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Computers That Thrive in Salty, Humid Environments?

Ever seen one of today's garden variety computers running on sea-going vessels? How about in other places where water, or salt water is a large part of the environment? Today's Ask Slashdot deals with 3 questions surrounding the construction of computer systems that can survive in such a harsh environment. What does it take to harden a PC to survive in such a place, and how much more expensive will it cost to make one? Are there other issues to worry about aside from the salt and the humidity?

To start us out, frostman asks: "A friend of mine is living on a sailboat, and would like to set up a nifty computer system. It doesn't need to be too powerful, but it should be small, rugged, fairly quiet, and cheap. He has a standard PII/400 mid-tower system he can gut for parts (400Mhz would probably be enough). He wants to do normal internet stuff, watch DVD's, listen to MP3's (with good speakers)... and he needs it to run on 12 volts when he's sailing. Any suggestions from the hardware gurus on Slashdot?"

websensei continues with this query: "I am about to become a full-time live-aboard on my sailboat. I'm in the process of selling all my machines and plan to spend about $2000 on a new laptop for the boat. I'll use it for work and play (movies, gaming, TV via USB TV tuner?) etc. Please share any advice/experiences relating to computing on boats or other harsh/damp environs."

And last, but not least, Alioth asks about fishes, not boats: "How about computers in fish factories? Not only do we have to contend with the room being jetwashed, but the atmosphere is very salty. I've been looking at stainless steel enclosures - what's their salt water resistance like, not just the stainless parts, but the parts that fasten the stainless parts together, not to mention being able to keep the computer cool as well (meaning it's got to vent somewhere)?"

46 of 422 comments (clear)

  1. Isn't obvious what this is for? by Anonymous Coward · · Score: 5, Funny

    The only people who want to compute in a saltwater environment are pirates.

    1. Re:Isn't obvious what this is for? by Loligo · · Score: 5, Funny

      >The only people who want to compute in a
      >saltwater environment are pirates.

      Well, he mentioned wanting to watch DVD's, so I guess he's looking for booty.

      -l

    2. Re:Isn't obvious what this is for? by UpperClassTwit · · Score: 5, Funny

      yep ... it's all documented in aaaarrrrrFC 1337.

  2. In the factory... by marklyon · · Score: 5, Informative

    In the factory, I'd look for something along these lines: http://www.industrial-computer-enclosure.co.uk/wat erproof_computer/waterproof_computer.htm

    --
    -- Mark Lyon http://www.marklyon.org
  3. fish factories? by tps12 · · Score: 3, Funny

    They make fish in factories now?

    Every time I think we've reached the end of human progress, someone comes up with something new.

    --

    Karma: Good (despite my invention of the Karma: sig)
    1. Re:fish factories? by bigjocker · · Score: 5, Funny

      They make fish in factories now?

      I believe they mean factories ran by fish ...

      --
      Life isn't like a box of chocolates. It's more like a jar of jalapenos. What you do today, might burn your ass tomorrow.
    2. Re:fish factories? by sharkey · · Score: 3, Funny

      factories ran by fish ...

      Actually, I think they're Japanese factories run by workers wearing fish costumes.

      --

      --
      "Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
    3. Re:fish factories? by PaxTech · · Score: 3, Funny
      Yes, and they sing a happy little song while they do it.

      "Knife goes in, guts come out, that's what Osaka seafood concern is all about.."

      --
      All movements for social change begin as missions, evolve into businesses, and end up as rackets.
    4. Re:fish factories? by User+956 · · Score: 3, Insightful

      Now, we must also accept that self-actualization is progress...And if you like Kant, erecting a society in which people can actualize themselves follows directly from the Categorical Imperative.

      That interpretation is quite relevant to Hegel's position of the achievement of true freedom as the litmus of human progress. That is, if you believe self-actualization and true freedom are one in the same.

      If indeed that's the case, then the spirit of a people provides the best evidence of progress, and can be best looked at as the essence of a state. When a people rises and falls, it is accompanied by its particular world-spirit, which is its consciousness of freedom. Every people has a different consciousness of freedom. Some peoples believe in freedom for all (man, as man, is free), why others believe in freedom for a few (some men are free, while others are not).

