Which GPS? HDS-5m, CP300i, 551

[winsbury]

It looks like this could run and run and possibly with no distinct favourite or reason to/not to buy a particular brand. Its certainly interesting that very few moans have been aired so far which leads me to think most of the plotters at this level can do the intended job with some minor caveats. My inclination is increasingly for the Lowrance unit as the screen is square so largest of the group and makes 'heading up' settings easier to read ahead and the resolution is so much higher than the others so should show more details too. I'm not too worried by complex menus as I'm reasonably computer literate and intend to continue to use paper charts to plan in advance although the Navionics charts look like they can be loaded on a pc for planning purposes too - does anyone use the Navionics PC software ?

 

[maby]

It looks like this could run and run and possibly with no distinct favourite or reason to/not to buy a particular brand. Its certainly interesting that very few moans have been aired so far which leads me to think most of the plotters at this level can do the intended job with some minor caveats. My inclination is increasingly for the Lowrance unit as the screen is square so largest of the group and makes 'heading up' settings easier to read ahead and the resolution is so much higher than the others so should show more details too. I'm not too worried by complex menus as I'm reasonably computer literate and intend to continue to use paper charts to plan in advance although the Navionics charts look like they can be loaded on a pc for planning purposes too - does anyone use the Navionics PC software ?

The Navionics PC software is not bad - there are aspects of the user interface that can be frustrating but once you understand it, it works OK.

It's probably not relevant at the entry level end of the market, but the thing which pushed us towards Lowrance (and the other Navico family) is the availability of broadband radar - the resolution and close-in performance are so impressive.

 

[winsbury]

Okay I've plumped for the Lowrance HDS-5M, so now to decide on DSC VHF and AIS.

Stupid me, I thought this would be easy - I want AIS receive only so surely a Standard Horizon GX2100 AIS DSC VHF has all the bells and whistles including foghorn and hailer - brilliant !... In my mind I though it would hook straight up to the plotter - ie send GPS signal from plotter to VHF and AIS signal from VHF to plotter - easy right ?... no , wrong, in spades. The HDS has a single NMEA port, so what I hear you cry, its duplex, nope, thats not the problem - It turns out that NMEA GPS signals run 4800 baud whereas AIS signals run at 38400 baud AND the Standard Horizon outputs DSC and AIS info on two separate wires. All this means that although the two bits of kit have all the functionality I desire they wont talk to each other without a multiplexer which adds another £200 to the bill, so much for integration saving ££££s.

I have come up with the following equipment lists which seem to give all the functionality :

GX2100 AIS/VHF £290 + Multiplexer £200 = £490
or
GX1700 GPS/VHF £200 + AIS Engine III £120 = £320
or
GX1100 VHF £100 + NASA AIS Radar £220 = £320
or
GX1100 VHF £100 + NMEA GPS Antenna £100 + AIS Engine III £120 = £320

As far as I can see theres no way to hook up a simple two device system that does everything, ie GX2100 to HDS5M unless anyone else has any bright ideas ?

 

[maby]

We bought a Simrad VHF (the one which has the cordless second-station) which is wired to the NMEA out of the HDS5 for the positioning data to drive the DSC functionality plus a Garmin AIS engine with NMEA2000 networking - avoids any speed issues in crowded waters and we get the AIS plots on both plotters (HDS5 at nav table and HDS8 at the helm) - not the cheapest solution, but very versatile and easy to install.

 

[prv]

NMEA is one way anyway, so can't you run position information from plotter to radio at 4800, and AIS from radio to plotter at 38400?

Maybe you could commission Angus to build you a YAPP conversion box for a lot less than £200?

Pete

 

[maby]

NMEA is one way anyway, so can't you run position information from plotter to radio at 4800, and AIS from radio to plotter at 38400?

Maybe you could commission Angus to build you a YAPP conversion box for a lot less than £200?

Pete

'cos the Lowrances have a single duplex NMEA0183 port - in and out at the same speed. We're NMEA2000 throughout apart from the positioning data to the DSC. Would have gone NMEA2k for that as well, but could not find a VHF with that at the time.

