About Ben Ellison

Ben Ellison is electronics editor for Bonnier Marine Group, specifically Yachting and Cruising World. He previously was electronics editor for Power & Motoryacht and SAIL, as well as a writer for Ocean Navigator. His blog posts appear courtesy of his website www.Panbo.com, which has 80,000 monthly readers worldwide.

Lowrance DSI , & Navionics goes MicroSD (Raymarine included)


Last week Lowrance announced the Elite-5 DSI and some related fishfinder/plotters, and while they’re unabashedly aimed at freshwater fishermen, there’s at least two things of interest to others.  DSI stands for DownScan Imaging, which seems to mean that Lowrance has isolated the high resolution down-looking portion of StructureScan into an even more inexpensive form.  That means a transducer that can ping at 455 or 800 kHz, trading detail for depth and breadth.  Aren’t lots of non-fishing boaters — like gunkholers and/or curious monkeys like me — also interested in detailed bottom imagery, even if it’s only to 100 feet or so?  That’s why I installed StructureScan on Gizmo even though the thru-hull transducer wasn’t ready yet, and I can’t wait to seriously experiment with it (soon!).  The new Lowrance plotters will also be the first I know of to exclusively use MicroSD chart cards…

The move from regular SD cards to the micro size is no surprise, but I didn’t realize that Navionics is already doing it, as indicated on its card catalog pages.  They very likely come with an adapter to fit regular size SD slots, so the transition may be pleasantly hard to notice.  But learning that Raymarine is also going to support MicroSD cards may be a very pleasant surprise for folks who may want to swap to Ray from an SD MFD, or vice versa, or want to carry an SD plotter as a backup to a Ray machine designed for CF cards.
   I’m not sure when the Raymarine CF-to-MicroSD adapter, and the needed software updates, will be available, or what it will cost, but according to this help page, all the C, E, and G series will be supported, and models that aren’t, like the early A’s, will get an adapter from Navionics.  Given that Garmin has been shipping charts on MicroSD cards for a while, are we moving to one standard card size for use in all MFDs and PCs?  Wouldn’t that be nice?

PS. Raymarine will include the CF to MicroSD card adapter with MFDs starting in September, and the charge to existing MFD owners will be $30.


SimNet network testing, & more NSE goodies


Years ago I gave Simrad grief for developing its own NMEA 2000 cable and connector system, called SimNet, instead of going with the DeviceNet standard as NMEA wanted.  When NMEA 2000 was just getting started, SimNet confused end users and installers alike, as would Raymarine’s SeaTalkNG, and Lowrance’s first version of LowranceNet, etc.  I remain leery about proprietary cabling but I’ve never heard of performance issues with SimNet, and I’ve never had any trouble integrating SimNet devices into standard N2K networks, using male versions of the adapter cable seen above.  Until this week, however, I’d never tried it the other way around, building a SimNet network and adding in other manufacturer’s N2K devices as desired.  No problems so far…

The thin cables certainly are easy to snake around a boat and the connectors aren’t even threaded (though they plug together with reassuring snugness).  I was also pleased to learn that Simrad has those inline connectors seen above (red with termination built in, yellow without), which nicely increase lay out possibilities.  There’s no such thing as SimNet field attachable connectors, mind you, and the cable really isn’t designed to be cut (as you can see here), but that’s not a bad limitation if you can run pre-made cables wherever you need them.  And if you check out the manual available at Simrad’s SimNet page, you’ll see that the rules about daisy chaining and even termination are pretty loose.  I know such looseness vexes NMEA, and I understand their desire to protect the standard, but has anyone heard of a SimNet install that failed to network data and power successfully?
   If there have been SimNet failures, and we might hear about them in comments, I’ll bet they involve extra large networks in which the nuances of N2K — like voltage drops and impedance distortiions — can get critical.  As you can see below on the NSE12 device list, Gizmo’s SimNet is pretty simple so far, but I intend to challenge it in the months ahead.  Simrad is suppossedly going to let me try a AP28 autopilot system, whose head unit, compass, rudder sensor, and processor are all SimNet.  Plus I’ve set up Gizmo so I can fairly easily replumb any device from the standard N2K backbone to SimNet, as I did below with the Garmin AIS600 and Maretron DST100.
   There are reasons why even a vessel with a lot of Simrad equipment might choose to go with standard NMEA 2000 cabling.  If Simrad’s SimNet parts inventory is low, as seems to be the case these days, there are no alternatives.  And if a boat’s network grows to extra large size, I suspect that NMEA 2000 certified cable and connectors — especially split power taps and MID size cable — are going to serve better.  The cost of SimNet pieces seems a little mysterious, too, as indicated on this West Marine page, which shows three different prices for the same seven pin multiport, ranging from terrific deal to nearly outrageous!  Personally, I might try to, say, use a 10m section of SimNet cable in an otherwise standard backbone because it made fishing the mast much easier, but I’d treat it as experimental (in fact, I will experiment with that).  Of course the main reason someone would choose SimNet is because they are going with an all (or mainly) Simrad system, which is becoming a compelling choice…

