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Outdoor Computer Cases?
danci asks: "I'm building a wireless network in a local community using Wavelan/IEEE cards. I'd like to avoid purchasing Wavelan access point so I'll try to use Linux instead. So I'd like to build some rather small but robust machines that should be able to survive summer, winter, snow, rain and most other weather conditions while being mounted on the antenna mast (or at least as near as possible - cable length heavily decreases range).
So I guess what I wanna know is whether there are any weather proof, computer (PC) cases available out there. Or some other, low-cost solution (don't want to build a house around all that)." This would be too cool. Just imagine, a series of computers mounted to telephone poles with wireless network cards...
Look at some of the sailing/cruising magazines (some have web sites). There are several makers of hermetically sealed computers to keep out the salt-filled air - which is deadly. I'm not sure they are waterproof however ....
Hmm. Idont know. An outdoor case while seemigly attractive... doesent seem incredibly feaible. You would need a compleatly sealed case and power supply and all that fun stuff. But even beyond that, wireless technologies are still painfully slow compared to what most land lines offer. I suppose you could encase the entire thing in a plastic box... and run some conduit down the pole for power cabling... but you probably thought of that already. You could ask wavelan too, although they probably wouldn't tell you. In any case, i personally think its kind of like shooting yourself in the foot. I also dont have a tremendous knowledge about wireless networking. If you can seal the case, and make it small enough to fit on the pole though, by all means let linux rule and the peons drool.-n-rs-
I'm thinking something along the lines of this:
http://www.tisch-env.com/pq200.html
People have already a put a lot of effort into building weather-proof, battery- and solar-powered cases which can hang on telephone poles for applications such as environmental monitoring. They hang them along highways (some of them have a hook on top to hang from a telephone pole and come with a big forked stick to facilitate getting them down from the pole), then you come back in a month to check what sort of pollution is being produced. Don't reinvent the wheel here, talk to one of those companies and see about getting some cases, maybe with power supplies included but without the environmental equipment.
--
Michael Sims-michael at slashdot.org
Just imagine, a series of computers mounted to telephone poles with wireless network cards...
:)
And a nice pick for any passing burglar
It would be way-cool, but then why not use the telephone wires...?
just wrap the things in plastic - put a plastic bag and wrapping to fully enclose the case and get waterproof cables (should be available in most outdoor stores). Also try and use a chip that runs cool..something like a cyrix MII with power saving modes and you should be ok. Getting a ruggedised laptop is another way or a mil spec machine.
Take a look at Dolch. They make some pretty tough machines (some are even bulletproof)
www.dolch.com
You're asking for a lot... Not only do you want to bring a PC outside, you want to mount it on an antenna mast? It's a lightning magnet. Even without lightning strikes, you're dealing with a lot of static electricity. If that doesn't kill your PC, chances are the variances in temperature and humidity would.
Having said that, it still sounds cool.
I have to wonder though, if your only concern is cable length, why don't you just install a signal repeater or cable driver of some kind outside and bring the PC indoors somewhere?
A cable driver is a lot less expensive than a PC... =)
How do you protect a case from the elements while still providing enough air circulation to keep the processors happy?
That would be bad if you spent all the money on sealing a case only to have the processor burn up on you in the summer heat.
Outdoor case? Near antenna masts? Ok, what about lightning?
By sealing it up, you're not letting much air pass through, and the thing will eventually heat up (depending on how big the case is). Especially if it's outside and you don't live in Alaska. I don't think that succeeding in this venture of yours will be cheap. I can't imagine that the boat equipment that someone mentioned before runs so fast that it generates a lot of heat... for this to be cheap/feasible you will probably be stuck with sealing up a slow computer.
You'll probably want to elimnate all mechanical components (i.e. hard-disks) unles you can somehow limit the temperature in the enclosure.
World's Toughest Computer Case by Pelican This case is unbelievable -- watertight, airtight, crushproof, dustproof, shock resistant, and attractive enough to use as an everyday attache. Includes a lid organizer that, like a regular briefcase, holds papers, pens, cell phone, etc. There's... www.landfallnav.com Might not exactly be what you ae looking for.
I looked at these with the idea of setting one up by my pool so as to have music, but the cost for non-mass-market stuff like this tends to be prohibitive. It's also not clear that you can get a PC/104 format wireless ethernet board.
Grant Taylor
The two primary resources I'd recommend looking into are:
- Embedded Computing
- ARRL
- RAC
...those are just some starting points. Embedded computing applications have the hardware designed for rugged environments, and amateur radio is a handy technical resource for do-it-yourself electronics. Remote relay stations are the norm, not to mention other extremes.
Search engines are your friends, particularly Google.
de VE3SLG
--The more you know, the less you know.
Here's an idea - use one of the embedded versions of Linux to run an ultra-small server - (/. has run several articles on this including one about the Worlds Smallest Server) - and use a standard industrial box to enclose the whole thing. Digi-Key or Resource Electronics or just about anybody has those.
Since we're talking about a wireless network you're probably not going to get off cheap but you can almost certainly manage to produce something stable and with a long up-time that's affordable.
"Bah!" - Dogbert
No desktop type components are going to handle outdoor temperatures in any but the most mild climates (read, SEATTLE). Working with pole-mounted equipment design myself, I was surprised to find that even military-grade components may not be up to the task.
You'll at least need mil-spec components for the harsh environment you're describing.
Check out the embedded computing folks... They've been putting together tiny PCs for years. Check out stuff in the PC104 form factor... should be fairly easy to find a system and ruggedized case, because they're used a lot in avionics, industrial control, and a bazillion other "non-tradional" roles.
Problems you'll run into are weather fluctuations (hot in the summer, cold in the winter), humidity/condensate, direct sunlight does nasty things to some plastics, birds, squirrels (and other rodents) like to chew on cables, the list goes on and on.
And just a thought to keep in mind as you work on this... Lightning strikes really, really suck. Especially if what gets hit is hooked to your home network with a cable. And even more so if it's plugged into the same electrical circuit as your other household electronics.
You really should look into going to some Military Surplus sales (that is if you are in the US). When I was in the Military we had some old field computers called YUK's. Which is an acronym for something or the other. They were just 386 and 486 at the time but damn were they sturdy. If you could get your hands on one of them you could try to replace the mother board and CPU with a faster one and go from there. They are very distinctive computeres, they are all green and come in cases about 3 feet square. The case opens up and the computer sits inside with about a foot of padding on all sides.
My point: GHz RF has high losses in cables, but typical data rates have much more managable losses. If you can split the RF sections from the rest of the system, you can still put the electronics in a temperature-controlled environment while keeping the antenna cable short. (This assumes that the RF section will function under temperature extremes, which it may not. Test things in an environment chamber before you rely on them.)
I'm not familiar with Wavelan cards, but I'm going to make a guess here that they have both the digital and the RF sections on a single internal bus card and you don't have the option of splitting the system. In this case I would examine better transmission lines. One old technology I'm aware of is Goubeau line (I think that spelling is correct, Georg Goubeau is listed as being on the faculty at the University of Jena in Germany, specializing in the generation and propagation of EM waves). Goubeau line uses a pair of "launchers" to take a signal propagating on a coaxial cable and allow it to travel in the neighborhood of a bare wire; this nearly eliminates dielectric losses. While you'd need coax for any runs indoors, you could use Goubeau line to go from the outside wall wall to the top of your mast. I'd suggest using a flexible standoff/tensioner on the mast to keep the wire taut, and avoid the use of spacers. If you have a tower, I'd try running the line right up the middle.
Niggling issues like dealing with icing always rear their ugly heads. You may wish to design your antenna so that it is always at DC ground and have a big honking transformer to throw some low-voltage AC up and down your wire. This would let you melt ice and snow off it. If the Wavelan card provides signal-quality reporting you could even have your computer operate the heater as needed.