      Kant, Hegel, and Marx (hell, you can even throw Wagar in there) were all forward-thinking progressivists with interrelated theories on the symantics of human progress. Personally, I prefer the classicist dionysian interpretation in that man's destiny is to suffer and die as part of the larger, cyclical process of the perpetuation of mankind as a species. Man's destiny is cyclical, regressive, or a regressive cycle, but it's certainly not progressive, regardless of the popular illusion. Nietzsche put it best: "We say it is 'explanation' ; but it is only in 'description' that we are in advance of the older stages of knowledge and science. We describe better, we explain just as little as our predecessors."

      --
      The theory of relativity doesn't work right in Arkansas.
  4. Re:Finally! by Anonymous Coward · · Score: 3, Informative

    Kontron Mobile Computing. Manufacturers of rugged portable systems. www.kontron.com seems to be the overall companies homepage. Follow the KMC link. Their Revolution, an upcoming product, looks especially nice. Their 8000 series is designed for crazy environments.

  5. It'll cost you. by stealie72 · · Score: 3, Funny

    Hmm. I bet you take a normal computer, put the word "marine" in front of it, and charge 4x the normal price.

    (note: this also works with the word "aviation").

    --
    I don't have an anger problem, I have an idiot problem
    1. Re:It'll cost you. by shogun · · Score: 4, Funny

      Dont forget space rated, same as the above but 1000x cost and will be delivered 5 years after you need it.

  6. Laptop by msheppard · · Score: 5, Informative

    My friend lived on his boat for 2 years and used a Dell Laptop with no salt-water related problems. He treated it like he stole it too, not being very careful or anything.

    M@

    --
    Krispy Cream is people
  7. Ask Katz to talk to Junis by FortKnox · · Score: 5, Funny

    Remember, Junis (from Afghanastan) was able to bury a Commodore in sand for years (and you know how the heat is out there), dig it up, run it, get on the internet, and download movies with it!

    I bet he'd have GREAT advice for anyone that required running a computer in hot, humid environments (although he's more into the "desert" environment than the "water" environment).

    --
    Good quote, too many chars. Seriously, the slashdot 120 char limit sucks!
  8. It's not THAT hard.. by mattster999 · · Score: 5, Informative

    There are tons of regular computers onboard sea vessels, the way they get around problems is to make the environment where the computers are NOT like a boat. Air conditioning, for managing humidity and temperature goes a long way to keeping electronics happy. If you want something that can get salt water splashed on it, you're talking something different.

    Plastic is an obvious answer. It's resistant to water, salt, heat, etc.. Underwater camera housings are made out of plastic and work very well. For cooling, you can do a heatpipe arrangement with aluminum heatsinks on the inside and out.

    The USGS has built entire PC's that are made to reside underwater for days logging data - they put them in watertight aluminum boxes and bind the heatsinks to the sides. Works great.

    1. Re:It's not THAT hard.. by ahfoo · · Score: 4, Informative

      I live a few blocks from the beach on a tropical island where the humidity is almost always around a hundred percent and I find that power supplies go out like mad. The most important trick is to keep everything on constantly. The machine creates its own microclimate because of the heat it generates, but obviously it only works if the machine is kept on all the time.
      My advice to your friend would be to bring at least four or five fresh power supplies wrapped in dessicant if he's going to be using a desktop system. And even better is to have a small network on board rather than a single machine. Leaving the machine(s) on as much as possible is the simplest advice though. Even extremely moist conditions don't have much effect on an active desktop system, but you have to keep it active. Eventually salty condensation will kill your PSU if you let it power down all the time.

    2. Re:It's not THAT hard.. by LordWoody · · Score: 4, Informative

      The key here is proper use of dessicant. We put this stuff in large packs (2" square about .5 to 1" thick) in almost every enclosed electronics/electric space on ship (not just for items in storage, but actual use items) and check (and change if necessary) it on regular schedules. It soaks up moisture like it is going out of style. Just remember, do not eat (the dessicant). :-)

      --
      Never meddle in the affairs of dragons,
      for you are crunchy and good with catsup.
  9. Re:Finally! by bigjocker · · Score: 3, Funny

    A computer that can reside in my crotch!