Gizmo_SimNet_cPanbo.JPGOne pleasant surprise I got when I fired up the Simrad gear on Gizmo’s rebuilt flying bridge dash was how the IS20 and NSE12 share data source configuration.  When I put the former into auto select mode, the latter came along for the ride (as you can see below), and changing a specific source (when I added in another heading device) on one unit changed it everywhere.  I think that you can bypass common sourcing, if desired, using SimNet “groups” but haven’t tried that yet.  (I also think that this integration would work fine over standard N2K cabling, because the devices can’t tell the difference, but, interestingly, that is not necessarily true of Raymarine SeaTalkNG, which contains a sixth wire that Ray devices can apparently use to determine cable type.)
   Of course, the more important stuff is beyond the small data networking, assuming that works OK, and I’m sure liking what I’ve seen so far in NSE software 2.0, like the Insight chart improvements already discussed, plus the enhancements the BR24 Broadband Radar got with an easy-to-do update.  (You can download an interesting Simrad PDF about all 2.0 improvements here.)  I haven’t tried BR True Motion yet, but the 36 rpm mode definitely improves visual and MARPA tracking at close ranges…

Simrad_SimNet_on_Gizmo_cPanbo.JPGI also like the crumb trail option for MARPA targets, seen below as the daysailing schooner Surprise transits the now infamous channel through Camden’s Outer Harbor.  And I’m beginning to think that the NSE’s target acquisition algorithm helps a user pick moving targets in a field of stationary one’s like Camden’s mooring fields…or else I’m a very lucky target picker.  The Garmin 7212 is also now fully installed on Gizmo, soon to be followed by Raymarine E Wide and Furuno NN3D MFD, and the real testing/cruising regime is slated to begin late next week.  I’m hoping to uncover lots of pleasant surprises, but I’ll close with one more NSE tid bit…

Simrad_NSE12_marpa_crumbs_cPanbo.jpgIn the screen below, the NSE is showing output from a Raymarine Cam100.  I find the Menu Key and Rotary Knob control of all those options quite easy, and you’ll find similar context specific menus for every different screen or window.  I particularly like that Mirror Image control, which is pretty unusual I think.  This specific Cam100 — which I find quite sharp, and also has a limited low light mode — already outputs a mirror image so it can be used to look aft when you’re facing forward, like a car mirror.  But I haven’t yet figured out how I prefer a camera to look aft, plus I’m looking for ways to flex mount the Cam100 so it can do different jobs in different situations.  The NSE, and any other MFD that can flip video input, will help.


SRT mini AIS modules, & trouble from the East?


I mentioned SRT’s amazingly miniaturized Class B and SART AIS modules back in May, but seeing is believing. In that aluminum EMI enclosure at left is a Cobalt Class B transponder complete with precision GPS engine and power supply (the board itself is inset)!  What we’re looking at is smart phone technology applied to a very specific marine use, and it shouldn’t be too long before these modules make AIS less expensive, more powerful, and much easier to integrate with other devices.  But I’m also hearing about a dark cloud looming as the marine world rapidly adopts AIS…