--
Time is Nature's way of keeping everything from happening at once... the bitch.
You will be better off just purchasing access points because they are designed for one purpose and will be more reliable in the long run. You have to look at cost to maintainence ratios, and a standard PC just won't do any justice. I would also look at the stats on the access point vs card, the access point may have better sensitivity and higher erp. -- Tom Wojciaczyk
First, standard computer board will not tolerated the temperature difference and all the static charge caused by environmental factors. You need an industrial strenght board to sustain outside conditions.
Second, the best 'cheap' solution would be to use a laptop computer put in a multi-layer box (multiple layer will give you better insulation). You have to find a way to let the air flow at a good rate while keeping dust, water, snow, etc outside.
Why the latop is a good 'cheap' solution, they are made to sustain high temperature change (at least when they are off), they can systain a certain amount of humidity and they are designed to consume less power and release less heat.
But cable length is only an issue with cable,no Fiber. Like one of the other posters said, dont reinvent the wheel if your distances are short,say less than a mile, why not run fiber optic. If not why look to the design of Phone switches. their water proof and similer in design to what you are looking for
Why stick a computer on the mast? BreezeCom makes radio-to-ethernet boxes you can hang on the mast. Then it's just a matter of pulling 10bT to the computer up to 200m away.
I've used these things before and they work great. I bridged the ethernet between two buildings 4miles apart at 1Mb/s -- of course there was a long range directional antenna at both ends.
but Breezecom has some products you might want to look at. I've never used these specific ones, but I love Breecom's stuff. You DID say low cost, which this not, but some things to do have to pay for, and having a PC out in the elements isnt going to be easy. Check out http://www.breezecom.com/Products/Antennas/ant_acc ess_overview.htm and look at the ODB1 box and the PI-CAT5. The PI-CAT5 actually runs the 5 volts it needs to run the access point over the cat 5 as well as the data. This makes the distance you can run the cables much much longer.
People are shooting in all directions here, so...
Wouldn't it be cheaper to mount only the net card to the post, in a nice case, and use a long flat cable connected to an indoors machine? Would noise still be a problem?
Finding all weather sealed computer cases are the least of your concerns. They are fairly easy to find, especially if you decide to use a SBC instead of a traditional AT or ATX motherboard. (The slot covers are very difficult to seal on AT/ATX). Do a web search on SBC to find a plethora of single board computer manufacturers. You will probably want to get something in a PC/104+ form factor instead of a backplane based form factor. Look into the D38999 series of mil-spec connectors for bringing connections out of the box. http://www.amphenol-aerospace.com/DEFAULT.HTM Don't forget to chose your components wisely. Get industrial temperature range (-40 to 80C) components where possible, and especially if you intend to use a traditional hard drive. A flash drive is better if you can afford it. Spinning up a mechanical drive when it is too cold can destroy it. Finally, put some thought into heat dissapation. For outdoor applications it is best to have a sealed box, which means no cooling fans. If you can, choose a low power consumption motherboard. (say a recent 486 class machine.) By all means, get a case that has large cooling fins on it, as that is the ONLY way that you'll ever get heat out of the box. Good luck.
duct tape. Lotsa duct tape.
Finding all weather sealed computer cases are the least of your concerns. They are fairly easy to find, especially if you decide to use a SBC instead of a traditional AT or ATX motherboard. (The slot covers are very difficult to seal on AT/ATX). Do a web search on SBC to find a plethora of single board computer manufacturers. You will probably want to get something in a PC/104+ form factor instead of a backplane based form factor.
Look into the D38999 series of mil-spec connectors for bringing connections out of the box.
http://www.amphenol-aerospace.com/DEFAULT.HTM
Don't forget to chose your components wisely. Get industrial temperature range (-40 to 80C) components where possible, and especially if you intend to use a traditional hard drive. A flash drive is better if you can afford it. Spinning up a mechanical drive when it is too cold can destroy it.
Finally, put some thought into heat dissapation. For outdoor applications it is best to have a sealed box, which means no cooling fans. If you can, choose a low power consumption motherboard. (say a recent 486 class machine.) By all means, get a case that has large cooling fins on it, as that is the ONLY way that you'll ever get heat out of the box.
Good luck.
Why reinvent the wheel? Apple has the easy to use Airport station which delivers 11Mbs and supports like 10 simultaneous connections. Just wrap some sandwich baggies aroound those suckers and string them around your community like Christamas lights. What could be easier? Although I don't know if there is any LinuxPPC support for that technology yet?
how the hell do you get the Wavelan to work under RedHat 6.1???
I have read through some extremely thorough websites devoted to Wavelan and Linux integration, but the process is considerably less fun (for a newbie at least) than, say, learning assembly language or sticking a needle in your eye.
First I have to get PCMCIA card services working through an ISA adapter, then install drivers and recompile my kernel! Are you kidding me! Redhat support offers no help on getting card services working and neither my O'Reilly Running Linux or Red Hat Unleased book has useful info.
This sucks.
I did get Samba up and running but a solid wireless network is my holy grail. I guess it is time to reinstall Win98 so I can use my cool toys.
*sigh*
Linux is great but has a long way to go.
Just venting here.
Environmental Specs:
...additional info here...there are also different units available...
Operating Temperature: 0 to 50 degrees C (32 to 122 deg. F)
Non-operating Temperature: 0 to 60 degrees C (32 to 140 deg. F)
Shipping Temperature: -40 to 60 degrees C (-40 to 140 deg. F)
Relative Humidity: 5 to 95% non-condensing
Wet Bulb: 29.4 degrees C (85 deg. F)
Altitude (operating): 0 to 7000 feet (0 to 2134 meters)
(non-operating): 0 to 15000 feet (0 to 4575 meters)
Electrical - 100-125VAC and 200-245VAC switchable
BTU Output (as-shipped): 200 BTU/hour
(maximum config.): 1417 BTU/hour)
Shock: 30G, 3ms duration
Vibration: 0.67G RMS random from 5Hz to 500Hz
Particulate Protection: Dust and dripping water resistant -
We used to use a similar types of machines as data collection units for slot machines. The PC's ran 24/7, year in and year out, in poorly ventilated cabinets in an incredibly dusty and dirty area--no moisture to deal with though... Very reliable. The question is will the machine generate enough BTU's (in the spec) to keep it warm during the winter...and will it stay cool enough during the summer.
Get an external electrical box. You know, the kind you'd hang on the outside of your house. They are waterproof and have all the cable ins and outs that you would ever need. Since they are sold in high-volume, they are less expensive than something built to milspec or specifically designed for computers.
Of course, the electrical boxes probably won't hold a generic PC without a bit of modification. Since the box will be headless and without floppy drives, keyboard, etc., you're probably better off just mounting the motherboard in the unit on its own.
That said, your greatest concern is going to be lightening, not water. If you wire the boxes with copper, you're making it an easy run from the mast to the wiring closet. For external applications, you *MUST* use fiber as it does not conduct electricity. (This, of couse, assumes that you don't want to fry your networking hardware. If you're okay with that, copper works great and is less expensive.)
InitZero
These guys build PPC supercomputers. They make some pretty sweet machines. These ones are especially interesting.
Sky Rugged Computers
You may want ot just give them a call and see what they do?
Anyways, sweet machines.....
Who is the master of foxhounds, and who says the hunt has begun? -Pink Floyd
I'm not familiar with the brand you are using, so I may be wrong, but the thing I believe you are missing is that the Access Point is usually a key part of the system in a wireless network. All the other NIC's talk to it, not to each other, so using nothing but NIC's probably will not work. Again, I could be wrong...