    Are you referring to the "keep the computer cool" part?

    If so, then yes, we have a winner ...

    --
    Life isn't like a box of chocolates. It's more like a jar of jalapenos. What you do today, might burn your ass tomorrow.
  10. TNAC might have a good solution. by thesolo · · Score: 5, Informative

    Check out TNAC if you need computers which are resistant to harsh environmental situations. The computers are built into the displays for a single, tough unit, are available in pretty decent speeds (PII & PIII), and have good onboard components (USB, 10/100 ethernet, etc.) They also only use 5W in standby, which is good for houseboats, etc.

    P.S. No, I don't work for them.

    1. Re:TNAC might have a good solution. by mosch · · Score: 5, Informative

      Laptops like this one are nice too. A decent laptop with some anti-corrosion features, and most importantly, a transflective display, so you can use it on deck as well as below.

  11. Get a cheap laptop and a 12V car adapter by TwoStep · · Score: 5, Informative

    I used an older Sony Viao laptop (I think it is like a Pentium 150 or 200), and threw a bit more RAM in it. I then went out and picked up a universal 12V adapter, which can not only power the laptop but will charge cellphones and all sorts of things.

    If the laptop is cheap enough, having it die doesn't matter as much.

    The only other tip I would offer is to try to avoid a touchpad, as the one on my Viao really doesn't like wet hands. I would go for one of those nipple things or maybe a trackball (do they still even ship with those anymore?)

    There is some real nice PC navigation software, like Visual Navigation Suite, which hasn't crashed on me once and supports just about all the electronic chart formats out there right now.

    You might want to check out rec.boats.electronics, as they have a bunch of useful information there as well.

    Twostep

    --
    There are 10 different types of people in this world... those who understand binary, and those who don't.
  12. Mineral oil by MongooseCN · · Score: 4, Funny

    Does anyone remember the story a while back about the computer that was cooled by submersing the whole thing in mineral oil, then running the oil over air conditioner coils? Maybe something like that would work. With the whole system in mineral oil, there's no way water or salt could touch the system. The only problem is, how would you cool the mineral oil? Maybe drop a bucket of the stuff behind the boat in the cold ocean water. Then swap that with the stuff covering the computer when it starts to get too warm.

    Someone must have a link to the old /. posting.

  13. I think you missed the obvious by Spamalamadingdong · · Score: 3, Interesting
    This is the absolute perfect application for a water-cooled system. You just have to come up with a heat exchanger that dumps heat to the seawater outside, instead of the air. And it would be totally fanless, too!

    It would probably be a bit more realistic to find a manufacturer of a box which is conductively cooled to the outer (sealed) casing. That takes care of corrosion issues in the computer itself; the keyboard, mouse and display will have to take care of themselves, and of course you're going to have to use something like a USB floppy/CD drive to avoid penetrations through the casing.

  14. Not worth the additional cost by Matey-O · · Score: 5, Insightful

    If you're looking at using a laptop INSIDE the boat (out of the weather, mist, etc.) Then I wouldn't bother spending the additional money on the 'marine grade' systems. They're much more bulky, and quite a bit more expensive.

    Here's a little thought experiment:
    Buy a laptop for $1200-1400 with a combo DVD/cdrw drive, make data backups to CD, store CD's in water tight container.

    In two+ years when it starts to act flakey (corroding battery contacts) buy ANOTHER laptop for $1200 to $1400, rinse repeat.

    It'll take a long time to add up to the $5000-ish you'll pay for your first marine grade laptop.

