All users should definatley check out Stanford's IBE Secure E-Mail system (link) - AKA "IdentiCrypt". This would be a great use of such a distributed security model some people are proposing.
With this system, email can be encrypted using an easily obtainable public key (no need to exchange keys beforehand) - the string "your@email.address". You can encrypt email to people that have not yet set up a key, just by knowing their email address. To decrypt, they grab their key from a server. You can request your key from Stanford's key servers. These would one day be replaced by a publicly-trusted resource.
An elliptic curve variant of the Diffie-Hellman encryption model is used. A third party is necessary for the system and the distributed storage solutions being proposed could make good use of this technology.
Read a technical description here or download here.
This is an EXCELENT idea!!!! You must tell people about this. Drive a PC speaker directly - with a LED that indicates "there is an error somewhere - hook up your PC speaker to hear it." Would even work on a headless box!
Seems it might pay sometime to RTFM. You could have saved you and your dad a lot of time, trouble and data.....
I know - Hindsight is usually pretty damn good - but it's a good point to be made - in general. Be farmiliar with what your dealing with in order to set it up and diagnose properly.
It has long been debated which effect is more prominent with air as the fluid. Introductory textbooks on aircraft airodynamics tend to state the pressure differential as the cause of lift; while in practice, it many times is more so an effect related to the attack angle - true.
Don't believe everything you read - even if it comes from a textbook. Check out the link for an interesting JavaApplet!!! Pretty neat.
Good point though. I'm sure attack angle would be even more prominent with water. I was just curious if non-compressable fluids do the same as compressable with a wing-type configuration (as far as the pressure differential goes).
...and one already exists that could "fly" under the Pacific from Seattle to Tokyo on a penlight battery!
And how long would this take???
BTW, anyone have insights as to how "wings" work in incompressible fluids such as water? Do you get the same pressure drop from increased velocity above the wing as you do in air? Though a compressable gas ballast is usually the prefered method of producing 'lift' underwater, could you forgo lighter-than-water substances within the hull of an underwater vessel in favor of using "wings?"
> I always have wondered about the actual effect that talking/writing to your representitives has had. It seems like, at least in this case, the decision against it was based almost entirely around citizen outrage.... [petree:#3319491]
This is a real demonstration of the power that large group of people, living in a democratic society, can actually impart on their government. We all know it doesn't happen that often. We've all seen scary bills come up - and pass, again and again. Just like that. Done. New law. More restrictions. Your life is now different. More words in the books to prevent what you can do - as a citizen - legally. Forced into submission. Why these new laws? Here's your answer: Lobbyists.
We just sit there an let it happen. The lobbyists are paid to sweet-talk out lawmakers. Tell them it's 'A good idea for the people', 'it's the right thing to do' or that 'this will protect the good people; the god-fearing, law abiding, tax-paying citizens, from the scum of the earth - the good ones are the people you're working for sir.'
These lawmakers listen to them - the lobbyists - BECAUSE THEY ARE THE ONLY ONES SPEAKING!!!
People - if there's a law out there you don't like - do something people have been doing for hundreds of years. Do something very simple. Tell that person that makes the laws that you don't like what they are doing. Be honest with your lawmaker (in writing - handwritten) and tell them what you think. Just express your opinion. Takes 10 minutes (or longer - if you'd like). Get out a piece of paper and a pen. Blank page - but don't be scared. You can do this - even if you never have before.
This is what our government is really about, remember? They are called "Representatives." Remember that word? You learned it in 4th grade - when Mrs. Crabapple told you about the various branches of government, and the checks and balances, and the lifecycle of something called a "bill." Ok think back to that. These people are representatives - that we elect - to us in the house of government. They represennt us - but they need to know how we feel!
Forget the government you know of today. The one where things just happen and it feels like you have no control. These people are supposed to be representing you..... No - not the YOUr city, or the YOUr county, or YOUr voting district.... You as in YOU [insert your name here] - an individual. A person with thoughts and feelings, with bills to pay, with kids to take to soccer practice, with laws to abide by. You are the ones that matter. You are the ones that pay the bills - pay their salary! They better listen to you.