I think I can help you.
I'm currently working on an outdoor pc system designed to basically work in man holes (15 feet fully submersible for prolonged periods, dust/water proof). What you need (and this is only one solution, but it is cheap) is a single board computer, power supply, NEMA 4 rated enclosure, and applicable glands to bring the wires out. Basically you mount everything inside your box (generally made from fiberglass, aluminum or some type of plastic), install the glands (watertight cable feed throughs), and mount this baby.
JumpTec has some of the systems you could use, and more importantly has an IDE flash disk that makes all this easy to do without a hard disk. Also Win Systems is a pretty popular place to get PC/104 embedded systems.
As for the case, Hoffman has all the enclosures you could ever need (unless you're working in man holes).
Some people have recomended Dolche, but I'd avoid them as they are way expensive. More useful for interactive systems.
good luck
- Dan
This can easily be done in my opinion. Build the case from plexy glass or other plastic materials....make sure the power supply is inside along with some copper tubing for your cooling system as you are going to need to liquid cool if you aren't going to have air flow. Next, you need to bring the cooling tubes out of the case and build a radiator with some fans blowing across it....this part doesn't have to be very protected from the elements....then paint the thing with liquid rubber of sorts to seal it. Of course, an easier solution would be to go to a company like Fibertron....they sell several outdoor cabinets used for fiber optics equipment which are sealed from the elements. Another option would be get a tube that the computer can fit in (would have to be rather big, y/n? hehe), cap the top and mount the board at the top...run all cables out the bottom and give a few feet of extra space at the bottom...chances that the elements easily find their way up that is much less and its a very inexpensive route. -Dan Guisinger
www.atacomm.com - The Leader in VoIP Product Distributi
Parvus has several for the PC/104 size, as does Tri-M. Digital has some for their products.
There are plenty of generic NEMA enclosures available, up to walk-in size.
Remember you may need a heater or cooler. There are standalone devices, although I also have seen one PC/104 card with thermostats.
I've never tried putting it in direct rain, but we used to install computers into Sawmills and we would seal them in big tupperware containers...
OK, if you count the time to build the enclosure, you are probably not saving any money unless you are doing LOTS of em.
Maybe you need to think of something other than an "enclosure". What you want is a box that keeps the elements off your computer. Something like a very small shed with a pitched roof.
I would suggest a small dog house would be about the right size, and relatively cheap too. There are some very cheap plastic ones on the market but they'd be harder to modify to make secure. Something like this might be good, and fairly attractive. Just get a piece of plywood and screw it down over the door. The main problem is that these are rather large, although this offers room for a UPS and a circuit breaker box.
Of course, if you are planning on putting these on roofts or utility poles, this might be a little big and kind of ugly. Perhaps a large bird house. Take a martin house, plug up all the holes, and use a sawzall to cut out the internal dividers. If you can scavenge used laptops or use something like a netwinder you can get down to a regular sized birdhouse. These would have the advantage of not being an eyesore. I would take some silicone caulk to the joints, however.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
I don't know about weatherproof cases, however you did mention that you were not interested in using the Wavelan Access point. I have heard that the Apple Airport is compatible with 802.11 cards that use 2.4 GHz DSSS such as the Wavelan card. The Appple airport only costs $300 and includes a built in modem. I have received the Airport and I have ordered the Wavelan cards and am waiting for them to come in to test it out. The Airport does not allow HTTP configuration such as other access points and is only configurable by an Apple Computer AFAIK, however, the default configuration should be to assign IP addresses via DHCP so no configuration should be required as long as you have your network setup to use DHCP.
Anyway the Wavelan cards should be in soon. Email me with your address and I'll let you know the status of my tests with the Wavlan cards.
----------------
The best part is if you went with the birdhouse idea, you could call your network "martin.net".
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
I would start by visiting my local planning office to see what sort of weather you can expect in your area. How much rain, snow, how hot, how cold and how long for each extreme.
Then I would go to a building store and see what materials are there. For a computer case size object, its really cheap. In fact I would ask one of the guys there, since they would have a good idea of the weather extremes.
Next I would worry about fan exhausts, power supply, lighting and animals making new homes.
The surprise isn't how often we make bad choices; the surprise is how seldom they defeat us.
You might have to go with the "little house" concept: put an otherwise normal PC inside an outdoor enclosure made for that purpose. I'm thinking of the kind that they use for cellular equipment. But that ain't going to be cheap.
-B
Ash and Hickory, straight-grained and true, make excellent bludgeons, dandy for the cudgeling of vegetarians.
While saving a few bucks is admirable, the simple truth is that the wavelan access points were already designed to solve all of these problems and more.
If you're doing something that's non-profit (or otherwise capable of generating good PR for Lucent), give them a call and see if you can get a discount.
Otherwise, you're going to end up spending more money in the long-term on maintainence and replacement (like someone said, PCs on a phone pole would be a tempting theft target) that you would on the more expensive equipment.
Forward, retransmit, or republish anything I say here. Just don't misquote me.
Putting a computer on the mast is not a great idea. Although it can be done, it costs quite a bit for a reliable solution.
Depending on the frequency that the wavelan cards use, you can use something the microwave industry has used for decades: Waveguide. Basically a small duct with a transducer on one end that passes the signal through the waveguide on a shielded path. The waveguide is usually sized to the frequency of the transducer. Check some of the microwave ham radio pages out there. Waveguide is usually used in the 10ghz+ spectrum.
Another approach is to use a mast mounted amplifier and pre-amplifier and use a short run of 50 ohm hardline. This is what a lot of ham radio users use for high performance antenna arrays in the uhf and microwave spectrum. Basically, you keep your computer in your home, and run a length of hardline to the mast mounted amp/preamp. The signal losses incurred by the cable are overrun by the mast mounted goodies. By doing this, you can mount your antenna directly to the amp/preamp and have no loss.
Hope this helps!!runlevel0 has been reached...
We do a lot of utility work... in the sort of places no one really wants to think about (under New York City) We don't use traditional PCs, but we do use traditional pc parts (or at least traditional boards, usually with a few specailty boards. You could probably mount traditional pc parts (including the power supply) in one of the industrial cases we use - with the understanding of a couple of things... you can't run a hot processor, you have to have massive heat sinks and it takes a lot of testing and time to do it right... Think "low-end Linux box" not "quake machine."
The cases (er cabinets) we buy are pretty darn rugged (i.e. waterproof, very heat resistant, pretty resistant to shock, etc).
Now keep in mind, all external openings (for cords and etc) need to be tapped and all internal components need to be mounted in some way.
Well here's a plug for the people we buy from:
Contact information
Stahlin Fiberglass (a Division of ROBROY Industries)
Belding Division
Belding, Michigan 48809
Phone (616)794-0700
However, that's just for a PC... I hadn't even considered a monitor. If you're expecting to put in a monitor and stuff like that... it gets a lot more expensive and difficult... now what you're talking is purchasing industrial grade PCs...
Now you might be talking purchasing something from Xycom Automation. But, most of these are also flat/touchscreens ($$cha-ching$$) and once again come preloaded with DOS/95/NT. I don't know about Linux drivers for those... However if you look around enough you will find a lot of machinery does run with some form of *NIX (to avoid the reliability problems of MS)
Well, that's about the best I can do for you...
You say you want a revolution?
It would be particularly cool if you didn't seal up all of the holes, and let some birds share the house with your computer. I'm sure some feathered family would appreciate a bird house with central heating.
/peter
We use the Super Duty laptop cases sold by cases-cases to lug around our laptops in a marine environment. They definately hold up to abuse, and are comletely air/water tight.