    --
    "Draco dormiens nunquam titillandus."
    1. Re:Not worth the additional cost by bad-badtz-maru · · Score: 5, Insightful

      You are exactly right. I was the IS director for the largest resort in the Florida Keys. We had at least 40 computers within 20 feet of the ocean. We used marine-grade anti-corrosive spray on all the connectors and we used special weatherproof keyboards (only because the bartenders dispensed more rumrunners into the keyboards than into the customers' cups). Other than that, we just used regular PCs. Our machines lasted 2-3 years (many longer than that) and they never died due to anything related to salt-water exposure. Oh yeah, these machines were located in thatch-roofed bars (roof made of palm fronds) and we would come in after storms, pour all the water out of the machines, wait for them to dry out, and power them up. Corrosion is the only problem and that is completely eliminated with a serious anti-corrosive spray (no WD40, we used Corrosion Block by Pacific Corrosion Technologies).

      maru

  15. Former Litton Marine Systems Employee speaks. by BigBlockMopar · · Score: 5, Interesting
    Ever seen one of today's garden variety computers running on sea-going vessels? How about in other places where water, or salt water is a large part of the environment?

    Yes. Imagine HP Vectra computers on shock-proof feet to protect them from engine vibrations. We often used to use these as part of our ISIS engine management systems in engine control rooms: hot, steamy, smelling of saltwater and diesel fuel.

    The Vectras lasted just fine. I think any other quality computer would, too. The biggest killer is the vibrations; the heat, humidity and salt are no worse than if you lived in, say, Tampa, with no air conditioning.

    Equipment specifically built for a marine environment is always very tough, but that's the same for almost anything sold to industry instead of consumers. Industry more often wants quality; consumers claim they want quality and then run out and buy Samsung TV sets.

    Here's a radar system with a 68000-based computer doing the video processing. Here's a Great Lakes bulker, pretty small potatoes in the marine world, yet it still has a diesel engine approximately four stories tall.

    --
    Fire and Meat. Yummy.
    1. Re:Former Litton Marine Systems Employee speaks. by Malto · · Score: 3, Informative

      I don't know about just any type of computer. You'd think that things are fairly resistant to salt water and what not, but then once you're out over the salt water for a while it gets ugly. I've worked on a drilling platform in the Gulf of Mexico and things just don't stay intact for very long. Up on the rig floor it didn't take very much time at all to ruin a good set of tools just from the salt water eating them up. Keep in mind that the floor of the platform is roughly 75-100 feet off of the water and this guy will be on the water. You'd need a bit more than just a good case that keeps water out and doesn't rust to give the computer a life of more than 1 month.

    2. Re:Former Litton Marine Systems Employee speaks. by markmoss · · Score: 3, Informative

      A sail boat is quite a different environment from a power-driven ship. Jack Ganssle is an engineer and programmer with a serious sailing hobby, and he tells all sorts of stories of saiboat autopilots failing due to saltwater corrosion. I remember but cannot fine one article concerning long a single-handed race, where he had several spare autopilots and all of them failed. Since he was alone, the autopilot was critical. He kept repairing them, but his big question was, how would anyone who wasn't an electronic engineer or tech cope?

      And these things are built for saltwater, unlike off-the-shelf computers. OTOH, the autopilot would be on deck next to the tiller, so exposed to saltwater spray pretty much 24x7. The cabin would be a little more protected - there might be condensation dripping from the ceiling, but it shouldn't be salty... Still, if it's mission critical (like how you get your weather reports), it's going to be hard keeping that computer going.

  16. GoBook MAX laptop created for harsh environments.. by xTK-421x · · Score: 5, Informative

    Ripped from the specs:

    "The GoBook MAX exceeds military specs for drop, water resistance, dust and vibration. The GoBook MAX thrives in the most severe environments imaginable. Freezing cold. Searing heat. Pouring rain. Intrinsically safe,(Class 1, Division 2, Group D) the GoBook MAX enables operators to safely work in HazMat environments; on flightlines, near hazardous chemicals or explosive materials. With Itronix' innovative CRMA(TM) wireless communications, radios can be swapped or upgraded within each unit. Backed by a limited lifetime warranty and comprehensive services package, the Itronix GoBook MAX sets a new standard for ultra-rugged, wireless computing."

    Specs
    Website
    MaximumPC review

    --
    "TK-421, why aren't you at your post?"
  17. And I was such a high seas pirate! With computer! by A+nonymous+Coward · · Score: 4, Interesting

    My time in Uncle Sam's canoe club was as a keypunch operator / computer operator on USS Midway, CV-41. The computer was a tape system (no disks) with card input. The tape drive had rubber seals around the doors and various parts, and (rumour had it) could operate under water. Now, since we were one deck under the flight deck, I always figured I didn't want to be around when that was necessary.