>Now is not the time to get complacent. That will doom us more than anything else. Keep sending those letters, making those phone calls, and talking with friends and colleagues. If we can get their attention by doing what we've done so far, we can do much more if we take this to the next level.[SomeoneYouDontKnow:#3319793]
Who makes these laws?
Lobbyists make these laws and they think they are protecting you. Often they are. But more than often - they have NO IDEA ABOUT THE LAWS THEY ARE INTRODUCING. And who's the expert? - you. You're obviously concerned about it? Right?............. Well then.....<nudgeNudge> go ahead. Tell him. (or her) Do it in writing and encourage others to do the same!
Ok - now. Remember that paper and pen you got out? Right. Now set them down in front of you - ok... Now write on the paper - in nice, neat letters: "Dear <insert your representative's name here>,"
Good start. Now - tell him (or her - please rinse/repeat ther "her" thing throughout) which bill he has recently introduced that you will be refering to, why, or what parts of his decision you may support, OR would support his decision IF <insert modified clause here>, then tell him the things you don't like about it. Continue with how such a bill, if introduced, would change the way you live, would limit your freedoms, or would cause you undue stress or unfair setbacks. Plead with them to reconsider the bill in it's current state and to either drop it alltogether or modify certain clauses to cause you less distress or potential problems.
What we all need to do is share our views with our representatives when we hear about a bill we don't want passed. I have alway thought that I wouldn't have much of an impact on my government decision-makers because I am only one person - one voice - on letter of angst. But obviously, as we've seen tonight, the common man can make a difference - IF HE SPEAKS LOUDLY ENOUGH. Raise a hussy. Tell them you don't like it! Be honest - it's your governement too!
Heck - even if they end up passing the law - too much big money pressure - you can at least make them feel guilty about it. I know - the torture we put these guys through:) Just remember - they are supposed to be working for us - not JUST big money. Remind them of that. Give them your sob story. --AND DO IT IN HANDWRITING--
Yes --DO IT IN HANDWRITING--
Tell them you don't like their law. Tell them you know lots of other people in your comunity, or at work, or at PTA meetings, that feel the same way (if such a thing is true). Just be honest and put down what you'd like to say to them. Dont' be rude. Be civil and professional and express yourself in writing your feelings about their bill. (or about someone elses bill they will be voting on).
If you've got somthing to say - fscking say it. Express your disapproval. Write your representatives. 10 minutes and a stamp. Take a night off of watching one TV show. (It's empowering to do something useful - for you and your country/county/state/whatever instead of watching advertisements and listening to laugh tracks).
If you think that just one person can't have a big impact, try going to bed with a mosquito.
I was curious about what kind of hardware in the x86 arena had the same capabilities. Does anyone know where one could find a rundown of the "extras" found on the various x86-based processors with capabilities similar to those described above?
How do they compare to the AltiVec in terms of speed, precision, cache in/out, etc.?
And why doesn't anyone besides Apple sell this stuff?? Is is possible to get a G4-enabled, AltiVec-enabled board somewhere without paying the Apple Tax?
I think something like http://bleachedmeat.org would be a good domain name for a site like this. Much easier to type!
Re:Ahh - yes.... Batteries....
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· Score: 2
Sure... It's a notebook. But it's not a notebook that's going into your briefcase, your backpack, or your carryon like a 'notebook' does. It weighs 30 pounds, is built into a toolbox, and you can actually service it yourself! You don't need PCMCIA/CardBus peripheral devices (no need to pay the 'mobile tax'), can use real harddrives, even a decent video adapter or soundboard.