This would be more of a "you like, uhh, put your PC into this box thing" kind of a solution, and it will probably be a little bulky. You would still have to look at temperature, and lightning problems (plastic case tho, so it might be ok).
The idea of using marine systems is fine - but you might do better by checking the yellow pages (digital or tree-based) for companies that manufacture or sell equipment for food processing facilities. USDA-FSIS requires all equipment in the main processing areas in, for example, meat processinng plants to be completely washable, often using hot caustic solutions.
Four years ago I worked for a major poultry producer and one of my projects was putting in case scaling and labeling systems in the plants. Instead of the expensive PLC based systems that everyone else pitched to us, our vendor had developed PC LAN based systems that were faster, cheaper, and more flexible. The trick was to use cheap PCs inside moderately expensive stainless steel (or in some cases fiberglass) boxes. There are established standards and components for these systems (the namees of which I cannot remember this morning) and you can get a lot of the pieces off the shelf. The external connectors were MILSPEC Amphenol type, and the monitor (when we needed it) was inside the box and visible through a sealed plexiglas window. The boxes had thick rubber seals and big stainless steel clips to keep them closed. They were not too small, so the air could circulate some, and the environment these were kept in varied from 27 to 40 degrees F.
One of the neater components was the Dragon keyboard that was first developed for artillery control units - its a keyboard with a very thin sheet of flexible stainless steel over it which you press the keys through. Not something to code with all day . . .
Tupperware
I use it whenever I don't have a case handy. Only problem is ventilation on those air tight burp-seal tops.
Put the damn thing in a garbage bag and staple it to the top of a utility pole! Get some 2' wire ties, and just run the cables down the pole. Power? Ask a homeowner close by if you could run an extension cord in his/her front door. Why spend $$$$?!?
Well, I once had mice in a 3b2/400.
As far as birds are concerned, I finished a loft over my garage to use as a computer room but didn't adequately seal the ventilation holes in my soffits. I got a family of starlings nesting in my insulation. The Dad found a way into my loft one day and shitted all over my keyboards, monitors and computers. I sealed up the inside hole, and would have let them stay, but after consulting with the local audobon, I learned that they would attract insects. I waited until I didn't hear the babies any more, and sealed the hole up and destoyed the nest.
Unfortunately, the birds had had another brood and I discovered five chicks after I boarded up the hole and I had to drown them. Five starling chicks are no great loss to the world, but on the whole I'd have rather lived with the insects.
I guess this is not entirely off topic, because if you put a computer outside, you'll have to provide ventilation, and if you provide anything with a hole of 3/4 of an inch or larger that is not coverd with a well secured metal mesh, you will get bats and birds nesting. Insects shouldn't be too much of a problem if you keep a fine mesh over the holes and don't allow the wood to rot.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Farrade cage
Ok, you mentioned it, what is it, & where can I find more information?
I did a search on Google, but it didn't come up with anything.
Just from the context of the post I have an idea of what it might be, but I want to know for sure.
--Remove chicken to e-mail
Go with mil-spec gear if possible. If you can't afford it or really want to do it yourself, heres some ideas.
Get a sealed plastic case. Computer intended or not. If it isn't specifically for computers get it bigger than you need, and rig some shock absorbing pieces in. An idea I've seen is some military field computers have pieces of rubber in the 8 corners.
Cut holes that are just barely big enough to let necesary(and only necasary) cables through. Seal them up with that clearish rubbery stuff(can't remember what its called). Electrical tape might work, but I wouldn't rely on it.
Lightning is a big potential problem. Unless you have a lightning rod with a superconucting cable, lightning will kill your computer. Make sure the antenna has a ground attached, preferably above the cable connect, using the lowest resistance cable you can afford. This may cause the lightning to travel down that rather than into your computer. Still, find out the maximum jolt your computer can take, and get a fuse that blows out somewhere between 80% and 90% of that. You will still lose connectivity, but rather than having to replace the whole computer you will just have to replace the fuse.
Everyone thinks cooling would be difficult. Not really. You may want to look into a water based cooling system. They can keep your CPU extremely cold. Condensation can be a problem though, be careful about that. And don't screw up putting it together. The result of a mistake setting up a computers water cooler is obvious. Another option is setting up a big fan and ducting air in through plastic or rubber tubes, or even PVC pipes. HAve a top one that blows cool air in and a fan in the bottom that sucks hot air out. Through ducting you can keep the case cooled and airtight/watertight. The hard drive could be a problem. Bad things can happen at low temperatures trying to get a motor running. Primarily, get the drive with the greatest temperature tolerance you can afford. And among your options there, get the one with the best g-force tolerance you can find. No matter what this thing will be taking some shocks especially in a storm. Turning off all powersave options, or at least the ones that relate to the hard drive, may help keep the hard drive from getting too cold.
All in all an ambitious project... but certainly feasible.
I would suggest talking to Kryo Tech. They have some low end cooling setups that would cover the temperature problems. www.kryotech.com Then all you would have to do is place the case inside a sealed, locking box. My question is, what are you gonna do for the Keyboard, mouse and monitor? Your users need to have access to the keyboard and mouse, I suppose you can put a plexi glass window on the front of the monitor. My main concern would be vandalism and theft. If you put 1500 dollars worth of computer equipment out on the side walk, it's gonna disapear.
OK, if you're a programmer, putting a computer on a mast sounds like a good idea. (Temperature will KILL it, BTW.) To an RF engineer, it sounds like what we really need here is a low noise amplifier/power amplifier combination. The LNA will reduce the noise-polluting (i.e., increased noise figure) effect of the long antenna cable, and the power amplifier will boost the transmitted power back up the Part 15 limit. This sounds like something Wavelan or other wireless LAN outfits should put together.
www.backwoodsengineer.com
I worked with SCADA systems where we had to mount the computer within a metal cabinet with a hermetically sealed door (which was bolted down in, IIRC, 4 places).
While these puppies can't be cheap, there must be a mass-market (or close to mass) considering that the cable companies and power companies need these.
And, hey, my experiences were 20 years ago.
These cabinets would've been big enough to handle PCs, BTW, though I'd worry about heat distribution (you're not gonna want to use a P-III, Athlon, Alpha or whatnot...).
Of course, you could go into business building these puppies in such a way that the CPU heat-sinks directly to the case...
-soup (GNUrd, Speaker to Machines) "Laugh at yourself- Why should everyone else have all the fun?" -Romanchek's 6th Ru
That's because he mis-spelled it. Think Michael Faraday, as in the guy after whom the farad is named.
--
Time is Nature's way of keeping everything from happening at once... the bitch.
There is a solution already done that is exactly what you are looking for, but it may be a higher cost than you are expecting. The company where I work, Intermec, makes wireless networking products for manufacturers and warehouses primarily. We have a product known as the Universal Access Point that was designed and tested for extreme environments. These access points can now use Lucent 802.11 radios. You can check out the specs and get more information at: http://www.intermec.com
My (scuba) diving club has given up on "waterproof" electrical hardware (we're talking radios, GPSs, etc) for use on our inflatables because most of it just isn't. Instead, we now buy non-waterproof gear and keep it in sealed (big plastic clamp, nothing wimpy) transparent bags.
My point is that you can probably make it waterproof fairly simply after you've packaged it all up - you don't necessarily need the case to be environment-proof.
The "bag" idea also means it's easier to replace damaged housings; they'll get broken whatever they're made of.
--
Tim.
People keep talking about problems with heat dissipation. One possible solution to this might be to submerge the entire computer in mineral spirits. I saw a picture of a computer that was set up this way once, in order to provide cooling for overclocking (sorry, can't find the URL, but search Ars Technica for a link). Mineral spirits are nonconducting, and have been used in electrical transformers. If you put the computer in a ridged metal box, you should get okay heat transference from the box to the outside. You could even put heat sinks on the outside of the box if need be.