    After the evacuation of Saigon (April 1975), Radio Hanoi called us pirates for not returning all the planes and helicopters flown out of country by the escapees. Our captain promptly broke out the Jolly Riger.

    So I am a real high seas pirate, by no less an authority than Radio Hanoi, and we had a computer built to operate under water!

  18. More problems than you might think by RobinH · · Score: 5, Informative

    Just being around salt water will cause excessive corrosion of exposed metal parts. I can remember a situation where the metal contacts between the daughterboards and backplane of a system were getting corroded and causing problems, and that was inside an enclosure.

    Putting a PC inside of a completely sealed enclosure is not always a good thing because you need to cool it down, and this is usually done with fans, so unless you also want to install an air conditioner in the side of the enclosure, you might want to find a ruggedized PC.

    There are some very sturdy ruggedized laptops out there which can apparently be dunked in the ocean, pulled out and keep going, but I think they might be cost prohibitive for you.

    Recently at a trade show I saw some industrial PCs that you could literally hose down with a garden hose and they would keep running. However, you're probably looking at $5000 even for a base model of one of those. Just look up "industrial PC" on the internet if you're interested.

    Perhaps your best bet is to search the internet for oceanographic research groups. These guys go out to sea with tonnes of electronic equipment for months/years at a time, and they seem to make out alright, probably on restrictive budgets. If you write a nice email to one of these people, they might be kind enough to offer you some real advice.

    --
    "I have never let my schooling interfere with my education." - Mark Twain
  19. Pick a dry spot by linuxwrangler · · Score: 5, Interesting
    What timing!

    I just returned from the Pacific Cup race from San Francisco, CA to Kaneohe, HI and was in charge of the computers. We carried two laptops primarily as backup and to use with the Iridium phone but the main computer was a Capuccino from Think Geek.

    We mounted a Tote Vision monitor on an adjustable arm at the nav station and controlled it with a wireless keyboard and wireless mouse. The Tote also includes a TV receiver so you can eliminate one other piece of equipment.

    For our use we needed more serial ports so we got a USB-serial converter box which gave us a total of one on the PC plus 4 external. For the race we collected HF weatherfax using mScan meteo software. The software controlled an ICOM PCR-1000 general coverage receiver via. the serial port and used the internal sound card to receive the weatherfax data.

    Another serial port was dedicated to the B&G tactician software to B&G instrument connection.

    The next port provided NMEA GPS input to the Nobletec navigation program and another provided general NMEA instrument data to Nobletec (the Nobletec software can display maps as well as a console with wind info, boat speed, heading, water temperature and whatever else your instruments collect).

    Finally, another port sent NMEA navigation info back from Nobletec to the onboard instruments for display to the driver (range/bearing to waypoint, cross track error, etc.)

    The whole thing worked great (we won our division!).

    The advice is somewhat obvious - keep the computer dry. We mounted the PC and Icom behind the breaker panel as electrical areas are generally pretty dry on a boat. The whole thing runs on 12v so we didn't need to run the ship's inverter. (Capuccino uses a 12v-18v adapter, Tote is 12v native. The Canon printer is 13.6v and worked great only when the batteries were fully charged).

    Heat build-up is a problem on hot days or in the tropics so we added a fan to pull air through the instrument/electrical compartments. This solved our heat-related crashes.

    Access to the computer requred twisting two screw latches so it was pretty easy but not convenient if you need to access the CD a lot. It's likely that you could find a spot near your nav table to mount the mini-PC where you could access the disk easily.

    I know many people who live and work on their boats. Most use laptops but one uses regular PCs with a huge LCD monitor. None have really had any trouble but they don't leave the computers where they are exposed to the elements. Usually a boat that is large enough to live on has some dry areas.

    As to the other question, you need industrial electronic enclosures. I don't recall which companies make them but my former roommate worked on systems that were used in food packing and they used standard enclosures designed to withstand the 180 degree 1000psi pressure wash that they used to clean the processing equipment. Google??