I probably wouldn't call it a notebook - but you can call it anything you'd like:)
Well.... What's your typical toolbox weigh? I've got a few that weigh at least that. I never called the thing a laptop - and this'd be much more powerful than your 286, and this could run on batteries (well - maybe for a few minutes anyway). I had one of those Compaq's too. Had to plug it into the wall - and it was next to useless as a computer (what? - 20Meg HD? - 286 won't run most of the free unix derivatives....) ==Really cool plasma display though, eh?==:)
So 'practicality' is dependant on this intended use. As something you can throw in your briefcase or backpack - no. As a more-or-less complete machine, that's servicable, low profile, has a built in handle, you can throw real hardware into (debugging the flaky network card that's in your machine in the cage at the colo...), and easily upgradeable - then well... you decide.
I think it'd make a great field machine. I work in greenhouse reasearch. Sometimes having a real computer as portable as this could be a real benefit. - the ability to throw an A/D card into something like this in the field to log thermocouple measurements, or for example when you need more than 2 serial ports on a single machine. Our lab has handfuls of old serial port cards - no PCMCIA serial cards and dongles laying around though.... I think this is pretty neat - at least for industrial work, computer repair/network diagnosis, hobby computer technician, or even just the handyman that can use computers to solve problems.... Great idea on the part of this ArsMan....Nicely done.
Ahh - yes.... Batteries....
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· Score: 3, Informative
Wow! You are so correct! One could construct this such that either a normal powersupply (one you connect to the wall) OR a battery based power source (wired into the original supply as you state) could power the thing. You could also quite easily build a regulator circut and employ the use of some switchers and or linear devices (free samples at National Semiconductor) to provide all your voltages from 12 or 24V. Not bad.... Just put as many battery packs in there as you can fit/cary and wire them in parallel! Construct a charger circuit that tops off the batteries whenever you're plugged into the wall!... bingo!
Yes you are very correct. 12vDC->120vAC then back again, all within the same box - bad. 12vDC -> directly to the board, with some regulators to produce your +-5v, etc. - good.
Congratulations! You have just built your self a... (rather crapy) laptop!
Sorry couldn't resist.
True. Very true (you made me smile). But the best part about something like this is that I can use PCI/AGP cards! It's portable - and with a little flat screen built into the top lid, keyboard resting inside....
Well it wouldn't exactly be a laptop - but you sure could put it on a table - and you could get REAL video, real sound, do video capture, throw a DAQ card in there, etc. - WIHTOUT paying the PCIMCIA/CardBus tax.....
Pretty Slick
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· Score: 4, Interesting
This would make a pretty nice addition to my collection of toolboxen. I have a couple different tool sets configured for working on a different variety of things (boxes I take to my friends' houses when they have this kind of trouble or that...). Sometimes I end up taking along multiple boxes because I just don't feel like switching things around (and it's good to have more tools at your disposal anyway - you never know!) But someone with a computer problem - just throw this baby in the trunk and go!
Ok, well don't 'throw' it. If (not 'if' but 'when') I build one of these, I'll be sure to add some shock protection to the mobo and CD drive. A keyboard holder inside the unit would be pretty nice too. Carry it all in one go. Fit an inexpensive flatscreen inside the cover case you've no CRT to hook up to and you're good to go.
Dual 12V battery pack with inverter could go in there too...
5 People
3 Afternoons
1 Huge Pile of Code
2 Large White-boards
3 small little cubes of those MultiColored post-ITs
2 Handfuls of assorted colors DryErase markers
Start by pouring all the ingredents into a medium sized classroom-type-room with lots of chairs and a small assortment of refreshments. (Be sure to wash off the white board.) Tell all the people what you are trying to do and tell them they will have to help you out for at least one afternoon over the next couple of days. [Whatever. Intimate time with code. They'll learn something. You'll get to talk to eachother.] Tell some they have to stay, others they'll have to help you tomorrow, etc. Look over the code and decide which portion you'd like to work with today. Isn't it pretty? Now - by applying the markers and the PostITs to the White-board, carefully extract the useful parts of the code, leaving the nasty, hairy choke behind. Go for the structure. Go for the connections. Dispose what is leftover. Take a high resolution picture. Go home and get some sleep.
Repeat the above for each piece of the program you'd like to work on for each particular day. After you have extracted all the good, and none of the bad, combine the extract with your wonderful programming skills, the sarcastic cheers from your friends in nearby cubicles, and big high-resolution printouts of your photography work in a CPU Unit Processor, blending until firm. Chill, Serve and Enjoy!
