no logical reason to take it with you when you sell if you leave the radio.

Yes - you need to update ofcom with the contact details. That's free.

And there is no way that set uses NMEA2000 unless Cobra developers have been on an episode of Dr Who.

Simonh66 · 06 June 2019, 06:56

Quote:

Originally Posted by TWPC

Simon, I got it wrong in my first post: it turns out the Garmin does NOT come with a transducer.
What transducer do you use with your unit and are you happy with it?
Thanks,
Tom

I just bought the basic one £50ish with a view that we could up grade if we wanted to. Works fine for depth etc. Not tried it for fish finding yet as that’s my lads thing & he hasn’t been out lately. I’m on the Hamble if you want to see it in action at some point

TWPC · 06 June 2019, 07:17

Quote:

Originally Posted by Simonh66

I just bought the basic one £50ish with a view that we could up grade if we wanted to. Works fine for depth etc. Not tried it for fish finding yet as that’s my lads thing & he hasn’t been out lately. I’m on the Hamble if you want to see it in action at some point

Great; that's the one I ordered in the end and depth is all I really need so thanks for the confirmation.

Hope your son has success with his fishing when he gets the chance.

Last Tango · 06 June 2019, 07:32

Quote:

Originally Posted by boristhebold

The MMSI number you say stays with the boat, well not always, you also need to check what information is held on the current MMSI number in use, it may be the boat is registered under a different name and owner and different contact details etc etc.

I think if you contact Ofcom with your details they contact the previous holder of the MMSI and if they don't respond within a given time (months) the number transfers to you.