I don't knwo what this would do for other environmental issues like cold or moisture.
I have no idea if this would work, but I thought it might be helpful, and it shouldn't be too expensive.
Jon
All opinions expressed herein are my own, and not those of my employers, who are appalled.
I've got a NEMA enclosure with a 40 Mhz. 486, hard disk running some serial devices. It's mounted on a telephone pole and has run reliably for years. The only failure I've had was the power supply and the CMOS battery. We built a sheet metal "shade" for the enclosure but in 100 F heat the inside temperature never went above 140 and it's never failed due to cold. It is in Northern New Mexico so it gets a pretty wide range of temperatures.
As for modern equipment, a lightly loaded AMD k6-2 with a heat sink will probably do the job forever; just don't build any kernels on the damn thing during a heat wave.
You *will* need at least one conductive heater per box, they won't survive winter without them, (the heaters prevent internal condensation) :)
As for casings, RS Components sell rated-seal enclosures for (fairly) reasonable prices, but at least you get a warranty for any leaks
otc: Wouldn't you be better off using line of sight optical networking? - is that possible?
Ripping an new rectum in the fabric of spacetime.
I don't know what kind of budget you have to keep to, but yachtsoft.com has "marinized" laptops. Their Argonaut can take having water poured directly on the keyboard. They are compact and rugged, yet still have the functionality of a real computer.
I stole this sig from a more creative user.
Note: you have to be concerned about heat, since if you add a fan hole you are no longer watertight. Use low-power parts and you are probably fine. One nice aspect of keeping the inside a littel warmer is that you limit condensation inside. Use light colored boxes (or better, unpainted silver) to reflect as much sunlight as you can to limit heat in the summer. It's smart to put a 1/4 pound bag of dessicant inside too - eats up moisture that you do not want condensing out on your PC.
Note: you are going to have issues with getting space on poles. Talk to the power and phone utily first - they may donate space, but there are rules about how the box can get mounted - you have to honor the "climb space" so that repair guys can work, etc.
Note: use silicon goop around your antenna through-hole - even if you use good rubber gaskets. The gaskets never hold, and the silicon goop is good insurance. Plan on inspecting yearly and replacing the outside goop layer... it deteriorates in the sun and heat.
Best of luck! Write me if you need more info.
[Sidenote: Do teh x86 chipmakers even *try* to design CPUs that don't need heatsinks anymore?]
The case must also be sealed with some silica gel packets inside to prevent condensation from forming in cold weather.
For really cold sub zero weather, you have to worry about the oil on hard drive mechinisms becoming thick gelling up. and may need a heater inside the case.
For super hot weather 120F/50C you may be SOL unless you can keep your case shaded as metal exposed to sun can reacj 150F/160F easily.
Perhaps the best solution is to bury the case underground (with heating for sub zero weather in winter). Resistance to corrosion is now an issue. This will keep the case cooler in hot months too. (Living in the deserts of Nevada, I have to worry about temps ranging from -15F in winter to 115F in summer.) Good luck.
Watertight and cool running satisfies summer/southern conditions.
How well insulated does it need to be?
Is cooling going to be the only problem, or will there be a need for heating? ( "Forecasts are for temperature reaching a high of -3 F and lows in the -40s F for the next several days" Yes, that happens)
I suspect there are different answers for different regions. Although the idea is not to "build a house" for it, that may be the best choice in the nastiest places. I know of a radio repeater system that requires 4WD vehicles and good hike to get to...in nice weather. The answer was to build a "house" with a small furnace and a luggable tank of LP gas.. to keep things just warm enough through winter. Not warm. Warm enough. You still need to wear a good coat in there, but the electronics work.
And in the Deep South or closer to the equator I expect there'd be an equally valid yet much different solution for the problems there.
The Apple AirPort. I've been hacking on this for a few days now with my notebook running SuSE 6.2 and a WaveLAN Gold.
The AirPort is cheap ($299), encased in plastic already, is in reality just a WaveLAN IEEE card with 56K modem and 10^T ports, acts as a DHCP server and NATting bridge, and is SNMP configurable/monitorable. And it has a small footprint and comes with mounting hardware.
I'm currently working on figuring out how to reprovision one of these things using only SNMP calls, so I can code up a quick app under Linux to do the job (it currently can only be provisioned using a Mac and their provided software).
With WaveLAN Gold cards (128-bit encrypted streams, 11MBit) selling for $200 these days, it's an attractive solution.
.@.
...am I the only one that has dreamed about irc'ing from underwater? Someone needs to come out with some waterproof laptop...call it the h2oBook or something. Think of all the poor marine researchers stuck underwater for long stretches of time, cataloging fish, watching the coral grow and other such tasks. Its about time someone started to hit this market up....and hey, wouldn't you love to be online from the bottom of your pool with a webcam for all to see?
http://www.uclinux.org/simm/
It could run off rechargables, and have a really small power supply to connect to the grid (or even a small solar array would be more than enough to keep a set of rechargables topped off for a few days of cloudy operation).
Oh yeah, it runs Linux. Although it is very limited, at 8M RAM, it may be all you need. The only problem you need to solve is getting wireless to work with the board (maybe some of those unused I/O pins?).
Something that small could be totally encased in polycarbonate - that would eliminate any worry about condensation. Imagine the whole thing, solar panel on top, circuitry on the bottom, encased in a solid block of polycarbonate! Wonder what the MTBF of that puppy would be?
(guess the rechargables would have to be external, unless they come up with the NiEternity battery)..
The ATM machines are probable the best to use for this applications. Just back up truck, attach the chain and let 'er rip. Oh you can try to conact the company that makes the ATM's...
-Ellis of Geeknews.com
In the white paper on the WaveLan site they mention that Carnegie Mellon University in Pittsburgh is actually implementing a WaveLan system across their campus. I'd talk to them before you do anything. Anyone from CMU's IT department care to comment?
WaveLan white paper
Aetius
This may be off-topic, but did you guys see this!?
http://www.cutler-computer.com/xtralite.htm
Now, if we can just boot Linux on it...so much for the Visor!
D'oh! My next computer!
what about using a mips processor (like the netwinder), from what i hear they use VERY little power consumption, dont need a fan etc etc...
Just a thought
The company name is ISPW, S.A. 506 280 8860. I had purchased a internet high speed linux box (THANATOS) and some software from them for multipoint to point wireless connectivity for my network here in Orlando. I have been using it about 3 months and my internet is fast, very, very , very fast. we have some friends that have hooked up 2 miles away and are receiving approximately 600 to 800 kbps wireless, and downloading at upto 170k continuosly. We download 4meg mp3's in less than a minute wirelessly. I think for the price of one wavepoint from LUCENT and being able to hook up people upto 80 miles away (depends on antenna and amplifier) it would be cheaper then a computer on every telephone pole and easier.
if you need to compute outdoor ! ;))
;))
look this !
www.cycomm.com
its very interressting !
more big than usual laptop computer, but, interresting
Amazonas
If you want your equipment safe from environmental conditions get a NEMA enclosure. If you don't mind being a little creative you could mount an entire computer system in a NEMA enclosure or even better work with a company to customer configure one of their enclosures for you.
I have read many posts on this board about the case getting too hot, since it would be air tight. Well, I thought you geeks would have remembered those lovely geek toys called peltier cooling devices. You could line a metal case with them, paste heatsinks ontop of the mess, then seal everything up.
Buggy internal buses...they've been screwing us for months.
Duhhh!!!!
How're you gonna receive omni w/ a waveguide?????
Before I go on, address any forther questions to
lwolf@thespleenpress.org. I detest web-based
discussion boards...God created the UseNet for
a reason.