You may need to configure one machine separately from the others to be the "master." You'll probably need either some kind of disk space availible or use some sort of ramdrive.
From the Mosix web page:
How to configure MOSIX clusters with a pool of servers and a set of (personal) workstations:
Single-pool = all the servers and workstations are used as a single cluster: install the same "mosix.map" in all the computers, with the IP addresses of all the computers.
Advantage/disadvantage: your workstation is part of the pool.
Server-pool = servers are shared while workstations are not part of the cluster: install the same "mosix.map" in all the servers, with the IP addresses of only the servers.
Advantage/disadvantage: remote processes will not move to your workstation. You need to login to one of the servers to use the cluster.
Adaptive-pool = servers are shared while workstations join or leave the cluster, e.g. from 5PM to 8AM: install the same "mosix.map" in all the computers, with the IP
addresses of all the servers and workstations, then use a simple script, to decide whether MOSIX should be activated or deactivated.
Advantage/disadvantage: remote processes can use your workstation when you are not using it.
I'm there. Unix when you're high is a treat. Playing with my FreeBSD box after a bowl or two is a great way to satiate either the anti-social [sit there in front of your computer for hours without having to talk to anybody] or super-social [email, and lots of it] person you may become. While there are many other things I can enjoy under the influence, unix is a treat for me.
I love to build - and I especially like to be crafty and work with my hands after a nice J with some friends. I like to build, fix, and create. And while marijuana can make you pretty spacy, it often helps me to concentrate - and become less distractable than I usually am. I can give myself a little project, or part of a big one, and just go at it.
The slight change in perspective at the command line can be a benefit too. Seeing problems and relations between system resources in a different way can help anyone become a better sysadmin or to better solve problems that may develop. Stepping off your own beaten path can lead to shortcuts and enlightenment. You may realize you've been taking the long way home on a simple function you've been performing for years. A chance to explore - that's what it's really all about.
While I don't suggest relying on yourself when you're very high or whipping out a J at work - if you never use your computer when you smoke - or if you used to smoke long ago, but haven't in a while... well - give it a shot. Explore. If it doesn't work for you... well, you probably haven't lost much. And it's pretty hard to experiment without learning _something_ right?
Just remember to dose yoruself properly. Don't do too much - or you'll just stare at your screen and call me crazy. Use your command history - and keep an editor window open to jot down ideas or help you remember what you've done. [Short term memory IS affected - so compensate!]
You might try building a device like this which would allow you to interface directly with the drive controller. [If you don't need something as complex as shown at that link, I'm sure with the references linked from there, you could put together something].
By doing this, you could apply power to your drives before you boot, and use something similar to what's described above to spin them up.
This would allow you to control the high current draw by spinning the drives up in whatever order you'd like before you electrically remove the "spinner-upper" from the drive electronics and allow the computer to boot normally. (This is assuming that a 2nd spin-up signal from the BIOS wouldn't freak out the drive.)
You can find an IDE Hardware Reference & Information Document here.
To be very honest, I can't really see anybody implementing something as complex and convoluted as what's described above, particularly for multiple drives - but a properly programmed PIC chip or development board, with a bunch of IDE headers for the drives, that could spin up the drives however you'd like, then pass-through the original IDE signals from the motherboard, at boot time - POTENTIALLY, Potentially Could... save you the forty bucks an additional PS would cost you....:)
You can see another suggestion of mine for this project here.
Though I agree with you that perhaps some form of battery may be a better solution, I highly doubt that current drain would remain at 1/2 Amp for 5 seconds. I just can't see that happening.
It would greatly depend on the individual drive and I'm guessing the max current drain of 570mA would only be required initially, and for a very short period of time. I'd imagine the draw would drop off at an exponential rate for maybe 3 seconds total on a modern drive as the platters gain momentum. [It'd be fun to plot right?]