    --

    ~~~~~~~
    "You are not remembered for doing what is expected of you." - Atul Chitnis
  20. Mineral oil doesn't work by artemis67 · · Score: 4, Interesting

    Or I should say, it works too well. The system worked great initially, but pretty soon the oil got in between the connections of all the components that weren't soldered or printed on the mainboard, and thus rendered each of those components useless (CPU, memory, video card, and anything else in the PCI slots).

    The only way to do a mineral cooled system would be to solder everything down. Of course, then you couldn't upgrade anything. I guess that might work for a laptop (how many people actually upgrade a CPU or a video card on a laptop?), but the memory would need to be maxed out, and then you have the extra weight of all the mineral oil in there to lug around. So maybe not.

  21. Use IEC-945 by MountainLogic · · Score: 5, Informative
    There is an IEC spec number 945 for marine electronics. It is a very good one and you should follow it. Do NOT follow some land based spec as the marine environment is unique. I was lead EE for a team that designed the hardware used for navigation on many US Navy ships, supertankers and large fishing vessels and let me tell you meeting IEC 945 is tough.

    For example, there is a special RF emissions curve that you need to meet to be sure that you are not preventing your radios from hearing weak emergency calls. Also, power on ships is VERY problematic. Just what does "Ground" really mean on a ship? I saw 100 V potiental between Ground and Neutral on a US carrier. And you do not want to know what all of this does to RF shielding. While RF may be no big deal on shore, remember that you are using radar and all kinds of radio communications on board ship. One thing that kept surprising me was the levels of ESD on board. I assumed that the moist marine air and metal decks would kill any ESD, but I had to keephaving to over building ESD protection for our keyboard. The other kicker is that the ship has to be kept in electrical "balance" with the sea to keep the metal from coroding into the sea.

    Another area of the spec that surprised us was vibration. The shake and vibe spec on IEC-945 is a bear to pass. We started with a standard industrial chassis resting on shock mounts in the base of our console. We put that on the shake table and it killed the PC dead. The vibration was so bad that it caused the fingers of the backplane connectors to cut through the daughter cards. I was seeing fiber glass poking through the gold fingers when I did a post mortum. As an EE I learned that intuative answers are not good enough for the "real-world" mechanicals and that you need to hire a shake and vibe ME to make it work. (As an asside I had a friend who had his 36 ft sail boat out in the ocean and hit a standing wave that rattled his boat so hard that it shattered his ceraic head. Gotta wonder what the impulse was on that hit)

    There are also a host of other issues such as fungus that will grow inside warm enclosures and choke-off ventalation

    You should be able to buy IEC 945 PCs if that's all you need (HP used to sell some). If you really need this hardware to survive buy real IEC 945 hardware if you can live without it (and I do mean live) then go buy some laptop and assume that it is disposable. You'll pay through the nose for this level of hardware, but it will be cheaper and much quicker than doing it yourself.

    -s

  22. Conformal coat by dnoyeb · · Score: 3, Informative

    In the auto industry we have a thing called a conformal coating. Once the component is assembled its dipped in a kind of goo. That coats its components and protects it. However, this renders the components non-changeable so all-in-one boards would fair much better. Plus I doubt these heat factories would like the coating that much either.

  23. Fool With a Broken Laptop by virg_mattes · · Score: 5, Insightful

    If you think any laptop will handle this, remember that he's going to be on the water 24/7, including rainstorms. If you think your laptop can handle that well, take it into your bathroom, open it and fire it up, then take a nice, long, hot shower. Repeat this every day. If your machine takes more than four days of this without getting condensation behind the screen and developing crudly goo on all of the internals, let us know what brand it is.

    Virg

  24. Military standard by zoombat · · Score: 3, Informative
    I know you're really not trying to go to the moon or underwater or spend a million bucks or anything, but there's a military spec called "Environmental Engineering Considerations and Laboratory Tests" (they block deep linking; search for Document ID "MIL-STD-810"). It's a guide for creating ruggedized equipment, but doesn't really impose any specific design requirments. (It's 539 pages LONG.)