-----
Since the idea of a resident Linux box mounted to
my truck has been kicking around in the back of
my mind for several months now, I too have put
some thought into outdoor computer enclosures.
I am thinking of going completely homebrew on
this.
Here are a few suggestions In No Particular Order:
1. Look through electronic supply catalogues for
NEMA type enclosures. These are used
to enclose electrical stuff in industrial
settings where shit needs to be waterproof,
oilproof, dustproof, and shiteverythingproof.
The NEMA enclosures run in a multitude of
sizes and come in both plastic and metal
I have found Newark Electronics to have quite
a selection of these. Get their HUGE catalog...
you'll find the size you need. Try also MCM
Electronics.
2. Unfortunately, shitproof also means airproof...
which is ickybad for computers. I'd suggest
making two air ducts on your box...one on top
and the other on the bottom. The bottom is
just an inlet; it should have some sort of
chintzy filter material to keep out extraneous
dust.
Get some plumbing-type elbows for the top
duct and fashion the vent so that the air
escape points downward -- this will hopefully
keep out water. Oh yeah, on the inside of
the case, attach a fan to this duct so that
it will force hot air out.
3. Run cables in/out through the bottom. Drill
the smallest sized holes you can get away
with. Use rubber grommets in the holes.
Seal with plumbing caulk or, better yet,
automotive RTV (cuz your car is an outdoor
device after all). I would recommend the
Ultra Black or Ultra Copper RTV instead of
the standard Blue RTV, but the blue stuff
should work just fine.
4. Taking another tip from the automotive world,
pick up a tube of Di-electric ("Tune Up")
Grease while you're getting the RTV. Apply
this stuff to ALL of your electrical
connections. This stuff -- which looks just
like vaseline -- keeps moisture out of your
electrical connections and keeps your
terminals from corroding.
There is also a spray-on coating for auto/
marine electronics which dries into a thin, clear, rubbery coating to protect circuits
boards against moisture.
5. It probably wouldn't be a bad idea to pack
a mess of dessicant packets into the box.
6. Run a THICK ground wire from the box. I'd
go with 1/0 AWG. 'course, if you get a direct
lightning strike in close proximity to the
box, it's probably toast anyway. But you
should by all means construct the polite
fiction that your electronics are properly
grounded anyway. }:)
There's more, but I can't think of any off the
top of my head right now. Good luck!
/lw
Your entire case at sub-zero temperatures... 1Ghz here we come :)
Of course this doesn't work if you live in a hot country [jealously vibes]... grrr..
Check out industrial shops. They have 100% sealed cases for use down on the factory floor's and are EXTREMELY sturdy and secure. If i wasn't at school right now i would look them up for you..but back on to AP Computer Science
the routers are embedded linux systems running all off a boot e-prom and loading OS over wireless, keeping the rest in cache/ram.
The south-east where I was starting this wasn't quite ready for it, so the company is gone now and I'm in San Francisco. However if anyone is serious about doing something with wireless & linux please feel free to get in touch with me and I'll pass you onto the vendors.
btw the linux router is something you have to assemble yourself. So get your eprom burners out & figure out how to get a NFS mount via serial connection and boot kernel only! :)
------ Imagination is Greater than Knowledge (Albert Einstein) Every day is a good day, whether you like it or not (DM
Lucent has a product called WaveAccess that is specifically designed for the outdoors. WaveLAN is more internal... Wave Access
The Airport Base Station is simply an Wavelan card (Supposedly Wavelan Gold), a modem, and a 10 BaseT adapter with some microprossesor taking care of everything. I believe you can simply talk to it over TCP/IP, so it should be OS idependant. All this for a scant $300, (close to the cost of the Wavelan card)
See www.macintouch.com/airport.html for more details, and hackers reports about airport.
After reading many of these comments, it got me thinking about wireless technologies. It seems to me that using a Linux box with wireless transceivers indoors is fine, or maybe two neighbors setting up a little wireless network, but when it comes to large-scale outdoor deployment, it seems to me that it'd cost more to develop a Linux solution than it would a custom-tailored embedded solution. Anyway, wouldn't it be cool to be able to purchase DSL service from your local ISP, but instead of running the phone line into a house, run it to a little gizmo on top of the pole? This little gizmo would have a DSL router-wireless lan bridge inside, and would be a tiny little thing not worth stealing. If it was damaged by lightning, it would be cheap enough to replace. Possibly it could be powered off of the same telephone line it uses for the DSL...I don't know...I'm not an engineer, so I'm not sure if that's possible. Anyway, it's not to hard to find a pole with a step-down transformer on it, and I'm beting if you contacted the power company (you're going to have to deal with them anyway in order to get the gizmo on top of the pole) they'd be able to get a pole-mounted meter hooked up to the 120V powerlines...just like the meter on the side of your house. And your little gizmo would have a little transformer to step down to whatever voltage/amprage it needs. As far a power consumption charges, i've seen power meters equipt with little transmitters so that the person who checks your meter can get a reading without actually having to read it off the meter. (So these poor people won't have to climb the pole on a Minnesota Winter day with a windchill of -50F, for e.g.) Or, some might even have the little fax circuit to sends a fax to the billing office each month over the same phone line that that DSL service is provided on (my water meter has this.) Hey, even better: wouldn't it be nice if local ISPs got togeather and setup a metro-area wireless LAN. Then all you'd have to buy is the little wireless LAN PC Card for your laptop, and let the ISP deal with what goes on top the pole. Just some ideas...
According to users at macintouch, the Airport BaseStation IS a wavelan card, check out www.macintouch.com/airport.html
I know you can get environmental enclosures.
The only real reason for an Access Point is that it can handle multiple radio domains, so as to releive congestion if you have many remote stations in the same area. (if you simply use the pc cards to do it, it will work fine, but all share the same channel.)
My company sells exactly what you're looking for. It can be custom configured to whatever specs you want, heaters, air-conditioners, batteries, etc. Using standard rack-mountable equipment.
http://www.adspower.com/
(800) 443-4742 ask for Keith Dykes, tell him Darren sent ya!
-DF
I'm writing this from a laptop with a Ricochet wireless modem. It rocks!!! It's only 28.8 Kb, but they'll be rolling out their 128Kb service to 21 cities within nine months. Rest assured, I'll be one of the first in line for one. Sure, I'd like more speed (who wouldn't?), but nothing beats being able to go anywhere in a wired city and be connected to the net. I've been using it in hotels, airports (even on the plane at the gate!), the metro, work, cafes, and friends' houses. Oh, and it's a flat rate charge, so I'm nearly always online, no matter where I go.
If these things are going to be outside, take special note of the humidity note: non-condensing. If you get dew on your plants and grass early in the mornings, you'll probably end up with a wet motherboard.
"Dripping water" resistant doesn't mean crap. You can probably claim most any indoor AT case is "dripping water resistant."
Also be careful about the temperatures. Granted, if it's up 24/7 you *probably* won't have to worry about it getting too cold, but if the temperatures inside your computer case at home tend to climb to 100+ degF, just think what it'll get to sitting in the hot sun.
I haven't read anything about these, but it seems like they're more appropriate for indoor/climate-controlled industrial use, not for outdoor use.
The age of cheap, high-performance embedded PC's is upon us. While they are going to be slightly more expensive than an ordinary PC of the same calibre, they will handle being fielded into hostile environs well and provide almost all you need for this design on a single board. Pick one of the "lesser" embedded PCs (like a 486-DX2/66, for example) with a PC-104/PC-104 Plus expansion option. It will fit into a medium sized plastic NEMA enclosure along with the power supply and the WaveLan card. Now, you want to probably use the PCMCIA version of the WaveLan because unless you can find a small, clean version of a PC-104 to ISA adapter, you're going to have to add a PCMCIA card interface PC-104 extender card on the whole configuration. Either obtain an embedded PC with onboard 10-base-T or obtain a 10/100 ethernet PC-104 extender card for the ethernet feed back from this router. Follow all of these up with a 4-8Mb M-Systems Chip-On-Disk for holding the mini-Linux distribution of choice.