Plotting the current draw as one of the drives spins up, integrating over the time of increased draw, and multiplying by the number of drives to get a Coulomb would be a much better way of deciding what kind of caps are needed than assuming they would draw 1/2 amp for 5 seconds each...
Put one on each the +5 and +12 volt rails going to your drives. Be sure they're charged and isolated from leakage before powering up the system.
You could do a 2 stage power-up for your system. 1st stage uses the regular switch on your powersupply and does nothing but charge up the caps. Second stage is when you actually apply power to the motherboard and all your drives inside. This would require a separate switch that could turn on/off all the +-5 and +-12 volt legs necessary. A few relays or solid-state relays would do nicely, perhaps a plain triac or SCR on each would do, but you'd need to do some reasearch on those. I haven't messed with them for some time now.
After you hit the 2nd switch, the drives would get the current they need from both the caps and the regular [underpowered] supply.
Of course this is all a bit more work than just getting another small powersupply for $15 or so like everyone else is suggesting -- but you asked the question.
Being a licensed radio amateur (holding a General ticket), this post interested me in that respect.
A quick google search for "dish array" took me here which explains some of the basics of dealing with dish arrays.
One thing I was considering is not using the dishes to look randomly to space hoping to sniff some martian communications, but to somehow extract some known low level signal from somewhere - how about the moon? Amateurs sometimes bounce signals off the moon for communication. Really! Do a search for moon bounce, find out the frequencies often used, and see if you can construct an array.
I know I made that sound _really_ simple, but I'm sure it wouldn't be. I think the frequencies involved would significantly complicate using those small dishes and the supplied LNBs (or whatever the receiving elements they use these days are called). Anyway, it's something to look into.
I'd also suggest looking into ways in which you could turn an array into some sort of radar receiver. Lay them out correctly pointing to the sky and bathe some clouds with radar signals. Try to image the cloud densities, determine their height, etc.
Put them on the wall of a high building for weak-signal microwave receive.
Slashdot Mirror
Read about using a flux capacitor connected to your parallel port here. This setup can be used to avert your biggest problem, boring weekends.
With this system, email can be encrypted using an easily obtainable public key (no need to exchange keys beforehand) - the string "your@email.address". You can encrypt email to people that have not yet set up a key, just by knowing their email address. To decrypt, they grab their key from a server. You can request your key from Stanford's key servers. These would one day be replaced by a publicly-trusted resource.
An elliptic curve variant of the Diffie-Hellman encryption model is used. A third party is necessary for the system and the distributed storage solutions being proposed could make good use of this technology.
Read a technical description here or download here.
Wow!
I know - Hindsight is usually pretty damn good - but it's a good point to be made - in general. Be farmiliar with what your dealing with in order to set it up and diagnose properly.
True, sucky design, but you should have known.
Don't believe everything you read - even if it comes from a textbook. Check out the link for an interesting JavaApplet!!! Pretty neat.
Good point though. I'm sure attack angle would be even more prominent with water. I was just curious if non-compressable fluids do the same as compressable with a wing-type configuration (as far as the pressure differential goes).
...and one already exists that could "fly" under the Pacific from Seattle to Tokyo on a penlight battery!
And how long would this take???
BTW, anyone have insights as to how "wings" work in incompressible fluids such as water? Do you get the same pressure drop from increased velocity above the wing as you do in air? Though a compressable gas ballast is usually the prefered method of producing 'lift' underwater, could you forgo lighter-than-water substances within the hull of an underwater vessel in favor of using "wings?"
> I always have wondered about the actual effect that talking/writing to your representitives has had. It seems like, at least in this case, the decision against it was based almost entirely around citizen outrage. ... [petree:#3319491]
This is a real demonstration of the power that large group of people, living in a democratic society, can actually impart on their government. We all know it doesn't happen that often. We've all seen scary bills come up - and pass, again and again. Just like that. Done. New law. More restrictions. Your life is now different. More words in the books to prevent what you can do - as a citizen - legally. Forced into submission. Why these new laws? Here's your answer: Lobbyists.