I once got my hands on something called a Smart Radio SR261 {absolutely no relation to SRT} and discussed how this cheap but uncertified transponder might cause real problems with the slot sharing scheme that makes AIS work well.  Several readers with a lot of AIS expertise agreed strongly, and I’m glad not to have heard much about the SR261 since.  But now there appears to be a problem with AIS testing firms outside the U.S. and Europe that don’t actually test transponders correctly.  I’m told that Samyung, Haihua Electronics Enterprise, Shanghai
, and Alltek Marine have all secured local approvals in South Korea, Taiwan, or China for
Class A and B transponders that have all failed testing at the facilities (TUV and BSH) approved by the US and EU.  {Correction, 7/15: Alltek’s Camino 101 Class B transponder passed BSH testing in March, got CE certification on June 30, and should get FCC approval very soon.}  Apparently they are not always capable of adhering to the AIS slot mapping protocol, and could step on other transmissions.  That’s not good, and it may be difficult politics for the IMO to get all member nations to police their own testing firms.
   Ships and yachts wander the globe, which is marvelous, I think, but also means that one nation’s regulatory laxness can cause trouble anywhere.  So on top of known AIS issues — like older Class A’s that can’t decode the B static data message, and ships that don’t pay much attention to AIS anyway — we have to worry about faulty transponders.  Damn.  The least we can do is to discourage bluewater sailors from buying transponders that lack US or EU certification.  For an example of how rigorous that testing is check out the files posted when SRT’s Class A unit was approved in May.  I’ll close with a shot of SRT’s developement lab in the U.K.; isn’t it comforting that the gentlemen who created those nifty-looking modules above are nearly as ‘mature’ as many of us?


Camden NOAA chart changes, the questions


So I’ve done more research into the various small issues I’ve noticed regarding recent NOAA chart changes to Camden Harbor (discussed most recently here).  Let me emphasize small, and also my appreciation of NOAA as an agency with vast tasks and limited resources.  The intent of charting the Outer Harbor channel buoys maintained by the town, and updating dock details in the crowded Inner Harbor, is excellent; nearly every day I’m around the harbor I hear visiting boats getting guidance about these matters via VHF, and the verbal guidance often doesn’t work well.  But the chart update issues certainly bring up questions about data sourcing and NOAA’s quality control system, as well as others regarding intentional and unintentional chart presentation details.  And they probably apply to the official charts all around the country…

If you click on the top picture, you’ll see what the channel looks like now, as seen from its outer end.  It’s darn straightforward (aside from the fact that you can’t see where it starts when entering the harbor), and it’s looked generally like that for decades, though I think the Harbor Master may have adjusted the buoy lines slightly during some spring settings, seeking maximum width without any of the moored boats swinging into the channel.  (He has the buoy and mooring locations all databased on a plotter and in a PC charting program.)
   At any rate, I ran close along both buoy lines last week, marking the red and green balls as best I could (though not realizing that some of the no wake buoys are also charted as cans and nuns), and you can see the results below.  I was surprised to find that the newly charted red buoys largely reflect reality and that the channel is indeed offset from the Special Anchorage Areas boundary lines that are supposed to define it.  I hadn’t noticed that before and don’t yet understand it, as the Harbor Master created those lines himself during the long process of having the Areas officially approved.
   But one thing I’m 99.9% certain of is that the green channel buoys have always been in a line and that line has never been near the charted location of #13, which is way into a field of granite mooring stones that rarely get moved.  Or even #15.  Apparently the party who charted these so-called “private aids” was either the U.S. Coast Guard or members of the USCG Auxiliary or Power Squadron working through something called the
Cooperative Chart Updating program (mentioned at the bottom of this NOAA page), and I understand that plotting mistakes get made.  What I don’t understand is how this channel buoyage got through a quality control process.  Have you ever seen a channel buoyed like this, especially one running through an area of consistent depths and no hazards?  Shouldn’t a cartographer have questioned it?