 

[prv]

GX1100 VHF £100 + NASA AIS Radar £220 = £320

That won't work - for some stupid reason the "Radar" model doesn't have an AIS output, just the display.

GX1100 VHF £100 + NMEA GPS Antenna £100 + AIS Engine III £120 = £320

You can get a standalone NMEA GPS for a lot less than £100, albeit not waterproof (mount below decks) and needing a couple more quid to convert 12v to 5v.

One of the advantages of the AIS radios is that you don't need to fit a second aerial - if you go for a standalone engine that's probably another £100 once you add cable, plugs, etc, plus the embuggerence of having to fit it. An alternative would be the Digital Yacht ANT200 - basically a rubberduck aerial with an AIS engine built into the base. I have one; works well.

Pete

 

[prv]

'cos the Lowrances have a single duplex NMEA0183 port - in and out at the same speed.

Well that's silly

I suppose it's down to the UART chips they use, which expect to be used for a bidirectional interface hence at the same speed.

But a bit of thought about how people would use their product should have revealed this pitfall.

Pete

 

[winsbury]

Exactly what I thought initially Pete - after a lot of searching around I found a diagram on Standard Horizons web site specifically for hooking up a GX2100 to the HDS series plotters which confirms it definitely needs an external mux. It seems ludicrous to me that an external device is needed when its obvious how many people will want to use it in that configuration, imho it defeats the object of integrating the AIS into the radio in the first place - I suspect its a plot to force us to choose a CP180i instead which has far more NMEA ports.

As much as I'd like to, I cant justify the extra cost to go for a full NMEA 2000 system so I'm coming round to thinking that the multi-box approach at least gives me some redundancy and when I eventually sell the boat I can strip all the goodies out for the new one and just leave the relatively cheap radio behind, especially since once the MMSI is coded into it its virtually worthless. Nevertheless I really was hoping for a more elegant solution.

 

[maby]

...
One of the advantages of the AIS radios is that you don't need to fit a second aerial - if you go for a standalone engine that's probably another £100 once you add cable, plugs, etc, plus the embuggerence of having to fit it. An alternative would be the Digital Yacht ANT200 - basically a rubberduck aerial with an AIS engine built into the base. I have one; works well.

Pete

Unless you are going for AIS transponder, you can usually get away with a single antenna anyway - any decent AIS receiver will include an antenna splitter. You can get a splitter that works with transponders, but that is quite a lot more expensive.

 

[winsbury]

I have an old rubber duck on the masthead which is going to be replaced with a decent 0db whip twig, so I can use the rubber one as an AIS-cum-VHF standby antenna. Personally I'm not too worried about the single antenna advantage though can see thats a big plus if you dont want a second antenna. After all, when you're speaking to the ship thats about to mow your divers down, it would be nice to see their course change on the AIS plotter while you haggle about whos in the right, with a splitter system theres no AIS received while transmitting voice.

 

[pvb]

Nevertheless I really was hoping for a more elegant solution.

It would be a shame to lose the AIS display functionality of the GX2100 by going for a lesser radio and, as already mentioned, the GX2100 only needs the one antenna. Perhaps the most elegant and functional solution would be to have a GX2100 plus a decent GPS antenna (something like the Evermore SA320 for £95). This would also give you redundancy on AIS display, plus redundancy on GPS data.

Of course, if you were in the USA, you could just buy the GX2150 which will interface effortlessly with the Lowrance, as it can receive the GPS data at 38400 baud. In fact, you can buy these on eBay for about £220 plus £40 shipping, so even cheaper than a UK-sourced GX2100. There's a chance you might have to pay VAT, but you might get away with it. In any case, it'd be a cheaper and more comprehensive solution. There's the small issue that the GX2150 is technically not legal for you to own (although strangely there'd be no problem if a US boat fitted with one visited Europe). The chances of getting caught are minimal - I've been using an "illegal" HX471 DSC handheld for years with no problems.

 

[winsbury]

Of course, if you were in the USA, you could just buy the GX2150 which will interface effortlessly with the Lowrance, as it can receive the GPS data at 38400 baud.