We just sit there an let it happen. The lobbyists are paid to sweet-talk out lawmakers. Tell them it's 'A good idea for the people', 'it's the right thing to do' or that 'this will protect the good people; the god-fearing, law abiding, tax-paying citizens, from the scum of the earth - the good ones are the people you're working for sir.'
These lawmakers listen to them - the lobbyists - BECAUSE THEY ARE THE ONLY ONES SPEAKING!!!
People - if there's a law out there you don't like - do something people have been doing for hundreds of years. Do something very simple. Tell that person that makes the laws that you don't like what they are doing. Be honest with your lawmaker (in writing - handwritten) and tell them what you think. Just express your opinion. Takes 10 minutes (or longer - if you'd like). Get out a piece of paper and a pen. Blank page - but don't be scared. You can do this - even if you never have before.
This is what our government is really about, remember? They are called "Representatives." Remember that word? You learned it in 4th grade - when Mrs. Crabapple told you about the various branches of government, and the checks and balances, and the lifecycle of something called a "bill." Ok think back to that. These people are representatives - that we elect - to us in the house of government. They represennt us - but they need to know how we feel!
Forget the government you know of today. The one where things just happen and it feels like you have no control. These people are supposed to be representing you..... No - not the YOUr city, or the YOUr county, or YOUr voting district.... You as in YOU [insert your name here] - an individual. A person with thoughts and feelings, with bills to pay, with kids to take to soccer practice, with laws to abide by. You are the ones that matter. You are the ones that pay the bills - pay their salary! They better listen to you.
>Now is not the time to get complacent. That will doom us more than anything else. Keep sending those letters, making those phone calls, and talking with friends and colleagues. If we can get their attention by doing what we've done so far, we can do much more if we take this to the next level.[SomeoneYouDontKnow:#3319793]
Who makes these laws?
Lobbyists make these laws and they think they are protecting you. Often they are. But more than often - they have NO IDEA ABOUT THE LAWS THEY ARE INTRODUCING. And who's the expert? - you. You're obviously concerned about it? Right?............. Well then.....<nudgeNudge> go ahead. Tell him. (or her) Do it in writing and encourage others to do the same!
Ok - now. Remember that paper and pen you got out? Right. Now set them down in front of you - ok... Now write on the paper - in nice, neat letters: "Dear <insert your representative's name here>,"
Good start. Now - tell him (or her - please rinse/repeat ther "her" thing throughout) which bill he has recently introduced that you will be refering to, why, or what parts of his decision you may support, OR would support his decision IF <insert modified clause here>, then tell him the things you don't like about it. Continue with how such a bill, if introduced, would change the way you live, would limit your freedoms, or would cause you undue stress or unfair setbacks. Plead with them to reconsider the bill in it's current state and to either drop it alltogether or modify certain clauses to cause you less distress or potential problems. What we all need to do is share our views with our representatives when we hear about a bill we don't want passed. I have alway thought that I wouldn't have much of an impact on my government decision-makers because I am only one person - one voice - on letter of angst. But obviously, as we've seen tonight, the common man can make a difference - IF HE SPEAKS LOUDLY ENOUGH. Raise a hussy. Tell them you don't like it! Be honest - it's your governement too!
Heck - even if they end up passing the law - too much big money pressure - you can at least make them feel guilty about it. I know - the torture we put these guys through :) Just remember - they are supposed to be working for us - not JUST big money. Remind them of that. Give them your sob story. --AND DO IT IN HANDWRITING--
Yes --DO IT IN HANDWRITING--
Tell them you don't like their law. Tell them you know lots of other people in your comunity, or at work, or at PTA meetings, that feel the same way (if such a thing is true). Just be honest and put down what you'd like to say to them. Dont' be rude. Be civil and professional and express yourself in writing your feelings about their bill. (or about someone elses bill they will be voting on).
If you've got somthing to say - fscking say it. Express your disapproval. Write your representatives. 10 minutes and a stamp. Take a night off of watching one TV show. (It's empowering to do something useful - for you and your country/county/state/whatever instead of watching advertisements and listening to laugh tracks).