NOAA_13307_ENC_with_actual_bouy_marks_cPanbo.JPGI also don’t understand what happened to the “Priv aids” label prominently displayed on the new paper chart (and RNC below) when the new ENC was created.  NOAA says it has no control over how ENCs are displayed, which is true, and that’s why I put Coastal Explorer in full detail mode above, and opened the ‘options’ box indicating that “Show All Chart Text” is enabled.  So is CE somehow ignoring a “Priv aids” label or did it not become part of the ENC database?  If not, why not?  (Note that if you dig into the ENC buoy properties you’ll see “Status:private” info, but it takes some digging.)
   I’ve also learned that NOAA’s policy is that “All aids, regardless if private or federal maintained, are depicted using the US/internationally recognized symbology” but I question that too.  It seems to me that older charts used to graphically differentiate official buoys from private ones, which is generally true to reality.  The reality that all those numbered cans and nuns above are in fact unnumbered round balls or even “no wake” pylons seems like a good example of why such a “uniformity” policy can be confusing.  And why the “Priv aids” label is a valuable tip off to a fog bound navigator.  Now to the Inner Harbor…

NOAA_13307_with_actual_bouy_marks_cPanbo.JPGAn interesting thing about the first 1:20,000 scale Camden ENC is that all those docks at the head of the harbor are not copied from the equivalent paper/RNC, but instead represent a fresh survey by someone.  And for the most part the Public Landing at lower left is very faithfully represented.  Gizmo really was alongside that particular drop off float when I took that “New Mark”.  But the pier I clicked on in CE does not exist (and never did exist), which is easily seen in many available satellite photos…

Camden_new_pier_cPanbo.JPG…like Google Map’s below.  Note, though, that the Google photo predates the big changes that Wayfarer Marine made to its marina area seen on the upper part of both images.  The ENC representation is much closer to ground truth, even if it doesn’t reflect the extensive dredging that’s taken place over the years (why all the yachts in those slips don’t actually go aground at low tide).  I know I’m quibbling over minor details, but, gosh, if you’re going to this much chart updating trouble, why not go a bit further to get it right?…  

Camden_Inner_Harbor_Google_Earth.JPGAfter all, these charts represent the official source data, which will be slowly but
surely copied to all the commercial charts because it is the official
data.  And while I know that there are numerous corrective processes in
place, I’m a little leery about how long they’ll take.  I just got an
email response this evening to my discrepancy report of June 29, and all
it says is that a question about the buoy locations and numbers (as if)
has been sent to the USCG.  Which corresponds to this rather Catch 22-like statement I
got separately from a NOAA regional representative:

for the inaccurate position of the aids, NOAA charts what is known. NOAA looks to the US Coast Guard as the authoritative source for Aids to Navigation. The maintenance and movement of Private Aids is generally not reported to the Coast Guard once they have been established.  Therefore, the Coast Guard has no update to report to
NOAA for charting action.

I’m wrong, but I think that good old non-existent Can 13 is going to stay on
the Camden Harbor chart for a while because…well…now it’s official.

RMC Island 40, off the grid house boating


That somewhat odd looking “waterborne structure” is Robinhood Marine Center’s first Island 40, designed to give renters who may only have small boat skills a wicked nice Maine cruising harbor experience, as in swinging on a mooring with seals, osprey, lobster men, and cruisers for neighbors, with good exploration possibilities in all directions (and with a pleasant “destination” marina nearby).  And it’s a hoot!  I’m sitting at the Tessie Ann’s spacious aft dinette right now, enjoying a cool sea breeze and the use of a well thought out battery/inverter/solar panel system…

Seeing how the Island 40 is set up for a week at a time on a mooring (between renter turn arounds, when she’s towed in to the floats) is interesting for a cruiser like me with power issues, but a renter doesn’t need to understand much about the systems.  In fact, the operating manual says to leave them all on, even the ProSine inverter below, which draws virtually no 12v unless it senses a load. (That was a slight problem for my netbook power block, which kept cycling the ProSine on and off until we added another small load.)  The propane-powered heating, cooking, and refrigeration systems, normally seen on RVs, are unfortunately not suitable for a real boat, because they work well and fairly efficiently (I think).  
   At any rate, Andrea and I spent a complimentary weekend on the Tessie Ann because I expressed so much enthusiasm about the concept when it was unveiled at Maine Boatbuilder’s Show in March (and because I’m going to write about it in Maine Boats, Homes & Harbors).  Despite some wet weather, my enthusiasm remains.  I believe that a big portion of boat enjoyment is just being in places like this, and the Island 40 is a heck of lot more comfortable than many boats.  I’ll add some more info and photos when I get home, but take note that this first season, you can rent this for as few as three nights, very reasonably too.  Highly recommended!
IMG_8351.JPGPS  The Tessie Ann comes with the use of the fine 15′ outboard and rowing skiff seen below, but it would be great to bring along your own kayaks and/or a larger outboard.  Both sides of the Island 40 are set up for tying off small craft, in fact, and Riggs Cove is central to all sorts of shallow and deep water cruising, striper fishing too.  While you don’t have to be an experienced cruiser to enjoy this vessel, many will appreciate how trouble free and comfortable it is, and also the gentleman responsible for this unusual concept…

