Upgrading electronics

[jecuk]

So I am buying a boat which currently has a Garmin GPS, a log and a depth sounder. I am planning to go to either a Raymarine set of instrumentation and chart plotter or Lowrance.

Not being sure how this sort of stuff is wired on a boat, will I need to replace everything or will transducers likely still be usable for the log and depth?

Will the plotter integrate with the existing GPS aerial?

Or are we talking a major upgrade process?

 

[misterg]

Hello /forums/images/graemlins/smile.gif

The answer to your questions depends on how much money you have to spend, and what you want to achieve by connecting things together.

From what I understand, the transducers etc. are generally specific to one type of instrument, but there are times where you might get lucky (depth transducers can be cross referenced on the Airmar website). The transducers seem to be the cheaper half of the deal, though.

Do the current instruments work? If so, why do you want to change them? ("Because I want a matching row of shiney new ones" is a valid answer - it's your money /forums/images/graemlins/smile.gif).

The lowest common denominator for interconnetion is "NMEA" - this will allow your GPS to talk to your autopilot, etc. and is not brand specific. Once you get past this though, things do get brand specific, and you would need compatible instruments from the same manufacturer to do things like dim the back-lighting on all the instruments at the push of a button.

What are you fitting out ? Tiddler or Titanic?

A real expert will be along shortly...

Andy

 

[roly_voya]

Most systems will accept the NMEA output from the Garmin but its unlikely you will be able to use the log and sounder sensors - particularly the sounder. If the current ones work it could be worth keeping them as backup/cockpit display and adding the new stuff alongside with say a single multifunction head for wind, compass etc in the cockpit and the plotter at the chart table. Most networks are simple single wir plug and play systems now. The main difference seams to be in attaching any non-netwrok bits. For example with raymarine is you want to add a PC you have to run raytec software and have a plotter wearas Silver Nexus has an imput on the server where you just plug in an RS232 lead + any NMEA stuff which makes it much more versatile. Depends if you are going to do everything in one go all from the same company or have say a different make radar or want the option to add stuff later that may be from a diff make or even from a newer series.

 

[jecuk]

It is a classic 36ft wooden cruiser. The existing electronics are a touch messy and I want to get a modern chart plotter as I intend to do some UK and European coastal cruising. As the existing are recessed below a wooden cover, space for the instrumentation is a bit limited - I want to be able to replace the wooden cover for a more classic appearance when at trad boat rallies etc! As such, a single unit will be easier.

Not wanting to spend money for money's sake but sometimes it is easier (and cheaper) replacing the accessories rather than trying to get them all to work togehter if you are going to spend up on a bigger ticket item like a plotter

 

[wooslehunter]

It took me 4 years to replace the log & depth on my boat. I finally decided to do it this winter after someone ran into me & I need a fibreglass repair. The guy is also fitting the new transducers.

The problem being that unless you are replacing transducers with a similar size, you'll have to do some work to make the through hull holes bigger or smaller. In my case smaller, hence the reluctance.

Although mine were working , sort of, they weren't so good and very old. Speed (no log) - not accurate since the adjustment was super sensitive. Depth - absolutely fine above 10m, but no alarm. Would be nice in Chi Harbour but not having one does make you pay attention. Depth was good above 10m, sometimes not below 10m & just not there below 20m so following a contour was difficult if not impossible.

Displays for both were almost invisble at night.

So all in all, they weren't too good but I stuck with it for 4 years because I didn't want to mess with through hull fittings.

I replaced them with Raymarine ST60. Why ST60? I have a Raymarine tiller-pilot & wanted to add a wind instrument to interface to it. Close reach & close hauled are difficult with just the tiller pilot because of wind shifts backing the genny. I looked at ST40 and found that the wind instrument with a rotor rather than a vane wasn't liked by people on here - fine for power but not so good for sail. Other makes would have had a problem to interface with the tiller-pilot.

if I hadn't wanted the wind instrument, I'd have gone for the ST40, bi-data, or a NASA unit. There are lots of thers but they're more expensive.

Wiring together is easy with Raymarine. Everything links via Seatalk. You simply daisy chain the displays with a cable from one to the next carrying power & data. None GPS interfaces easily too with just a pair of cables for NMEA.

 

[boatmike]

You will find for log and speed that you can buy raymarine complete for about £80 more than just the instruments. If you have to but the transducers seperately they are about £130. Don't mess about. Fit the lot.

 

[misterg]

I've just seen that JECuk (the OP) has a wooden boat. It might be grandmother & eggs time, but I think you need bronze bodied transducers to fit to a wooden hull, rather than the ubiquitous plastic ones. I've no idea how much these are, but I bet they're a lot dearer, and probably less choice. In this case it might tip the balance towards trying to make something work with the existing transducers - can't just "drill a new hole & glass the old one up /forums/images/graemlins/smile.gif).

Another point with the Raymarine stuff and NMEA, is that you need to check exactly what / if each of the instruments outputs. Some don't talk NMEA at all, and you need a (relatively) expensive 'bridge' to translate NMEA to Seatalk (or whatever).

Andy

 

[Aja]

Bronze?

Not so. I've just removed a plastic 150hz transducer from my fathers wooden boat after 20 years use. Will be replacing it with another (NASA Clipper) depthsounder with std plastic transducer.

NASA do not supply bronze transducers with their depth sounders.

If you make the hole oversize by a few mm and seal the plank edges with epoxy this will stop any wood swelling and fill the gap with a generous amount of sealant which is allowed to set prior to final sweating up of nut, all should be ok.

Donald

 

[boatmike]

Re: Bronze?

Well yes, but I would agree bronze ones are far better in a wooding boat made out of trees....
The same applies. Buy new with the instruments and they are far cheaper than buying seperately later if the old ones don't work (which they almost certainly won't anyway)

 

[misterg]

[ QUOTE ]
....As such, a single unit will be easier.


[/ QUOTE ]

Ahh, is this the sort of thing you're thinking of?

As far as I can tell, you need an 'instrument' for each function, pretty much. (Log & depth are frequently combined, though). Each of these is connected to its relevant transducer, etc. Once you've got these, on anything other than the basic range of instruments, the information registered by these individual instruments can be fed onto a common communications bus, but the format is generally specific to the manufacturer. One can add something like the item above to access any of this information in a single display.

I presume you've seen the 'TackTick' instruments which are wireless & solar powered? Saves you drilling holes in your nice woodwork, and you can put them in your pocket if you want to go for the classic look. Not cheap though.

As you can probably tell, I've exhausted my knowledge on this subject now /forums/images/graemlins/smile.gif

Andy

 

[jecuk]

Yes sort of. More like this.

Wireless worries me on a boat.

 

[misterg]

[ QUOTE ]
Yes sort of. More like this.

Wireless worries me on a boat.

[/ QUOTE ]

OK - so I think what I said above pretty much stands. The 'datapods' that the description refers to seem to be 'blind' instruments that turn the transducer signals into the proprietary format. This sort of thing:

Where the connection to the transducer can either be a ST70 'pod' or an ST60 'instrument'. Looks like everything has to be new, or nearly new, though /forums/images/graemlins/frown.gif.

I've never used TackTick stuff, but it seems to be well thought of & reliable - If it looks like it'll do what you want, then why not post another question asking about its reliability / suitability?

Andy