If you think that just one person can't have a big impact, try going to bed with a mosquito.
Funny... I suppose you think you're doing people a service.
I was curious about what kind of hardware in the x86 arena had the same capabilities. Does anyone know where one could find a rundown of the "extras" found on the various x86-based processors with capabilities similar to those described above?
How do they compare to the AltiVec in terms of speed, precision, cache in/out, etc.?
Oh! http://www.processor-emporium.co.uk seems to be a good reference site....
And why doesn't anyone besides Apple sell this stuff?? Is is possible to get a G4-enabled, AltiVec-enabled board somewhere without paying the Apple Tax?
Explain the "farad" temperature measurement please....
I think something like http://bleachedmeat.org would be a good domain name for a site like this. Much easier to type!
Sure ... It's a notebook. But it's not a notebook that's going into your briefcase, your backpack, or your carryon like a 'notebook' does. It weighs 30 pounds, is built into a toolbox, and you can actually service it yourself! You don't need PCMCIA/CardBus peripheral devices (no need to pay the 'mobile tax'), can use real harddrives, even a decent video adapter or soundboard.
I probably wouldn't call it a notebook - but you can call it anything you'd like:)
Well.... What's your typical toolbox weigh? I've got a few that weigh at least that. I never called the thing a laptop - and this'd be much more powerful than your 286, and this could run on batteries (well - maybe for a few minutes anyway). I had one of those Compaq's too. Had to plug it into the wall - and it was next to useless as a computer (what? - 20Meg HD? - 286 won't run most of the free unix derivatives....) ==Really cool plasma display though, eh?==:)
So 'practicality' is dependant on this intended use. As something you can throw in your briefcase or backpack - no. As a more-or-less complete machine, that's servicable, low profile, has a built in handle, you can throw real hardware into (debugging the flaky network card that's in your machine in the cage at the colo...), and easily upgradeable - then well... you decide.
I think it'd make a great field machine. I work in greenhouse reasearch. Sometimes having a real computer as portable as this could be a real benefit. - the ability to throw an A/D card into something like this in the field to log thermocouple measurements, or for example when you need more than 2 serial ports on a single machine. Our lab has handfuls of old serial port cards - no PCMCIA serial cards and dongles laying around though.... I think this is pretty neat - at least for industrial work, computer repair/network diagnosis, hobby computer technician, or even just the handyman that can use computers to solve problems.... Great idea on the part of this ArsMan....Nicely done.
Wow! You are so correct! One could construct this such that either a normal powersupply (one you connect to the wall) OR a battery based power source (wired into the original supply as you state) could power the thing. You could also quite easily build a regulator circut and employ the use of some switchers and or linear devices (free samples at National Semiconductor) to provide all your voltages from 12 or 24V. Not bad.... Just put as many battery packs in there as you can fit/cary and wire them in parallel! Construct a charger circuit that tops off the batteries whenever you're plugged into the wall! ... bingo!
Yes you are very correct. 12vDC->120vAC then back again, all within the same box - bad. 12vDC -> directly to the board, with some regulators to produce your +-5v, etc. - good.
Congratulations! You have just built your self a
Sorry couldn't resist.
True. Very true (you made me smile). But the best part about something like this is that I can use PCI/AGP cards! It's portable - and with a little flat screen built into the top lid, keyboard resting inside....
Well it wouldn't exactly be a laptop - but you sure could put it on a table - and you could get REAL video, real sound, do video capture, throw a DAQ card in there, etc. - WIHTOUT paying the PCIMCIA/CardBus tax.....
This would make a pretty nice addition to my collection of toolboxen. I have a couple different tool sets configured for working on a different variety of things (boxes I take to my friends' houses when they have this kind of trouble or that...). Sometimes I end up taking along multiple boxes because I just don't feel like switching things around (and it's good to have more tools at your disposal anyway - you never know!) But someone with a computer problem - just throw this baby in the trunk and go!