RMC_Island_40_skiff_cPanbo.JPGThat would be Andy Vavolotis, who founded and ran Cape Dory Yachts for some 28 years and 2,800 sail boats, and has now owned Robinhood Marine Center even longer.  And he’s never stopped building things, as can be seen in RMC’s fun and historic out buildings, and the wild array of multihulls hanging from the ceiling of one large storage shed.  The skiff and the Tessie Ann, named after Andy’s mom, are the latest, but certainly not the last.


Garmin 7000 and AIS 600, some install details


Today I checked out some just-received Garmin gear prior to installation on Gizmo, and I noticed some nice little changes.  For instance, this AIS 600 has an automotive blade fuse instead of a glass cartridge and its relatively flimsy holder (which should all vanish from boats, I think).  And Garmin’s included NMEA 2000 cable is thicker than it used to be, indicating, I’d guess, some added EMI protection (needed to get NMEA certification, pdf on that subject here).  Garmin has also started using separate split screw collars — seen on and off in the photo — on lots of connectors besides Ethernet, which means easier to run cables (in some situations).  Note, too, the most LED indicators I’ve ever seen on a Class B transponder.  Tentatively speaking, the thing seemed to work pretty well too…

I had a little trouble with the 600′s USB drivers, probably due to the decrepit XP laptop I was using, and couldn’t get the installer software to write an MMSI, etc. to the transponder.  Hence it’s only in receive mode now, but Coastal Explorer did recognize the troubled port and showed A and B targets at good distances.  The Garmin GPSMap 7212 I also received got the same A and B targets, all static data included, over N2K.  (As you may recall, earlier NMEA 2000 displays and transponders got a little messed up because not all the standard messages were created in a timely manner; hopefully that’s getting straightened out, and I’ll sure have a chance to find out in the coming months.)
   Meanwhile all of the 7212′s cables, Ethernet excepted, have color coded right angle connectors, including a (thick) 2 meter N2K cable that would be useful in lots of installs.  I also liked the included stick-on template, which made cutting Gizmo’s new Azek expanded PVC flying bridge dash easy.  And check out the detail at the lower left of the photo below.  You can not only screw fasten the 7212 from the face side — which has thankfully become the standard — but by using those threaded “ears” you can even bolt it from the face, which would be stronger and would hold up better to repeated pull outs.  The 7000 series is heavier and deeper than its sibling 5000 series, but doesn’t look huge compared to its competition…

Garmin_7212_back_and_template_cPanbo.jpgI don’t suppose these photos below do quite the job of actual size specifications, but isn’t it interesting to see the backsides of what are arguably the four top gun MFDs of 2010?  They are, of course, the Garmin 7212, the Simrad NSE12, the Raymarine E140 Wide, and the Furuno MFD12, and they’ll all be on functioning on Gizmo sometime next week, hopefully (and should have been already ;-).

MFD_top_guns_2010_cPanbo .jpgAt heart, these MFDs are all dedicated PCs, but don’t these shots say something about build quality and water-tightness, not to mention the cooling of bright screens and hot processors and — maybe most important — dedicated marine connectivity?