Whole system cost: ~$700-1000 per machine, depending on how cleverly you shop.
This is cheaper than trying to NEMA a stock PC (which is what you're needing and looking for!)- that would run you ~$2-4k for an average machine enclosure and machine before you're said and done.
I am not merely a "consumer" or a "taxpayer". I am a Citizen of the State of Texas
please...
It all depends how much of an offset (if any) is between the send and recieve channels. It also depends on the bandwidth of the channels. When you're talking microwave, the bandwidth is (relatively) small. Therefore, you can have both signals passing through the waveguide at the same time without interference. Radio waves don't "run into" eachother.
The other possible scenario is that both channels are multiplexed travelling on one carrier (how do you think a phone line works full duplex on 2 wires?) I can't confirm this as I don't know the specifics on this card, but it is done quite often.
You should consider doing some research next time...
You could build an air tight case using acrylic. Take the case off and just use the metal skeleton and build the acrylic case around it.
Seal the entire case with a submersible sealant (like silicone, or some pool sealant).
Only problem would be exhaust from the case, you can't seal that off. But you could run piping away from the case and hook it up to the case.
"Imagination is the only weapon in the war against reality." -Jules de Gautier
There was a german company that was on the "System 98" fair, that built such computers. These laptops came with "Intel-inside". They were shockproof, waterresistant and dustresistent.
Even in a sealed box, condensation will be a problem unless you throw in a couple of 1 lb bags of dessicant (DO NOT EAT). Swap them out with some fresh bags every 6 months or as needed. Some bags have blue/pink indicators for good/replace decisions. Use the microwave to dry out and recycle the old bags.
Use gold contacts. You can also get fully sealed contacts. Get a DigiKey catalog, look through the contactsd section, they have waterproof contacts. Place all contacts on the bottom of the box so if they do develope a leak it still won't leak into the box. Take a look at a telephone company box on a telephone pole. They aren't even water proof. They are just designed to shead water well, and if water makes it into them, they have a clear path for it to exit without it going over any circutry. As for what I'd use, I'd look at using the heavy plastic electrical boxes designed for outdoor use. Grainger has them (you should be ale to order through them as the community or as a busisness).
My concerns: Heat, Power, Size, Antenna, Software.
Things I would do:
Condensation is the problem. This happens a lot when the highs and lows are that different. Where I live (Southwestern Ontario Canada) it is fun to hear the "crispy" grass under your feet in the spring/late fall. Look at the dew on the flowers.
It is true water isn't conductive unless it is "dirty", but even the slightest impurities make it quite conductive. This is why dropping a plugged in radio into the bathtub is deadly - because your body (and the tub and radio itself, they won't be perfectly clean) introduce impurities into the water.
It'll be not so bad for some always warm environments (Arizona?), but not if you ever get rain, snow, hail, etc...
Just plug the computer into a 300 VA 1:1 transformer (NOT _auto_transformer! these can still be ground bonded!) (any decent electronics store has 1:1 transformers, NOT radio shack. about $100 to $500), and break off the ground pin. Test the case for voltage to ground when it is plugged in before you touch it or attach anything to it, just in case. If you don't and your transformer isn't right, you could be in for a 120 V shock!
Find a good weatherproof cast aluminum housing (with rubber seals). Drill two holes for a pair of BNC connectors. Install the BNCs, solder down the RG174 to the BNCs. Etch a +5 Symbol on the housing for the power connector, and ANT for the other. Connect up a suitable onmi antenna and power, seal up, and enjoy.
-=paulf
...-.-
On earth there is a little thing called lightning.
drug law enforcement is modern day witch hunting.
Why not just setup one or two nodes with more power output? I designed a 13W amplifier for the older Wavelan 915MHz cards. Those IEEE ISA cards are fuckin junk. Really, get something that puts out the full legal 1W. As much as I hate Aironet, I think they do have a 1W card. Also use the 900MHz variety. The 2.4 and 5.8 jobs don't work all that well over non line of sight paths, but I've found 800mW-1W will generally get the signal where it needs to go within reason. With ~4W and a pair of 915MHz wavelans I'm able to hit a site 13 miles away. The path it basically LOS except for some vegetation and a few small hills. Try to get some hardline or some coax used in cellular base station applications (made by Andrew, but I forget the part #). I thought about mounting a PC on a tower before, but it'd really be too much of a maintenence nightmare, especially for us, who just do this sort of thing for the hell of it. We have access to a DS-1 and 2 class C blocks so it's pretty cool. I just hope no "commercial wireless" people come in and ruin it, but I guess that's the name of the game in america... piss on everyone else for profit.
In this type of application where high availability is desired and the cost of servicing is high, the first thing you could do to reduce the risk of failure is to get rid of the disk drive in the system.
They are prone to mechanical failures, data errors induced by electromagnetic fields, data errors induced by extremes of temperature and humidity.
Disk drives are too fragile for application in a hostile environment like the top of a utility pole.
It is not clear to me what the purpose of the network described in the posting is intended to be. Is it possible that wireless is not even needed to do the job? Is it also possible that the nodes described do not really need to be external?
Go to the damn pet store, get a well built wooden doghouse, put a lockable door on the front, and there ya go. Just make a small hole on the back (which should have a few inches of cover from the overhang of the roof), and run a longwire from the wavelan inside the house to a nearby pole.
Doghouses are DESIGNED to withstand the elements! Just ask Sparky...
(Woof.)
-Lx?
Try this: DRS Rugged Systems
No affiliation......etc
Being a WaveLan tech here in Oklahoma City I know WaveLan quite well. The way that the system is build a PC would have no means to create a cell. That is what the firmware on the AccessPoint is for. Frequency, WaveLan Network Name, Protocal Axing ect. A NEMA enclousure is only $2,000.00 and the WavePoint II is only $995.00 currently. A PC may be able to do adhoc mode but that is really just a small Point to Point frequency hopping set up.
PCs definately aren't designed to be all weather machines, but with a little bit of clever planning this could be changed.
The first problem that I can see is the power supply (on standard cases). The cooling fan is designed to be nice and open for greater airflow. This will also allow water into the case.
To get around this problem you will have to directly supply the computer with the necessary voltages.
Since this will be an outdoor machine, you're obviously going to have to have a watertight case. This will cause some heat problems. You're going to need a cpu that does not put out alot of heat. Unfortunately that also means a slow cpu. You're probably looking at double digit megahertz.
Also the motors on hard disks can put out quite a bit of heat. Look into some sort of flash disk.
Finally you're still going to have to disapate the heat that you do make. One way to do this could be wrapping metal tubing around the computer and pumping water through them and a radiator.
These are just ideas I came up with on the spur of the moment. I hope I was of help.
"Reality is less than television."-Brian Oblivion
Isn't that why the iMac was created?
Sheepdot: Open Source good, Closed Source baaaaaaad!
This might not even be that big an issue...or one that has been resolved many times over -- but I don't know the answer, so I'm curious.
How does an air-tight (weather tight) machine deal with being opened? I know with many watch casings, the water-tight seal is rendered useless if the seal is broken once. The watch will still work if the case is closed...but water can then get in. IS this an issue with some of these cases? Hardware will go bad...so it must be replaced. But then again, if the hardware needs to be replaced, it'd probably be a good time to replace the case as well...am I wrong?