    Also, google produces many results for "rugged(ized) computers" if you want to buy something particularly hardcore straight out of the box.

  25. Water cooled by Saltwater = Bad Idea by scotpurl · · Score: 4, Informative

    Barnacles

    If you've never seen them, they're little critters that attach to everything, and grow, with very hard shells. All oceangoing ships have to be dry-docked every so often and have the barnacles (and other ocean critters) sandblasted, ground, dissolved, and photo-flashed off the hull. This is done to improve speed and fuel efficiency. If you get into the 3rd world, sometimes you can see boats that have a good foot of ocean critter crust attached to the hull.

    Now imagine your PC water cooling hose becoming slowly clogged with critters. Plus you'd likely suction up something else, like kelp or seaweed.

    If you just want to embed a metal plate in the hull, and weld a heat transfer unit to it on the inside of the boat, that'd work nicely. A closed-loop water cooler. That'd allow you to use other fluids, like adding some glycol, so that the thing didn't freeze up, expand, and break, if you didn't use the computer some icy day.

  26. Shipboard power (electricity) by TFloore · · Score: 3, Interesting

    Check carefully into the power supply for on-ship electronics. One of the interesting things with computers on US Navy ships is the power supplies they have. Navy ships do things slightly differently for supplying electricity.

    The guarantee for shipbaord power is very different from your standard land-based poewr company. Shipboard power is (or at least was 15 years ago) guaranteed as "the difference between these 2 wires is 120Volts, at 60Hz". Note that carefully. No reference to what the actual voltage levels will be, just the voltage difference between the 2 wires.

    Most computer power supplies assume "the difference between these 2 wires is 120Volts (actually 116volts, I think) AND the actual voltage levels will be approximately 0volts and 120volts".

    The Navy burned out a lot of computer power supplies before some bright boy realized this. Having voltage levels of -80volts and +40volts did bad things.

    There's a reason MILSPEC costs as much as it does.

    Of course, if you're looking to power it off a 12VDC line, this isn't really a concern, is it?

    --
    This is my sig. There are many like it but this one is... Oops. Frank, I've got your sig again! Where's mine?
  27. Article on this topic by cindy · · Score: 4, Informative

    The current (july/august 2002) issue of Latitudes & Attitudes magazine has an in-depth article (sorry, no direct link) on selecting desktop computers for use on boats. The author makes a pretty good case for using a desktop system instead of a laptop (easier to upgrade, easier to service, less expensive, etc.). His choice was a Shuttle SV 25 with a big LCD monitor for watching DVDs and a good sound card for listening to MP3s. This guy is cruising (as opposed to living at a dock) so power consumption and the availability of parts and service overseas were factors in his choices. The article is very detailed with lots of suggestions and well worth checking out if you are planing on installing a computer on a boat.

    This issue also contains the news that you no longer need to go to all the way Caracas for LASIK surgery in Venezuela. I know I feel better knowing that!

  28. Obligatory 16 year old bouy humor ... by techstar25 · · Score: 3, Funny

    "I would go for one of those nipple things ..."

    Actually, if you are going to be on a boat for a long period of time you might want to bring a pair of those nipple things.

  29. I did it for the US Navy by T.E.D. · · Score: 3, Interesting

    I worked on the software for one of the first onboard PC systems in the US navy (and no, not the crappy CAE NT system that BSOD-ed and required the ship to be towed). There's a blurb about the overall project at http://198.65.138.161/military/systems/ship/ddg-51 -flt2a.htm , but it doesn't mention my stuff (and does mention that they will eventually be using the CAE system mentioned above. They call it "smart ship". :-)

    In general, the requirements for these systems are unreal. Among other things, they have to be able to handle 100G's of shock and vibration (I'm not a Mechanical Engineer, but that sounds damn extreme to me). This pretty much means no moving parts, so hard drives have to be solid-state. We went with a solid-state PCMCIA card that looks like a hard-drive to the system for our boot drive. A trackball was used instead of a mouse for the control device, the keyboard was built into the cabinet, and the whole cabinet was fitted huge shock absorbers under it and inside it.