MFD_top_guns_2010_tilt_cPanbo .jpg

Paneltronics AC load shedding, smarter power

Paneltronics AC load shedding module.jpg

Paneltronics new load shedding system is somewhat related to my battery/monitor/charger travails.  Boaters of all sorts are struggling to manage their electrical appetites, and the line between electrical and electronic is getting fuzzy indeed.  And there are all sorts of us; I have no need for AC load shedding personally, though this device is unique in that it’s aimed at boats like Gizmo

The Paneltronics power management system is only $689 MSRP and it’s only designed to manage a 30 amp shore service, shedding up to three loads before the dock circuit breaker trips and turning them back on again once the excess load has gone away (assuming, I guess, that they will go on again by themselves when power is restored).  In other words — heat wave on the East Coast! — you wouldn’t have to get out of your deck chair after the ice-maker kicks in and knocks the AC, inverter, etc. out.  It can also manage 30 to 75 amp generator loads.
   Load shedding is already a feature of some distributed power systems, like Moritz’s OctoPlex seen below, but those are whole boat systems, not add-on modules like the Paneltronics design.  And there is another approach to this issue, which is a synchronized inverter that can use a boat’s batteries to get through peak loads.  I think Victron pioneered this technology, and Nigel Calder has proselytized about it in Ocean Navigator and Professional Boatbuilder.  Reducing generator size is a good thing, whether done with battery assistance or load shedding.  In fact, I heard an NPR radio interview today (available here) discussing ways whole national power systems could be made much more efficient thanks to a central systems for managing home and business loads on a grand scale.  Check out the Demand Response and Smart Grid Coalition.  Electricity is definitely getting more electronic, at all sorts of scales.


Gizmo 12v power issues, dumb questions?


There’s no such thing as a stupid question, right?  Please?  Above is the only label on each of Gizmo’s main bank 8D batteries, and though it says AGM in big letters upper right, I’m not completely sure that they actually are Absorbed Glass Mat batteries.  Can anyone confirm one way or the other?  Then I might have a better sense of how well my battery monitoring system is set up, and what it’s telling me…

Last season I mostly judged Gizmo’s state of stored power using battery voltage, as I wasn’t sure the Xantrex Link 1000 below was showing a true amp hour deficit figure (especially after this forum thread), and was not even sure what the total available amp hours were anyway.  I’m still not sure about the size of my AH bank account, to be frank, but I now think the -230 figure shown below is in the true deficit ballpark as I got it to about zero after extended charging via a Xantrex Freedom 2500 while the boat was hauled.  Typical voltage at this deficit state is 12.45v, though if I run the main engine with its 130 amp alternator, or the 6kw generator, battery voltage will hold for a while at about 12.65, even if I haven’t chipped away much at that deficit.  Any red flags going up amongst the battery cognizanti out there?
   The big truths are these, unfortunately:  I know nothing about the history of this battery system prior to March, 2009;  Gizmo’s former owner mostly kept the boat on shore power, anyway;  I almost never have access to shore power, haven’t been cruising extensively yet, and hate running the noisy generator (another issue to be investigated); and I’m pretty dumb about batteries/chargers etc. overall…which is probably obvious.  For instance, am I doing serious power misering at the float just because I don’t run either engine or generator enough, or because neither is charging the way they should?  The alternator seems to push about 60 amps for a brief period, than about 30-40 and the latter about 30.  Would the never-installed battery temp sensor for the Freedom 25 make much difference?
   I’ve gotten intrigued with adding a couple of solar panels so I might maintain a near full battery bank and still be moderately profligate with 12v when the boat’s at home on its float.  But I’m also wondering if these batteries may need the equalization I understand is possible with AGM batteries, if they are AGM batteries??

Gizmo_Xantrex_Link_100_cPanbo.JPGI’m also trying to track down what seems to be a .5 to 1 amp current flow through the Link 1000 when every switched circuit is off but the main battery switch is on.  I’ve found a few unswitched circuits but none tested seems to the culprit.  Can a clamp meter (I don’t have yet) read low enough to help find the amp hour thief?  Also, if I cable whatever solar charge controller I get through the shunt below, will I be able monitor its output via the Link 1000 and its own monitor?  Sorry to be a font of possibly dumb questions — and promise to write about something I know more about soon — but, then again, I suspect a lot of Panbo readers are, like me, more tuned in to their electronics than the electricity needed to run them.  Guidance will be appreciated from those of you who have figured this stuff out.  