Okay that got me excited an dvery nearly pushed the 'buy it now button' - sense prevailed and I downloaded the manuals for the GX2150 and GX2100 and the pdf explaining the differences - you're absolutely right the 2150 seems to solve the problem. However looking through the International channel lists theres no M1(37) or M2 channels listed in the manual for EITHER version. I know someone who bought a US handheld and it didnt have these channels even when set to International mode so I think the problem is the European version is GX2100E with the E denoting the special channels, the online manuals only cover the US versions which hides this difference.

Ive fired off an email to Standard Horizon UK for advice and clarification and will update the thread when I hear back.

 

[prv]

It seems ludicrous to me that an external device is needed when its obvious how many people will want to use it in that configuration, imho it defeats the object of integrating the AIS into the radio in the first place - I suspect its a plot to force us to choose a CP180i instead which has far more NMEA ports.

Eh?

Why are you directing your ire at Standard Horizon when the problem is the Lowrance plotter only having a single port each way and a daft restriction that they operate at the same speed? I'm sure Standard Horizon would love you to buy a CP180i (which, as you point out, is more sensibly designed) but I'm sure they didn't sneak industrial spies into the Lowrance design office to delete ports off their competitor's product.

Pete

 

[winsbury]

The reason I'm asking SH is they are the only one of the two companies that potentially have the solution: they already market the solution in the US and publically state this is specifically for customers with single port plotters but for some reason have not put it on the UK version. Also rather oddly they dont allow their US customers to have access to M1/M2 when travelling to UK (I have since located the manual to the GX2100E which confirms the access to M1/M2 is ONLY on the UK sets.) If either of these problems is overcome then there is a solution for UK customers and I suspect both are simple firmware tweaks whereas to add extra NMEA ports to the Lowrance a) is impractical and b) is how Lowrance upsell to their larger models.

Bear in mind the single port issue doesnt just apply to Lowrance and the HDS5 does have NMEA 2000 whereas the SH kit does not. To my mind, the plotter is an investment that will come with me to my next boat and is considerably more future proofed with the NMEA 2000 port than the SH plotter. The Radio on the other hand is disposable, once its MMSI is entered its essentially locked to the boat (perhaps a good argument to get a cheap radio instead !)

 

[maby]

Eh?

Why are you directing your ire at Standard Horizon when the problem is the Lowrance plotter only having a single port each way and a daft restriction that they operate at the same speed? I'm sure Standard Horizon would love you to buy a CP180i (which, as you point out, is more sensibly designed) but I'm sure they didn't sneak industrial spies into the Lowrance design office to delete ports off their competitor's product.

Pete

I have to say that, having a degree in electronic engineering and having worked as a computer engineer in the past, plus being a radio amateur for the last thirty-odd years, I had never come across a single serial port that was capable of operating at different speeds on send and receive until I looked at some modern chart plotters!

 

[winsbury]

Actually it was common for a while though less so recently. Check out ITU V.23 which uses 1200bps / 75bps asymetric and was used extensively for terminals connected to mainframes in the 1980's for inputting in one direction and receiving pages of data in return.

 

[pvb]

However looking through the International channel lists theres no M1(37) or M2 channels listed in the manual for EITHER version.

Is having M1 or M2 absolutely essential for you?

 

[winsbury]

Is having M1 or M2 absolutely essential for you?

I have a SH handheld which has them and since these are only every used on low power then no they are probably not essential to have on the fixed radio. I'm not 100% sure there are no other differences though.

 

[BarryH]

I have the Lowrance. It took me a while to get used to it. It has lots of features I'd never use. Quite a powerful little piece of kit. The charts are easy to read and akin to the normal paper variant. You can reduce the amount of chart info displayed which "cleans up" the clutter on the screen.
When I got mine the charts of UK & Ireland were thrown in free. I'll be honest with you. I found that after a while I got distracted too much by the thing, especially at night. In the end I sold it on fleabay. Had it less than a year. Actually got a few quid more for it than I bought it for....result.

Quite happy to fll back on paper pencil and tide tables with a little basic hand held to double check my DR positions