    One GUI vendor was disqualified on the sole basis that they required a dongle which would have needed all sorts of extra bracing to keep it from snapping off. That's about the best example I've ever seen of copy-protection costing someone sales.

  30. Re:Okay I'm sorry ... BUT by billn · · Score: 3, Interesting

    See, what they need is a nice digital projecter. Leave the computer inside, but output the screen contents across the sail for easy viewing.

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    - billn
  31. I live in Houston...humid and hot... by wynlyndd · · Score: 3, Funny

    Normal computers work for me...

    --
    "Dogs and cats, living together...it's mass hysteria!"
  32. Re:In the factory... (one more try) by Stephen+Samuel · · Score: 5, Informative
    http://www.industrial-computer-enclosure.co.uk/wat erproof_computer/waterproof_computer.htm Hopefully that URL won't get broken...

    In any case, the stupid box has an internal heater -- Like anybody out there is going to need a heater for a P3. A couple of P4s can make a pretty good (but damned expensive) space heater!

    More seriously, though.. these boxes are made for food processing (inc. freezer buildings) environments -- although there aren't many computer components that would mind being kept at -35c (disk drives come to mind as possible exceptions).

    For a marine envirnemt, Possibly more valuable would be a closed-loop cooling system (like is often used by over-clockers.
    Off the top of my head, you might try and hunt down a marine refrigerator.. Drill holes for the cables, then grout around them with silicon.
    An external (scsi?) CD/DVD drive in it's own enclosure (smaller, easer to get to , not as likely to need cooling).
    An LCD display is probably the best idea (smaller, cooler, less power).

    As for power, you can use 24/12V->110V power inverters by people like StatPower (or whoever bought them). They range from 50W units that are good for laptops to gargantuan (KiloWatt range) monsters. A 250W unit is about the size of a 5" drive, but gets reasonably hot by itself.
    Companies do make units specifically for marine operations.

    That having been said, though... You may want to look for power supplies specifically for marine operations.. You're already starting with 12 or 24VDC. No real need to punch up to 110AC and then back down again.. All you really need are some medium-amperage voltage regulators (especially if you're starting at 24V). A two-stage regulator (24V->16V, 16V->12/5V) should give you the cleanest power you could ask for.and FAR simpler too. You could probably arrange to have the PS cooled by a sea-water sluice. (less heat to worry about inside the CPU enclosure). There are probably all sorts of people capable of building on for you (if absolutely necessary).

    Gotta run now.. off to the beach :-)

    --
    Free Software: Like love, it grows best when given away.
  33. A LOT depends on the size of the vessel... by davebooth · · Score: 3, Interesting

    Lots of suggestions about just keeping a computer somewhere dry but in a small sailboat, bare minimum for one person to live aboard for an extended period? Good luck finding anywhere that doesnt accumulate salt deposits over time if its open to the atmosphere. Problem is, once those deposits are there (even if they are not visible to the eye) that surface will never be truly dry, even on the hottest day. Nowhere is safe. The best deckheads develop persistent small leaks over time, particularly near the gunwales or worse still by the foot of a deck-stepped mast. Most "watertight" hatches on sailboats only qualify for that name on the grounds that if you get a wave over the deck most of it will drain off rather than go through. Assuming the craft goes anywhere other than the occasional brief trip around the harbour the phrase "dry stowage" on a boat this size is at best a relative term.

    Now look at larger vessels. In general if they are large enough to have a genuine superstructure (ie you can be "indoors" with your feet no lower then deck level) then you stand a chance of keeping dry stowage dry and might get away with trying to protect a regular machine.

    The harder you sail the worse it is of course. The engineers that have posted are absolutely right about the impacts and vibes and again the larger vessels have it easier (If your deckhead doesnt leak now, dont worry. After a couple of seasons pounding like this, it will.) At one point I saw the same piece of (genuine marine-quality) electronics installed on 2 craft. One was the 24-footer that my dad & I sailed all over the Irish Sea, the other was 42-foot motor-sailer that a friend had. My dad & I raced in ours, our friend took leisurely coastal cruises, so long as the weather forecast was perfect. Guess which piece of electronics died first?

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    I had a .sig once. It got boring.