Panbo logo, & Gizmo lit for the 4th

Panbo Logo draft.jpg

It’s just a draft  — artist I’m not — but maybe someone out there in Panbo land can craft this into something fun for a hat and business card?  The graphic idea is an electronic wave turning into an ocean wave, but I’m open to another design…as long as it floats some boats.  Seriously, the first hat (a nice long-billed, cotton khaki cap) will be yours, plus my undying gratitude.  (If it would help to start with my draft creation in vector form, you can download it as an .ai file.)  Homework is completely optional, of course, and you, like me, may have a holiday to celebrate…

I’m hoping to attend the Camden Harbor 4th of July fireworks in style.  Yesterday evening I finally completed the crawl-and-grunt work needed to power up the two OceanLED Amphibian A6′s mounted on Gizmo’s transom, and I’m pleased with the look.  I chose “warm white” for the color, though the OceanLED office in Ft. Lauderdale suggested otherwise (blue, or maybe bright white, is how’s it done down there).  But I didn’t want to be too obnoxious in an olde New England harbor where underwater lights are almost never seen, and now it’s looking like warm white nicely brings out the green in the water (click on the picture).  I also put the test meter in the line and can verify that the two A6′s put out a lot of light for 12 watts total.
   You can also see the SolLight RailLight Mini on duty, now shifted to the starboard side of the flying bridge, plus the new, and brighter, Premium model mounted at the tip of the boom, both in an effort to light up the flag.  I could see the Premium four LED shine all the way to the head of the harbor as I rowed home, and think it would function fairly well as an anchor light.  At any rate, I’m looking forward to a post fireworks promenade around the harbor, and a few days off, and wish you all a fine holiday too.


Maretron DSM250, N2K ups & downs


There’s a lot to say about this screen and how the values got there, or didn’t, but what I like the most is how Maretron’s DSM250 is displaying the outputs of two NMEA 2000 depth transducers at once, and that I was even able to name their data windows in an informative way.  I think the screen will be useful in some tight gunkholing situations, and would be even more so on a larger vessel or a multihull.  Unfortunately this level of N2K data management is not yet available elsewhere, unless I’ve missed something…

Most of N2K displays I’m testing let a user choose the source of a particular data type if there is more than one on the backbone, but they don’t let you show two of the same type, except for items that are commonly multiple like engines and tanks.  Some Lowrance MFDs are an exception, but I’m not sure that feature migrated to the HDS series (I’ll check), and I recall that it did not apply to depth for some reason.  So you can often get double depth read-outs by setting different displays to different sources, but maybe only Maretron supports the screen above.  The trick was to change the “Instance” of one transducer from the default “0″ so I could then select different instances of Depth when setting up the screen.  Not every manufacturer gives you the ability to change Instance, though Maretron is great about it, and you almost invariably need a same manufacturer display or software to make the change.  Instances is one of those areas of N2K that most users will never need to know about, and I find confusing, but it seems to have powerful possibilities.
   “Labels” is another one of those areas.  Frankly I don’t even know if they are a mostly-unused N2K option, or only a Maretron feature.  But they’re definitely cool when they work.  As you can see on this N2KAnalyzer screen, many Maretron sensors accept Labels.  You can type them right into Analyzer for storage in the sensor and then when you’re building a screen on the DSM250 or in N2KView you can simply use the custom label as a data description.  Unfortunately, the oldish Maretron DST100 I’m using doesn’t support this feature and I had to resort to the DSM250′s custom name feature (below), which is nice to have but painful to use.  Do not tap away at those four keys to painstakingly write a long description and then just Back out without going to “Save & Exit”!  Maretron also doesn’t seem to recognize the DST2000 I mounted near Gizmo’s bow as something it can configure, which seems odd as Airmar built the DST100 as well.  (That transducer, incidentally, works better than many predicted, holding 300 feet of bottom at up to 14 knots in testing so far.)  A Garmin MFD can set a keel offset on the DST2000 (also called the DST800, I think), but I found that both it and Maretron got confused about such configurations if both transducers were online at the same time.  So it goes.
   Now about the Simrad AP 11 heading and rudder data seen and not seen in the top screen.  At first I thought I could use a Maretron RAA100 adapter to get the latter, but it turns out that Simrad used frequency instead of resistance for its pre-N2K rudder sensor, and the RAA100 can’t translate.  So instead I wired a Simrad AT10 to the AP11′s NMEA 0183 port.  The latter is supposed to output rudder data and the former is supposed to translate it, but, as you can see, the DSM250 isn’t showing it.  But it is now getting heading info from the AP.  So it goes.