Step 1: Find a roadside telephone booth in an unpopulated scenic location.
Step 2: Spend the next ten years trying to convince the local telephone company that the booth is haunted.
Step 3: When telco sends someone out to have a look, have holographic projection equipment ready.
Step 4: If successful at scaring pants off service tech, say you are a researcher studying "psycho-plasma", and offer to buy the booth for ten bucks.
Step 5: Mission accomplished. Rugged weatherproof case obtained.
Seriously, some other guy had a franchise to put kiosks out on sidewalks here, and that never got off, ur, on the ground, either 8-). New York is like a prisoner's dilemma game where the players are always new; there's no such thing as the public interest anymore.
See if you can snag a few of their shoeboxes. Place your main server indoors somewhere and leave the outdoor packet-hopping to a proven technology.
Ricochet
I don't know about software and licensing, but it sounds to me like you're reinventing the wheel.
If You could get your hands on one, these might fit your bill Rugged Laptops from Itronix
Step 1: Buy a case Step 2: Buy some trash bags Step 3: Put the computer inside the trashbag Step 4: Make a hole for cables Yeah, how's that?
There are lots of embedded computing devices that run linux. Motoroloa even makes some that run LinuxPPC. The trick is to get embedded hardware that runs cool enough that you could enclose it in an element proof case. Think about those call boxes on the side of freeways. They protect equipment while allowing access for maintainance, and is a non-integral component, thus adding fault-tolerance to the system.
"Let him go, Ralph. He knows what he's doing." --Otto Mann (simpsons)
I am in Fairbanks, Alaska (from Southern California) and I am having serious troubles overclocking my dual Celery 366 box [I bought a cheap $35 case that has absolutely no airflow except the tiny fan in the back]. I was thinking since now I'm staying at my dad's place for Christmas I could possibly set this baby right outside the door (-35F anyone? :) and massively overclock it to something like 650mhz.
... and
:)
My main questions are:
How do I avoid condensation?
How do I avoid causing freezing damage to the other parts? i.e., hard drive etc
Please also reply to stifle33@hotmail.com if you can help. Thanks.
We just modified a computer for use in an observatory. We'll be posting the instructions soon. It combines temp and humidity control. So far, in the cold, it's done great! It's designed to stay within the specs of the motherboard and other parts.
After browsing a few of these I think I may have something... You should use a case within a case.
The 'inside case' will be sealed, only power wires, antenna and whatever other connectors should leave it. In there you have a temperature triggered Peltier cooler with the hot side on the outside of the inside box. This will allow some cooling to keep it all from frying in the cpu box. In addition, make everything solid state and pack the pupppy with silica gel so that there is no possibility of moisture condensing (hopefully you pack it in a dry environment to mimize this anyhow.) Also, a possibility is: can you reverse the polarity on the peltier to heat the inside case/cpu if you live in antarctica?
(Also an additional thought for the inside case: double layered enclosure with silicon (or other temp insulator) between the two layers of metal case. You attach the 'outside' part of the peltier to the outer panel directly, so that you are not fighting yourself and trying to heat the case while chilling its' contents, or vice versa. Hopefully the insulation will let the outer one dissipate heat/cold and let the inside layer stay at a respectable temperature.)
You have a couple of options for the outside box. All this is for is to circulate air over the inside box and provide for some extreme weather/bb-gun attacks. You could make it a large dingamabobber with a fan (do they sell outdoor fans?) or something like that to normalize the temperature. Or you can try to utilize chimney properties to create currents across the inner box.
This way, you should be able to have a sealed enclosure that is relatively well shielded from the elements. Additionally, if all you are doing is repeating a 100Mb/s signal a small 486 chip should prolly be good enough for you, and that will be relatively secure at various temperatures. (And I think the company that made the 'smallest apache server' shown somewhere on slashdot a few months ago said they were planning on making their PC-on-a-SIMM a reality with low power consumption and a 486 with enough RAM to do you well.)
One question for you is also monitoring? You may want to look into giving each of these 'repeaters' a valid IP address, and use SNMP to measure temperatures, faults, and other such data.
-Steve
My intelligence insults itself.
Hmmm...if the machine is outside, you will need to run a power cable to it, correct? If you're running a power cable out to the computer, why not just have the computer inside and run a longer cable out to the antenna?
Some ideas that might do you some good when dealing with your environment:
1) Give the case a rain-cover. Sure, if you buy a good water-tight case, it's water-tight, but you help immensely by putting a small angled roof over any exposed metal that's not 100% stainless.
2) Find some high-grade cooling fins (fins with an "i", not fans) to put on the box, and mount the hottest components the lowest in the case so they don't become a heat concentration in summer sunlight.
3) The outside of the case will doubtless be a hardshell material. If you can shelter the box (honestly, a large birdhouse roof would be enough) from direct sunlight, you'll extend its life immensely.
4) Come up with some code that keeps the hard drive "spun up," to avoid damaging parts on startup in the winter--just like in Alaska, where (I've heard) they leave some trucks running all winter. It's bad for the truck, but not as bad as having the pistons freeze to the cylinder walls. You could even have the processor crunch some heavy heavy numbers between clock cycles, just to keep the whole thing warm!
5) If you're ultra-paranoid, it's pretty easy to buy humidity and temperature probes for a computer. Since they're already networked, why not have them send status reports if their working conditions suck?
6) You may want one cooling fan internally. It won't do anything except keep the air moving, but that will increase your convection coefficient and keep the air around the processors from getting too hot. It will also increase heat loss via any cooling fins you mount.
Hope this helps.
--jurph
Why not use one of the existing 802.11 wireless-to-ether bridges that exist and hide it all in something watertight like one of those sprinkler controller boxes? Then all you need to run outside is power and a cat5 line.
There are numerous products that do this. Check out:
Proxim's ethernet bridge
WebGear Aviator Pro Access Point
You could probably throw together a PC-based solution for the same cost as one of these items. On the other hand, these dissipate little heat (no trouble sinking heat from the enclosure) and have no moving parts (operational temp range is most likely much higher). And since they're turn key products, you don't have to worry about adminning another box.
As a side note: I bought myself a pair of WebGear Aviator 2.4 wireless cards from CompUSA for $139.99 with a $40 rebate. They kick all ass. I can get a connection to my desktop from my notebook from anywhere in the house. Range and coverage are excellent. They do full IEEE 802.11 and there's Linux drivers (read SUPPORTED.CARDS in the root of pcmcia_cs sources) that work pretty well. Couch surfing for everyone!
That exchange brightened an old fart's day.
the lopht and other groups have been working on creating a encrypted network using wavelans for for short range and ham radios for long range networking. They are using free operating systems such as linux on the network nodes. Some more information is at http://www.l0pht.com/~oblivion/radionet/radionet.h tml
Another place to try - http://www.icsadvent.com/
Their headquarters is down the street from me - I've worked with them to create enclosures for the computers onboard a hazardous materials fire truck... pricey, but good stuff.
That's what we did on the univ with a radiometer meant for some very hot countries.
The small fridge allows heat to go out, but no air goes in or out. Thus, your computer won't collect any dust, and keep cool.
GCS/MU d- s+: a- C++$ USH++$ P- L+> E W++$ N o-- K- W++@ O-- M- !V PS Y+ PGP- t+ 5(+) X- R tv? b++++ y++(+++)
Most of DSSS (direct sequence spread spectrum) adapters use the same signal spectrum for the two directions. By using spread spectrum several 'channels' can transmit at the same time without interference provided they are using different orthogonal chip sequences. Anyway, Common wireless adapters are only half-duplex so no bidirectional transmission happens.
What about solar power? Where do you get the charging controllers and the multi-voltage (+/-12v and +/-5v) from off of this single source?