Ok, well don't 'throw' it. If (not 'if' but 'when') I build one of these, I'll be sure to add some shock protection to the mobo and CD drive. A keyboard holder inside the unit would be pretty nice too. Carry it all in one go. Fit an inexpensive flatscreen inside the cover case you've no CRT to hook up to and you're good to go.
Dual 12V battery pack with inverter could go in there too...
5 People
3 Afternoons
1 Huge Pile of Code
2 Large White-boards
3 small little cubes of those MultiColored post-ITs
2 Handfuls of assorted colors DryErase markers
Start by pouring all the ingredents into a medium sized classroom-type-room with lots of chairs and a small assortment of refreshments. (Be sure to wash off the white board.) Tell all the people what you are trying to do and tell them they will have to help you out for at least one afternoon over the next couple of days. [Whatever. Intimate time with code. They'll learn something. You'll get to talk to eachother.] Tell some they have to stay, others they'll have to help you tomorrow, etc. Look over the code and decide which portion you'd like to work with today. Isn't it pretty? Now - by applying the markers and the PostITs to the White-board, carefully extract the useful parts of the code, leaving the nasty, hairy choke behind. Go for the structure. Go for the connections. Dispose what is leftover. Take a high resolution picture. Go home and get some sleep.
Repeat the above for each piece of the program you'd like to work on for each particular day. After you have extracted all the good, and none of the bad, combine the extract with your wonderful programming skills, the sarcastic cheers from your friends in nearby cubicles, and big high-resolution printouts of your photography work in a CPU Unit Processor, blending until firm. Chill, Serve and Enjoy!
"Mosix"
You may need to configure one machine separately from the others to be the "master." You'll probably need either some kind of disk space availible or use some sort of ramdrive.
From the Mosix web page:
How to configure MOSIX clusters with a pool of servers and a set of (personal) workstations:
Single-pool = all the servers and workstations are used as a single cluster: install the same "mosix.map" in all the computers, with the IP addresses of all the computers.
Advantage/disadvantage: your workstation is part of the pool.
Server-pool = servers are shared while workstations are not part of the cluster: install the same "mosix.map" in all the servers, with the IP addresses of only the servers.
Advantage/disadvantage: remote processes will not move to your workstation. You need to login to one of the servers to use the cluster.
Adaptive-pool = servers are shared while workstations join or leave the cluster, e.g. from 5PM to 8AM: install the same "mosix.map" in all the computers, with the IP
addresses of all the servers and workstations, then use a simple script, to decide whether MOSIX should be activated or deactivated.
Advantage/disadvantage: remote processes can use your workstation when you are not using it.
Standing applause!!!!
Wish I could mod in a discussion I was participating in!!!
Very nice.
I'm there. Unix when you're high is a treat. Playing with my FreeBSD box after a bowl or two is a great way to satiate either the anti-social [sit there in front of your computer for hours without having to talk to anybody] or super-social [email, and lots of it] person you may become. While there are many other things I can enjoy under the influence, unix is a treat for me.
... well - give it a shot. Explore. If it doesn't work for you... well, you probably haven't lost much. And it's pretty hard to experiment without learning _something_ right?
I love to build - and I especially like to be crafty and work with my hands after a nice J with some friends. I like to build, fix, and create. And while marijuana can make you pretty spacy, it often helps me to concentrate - and become less distractable than I usually am. I can give myself a little project, or part of a big one, and just go at it.
The slight change in perspective at the command line can be a benefit too. Seeing problems and relations between system resources in a different way can help anyone become a better sysadmin or to better solve problems that may develop. Stepping off your own beaten path can lead to shortcuts and enlightenment. You may realize you've been taking the long way home on a simple function you've been performing for years. A chance to explore - that's what it's really all about.
While I don't suggest relying on yourself when you're very high or whipping out a J at work - if you never use your computer when you smoke - or if you used to smoke long ago, but haven't in a while
Just remember to dose yoruself properly. Don't do too much - or you'll just stare at your screen and call me crazy. Use your command history - and keep an editor window open to jot down ideas or help you remember what you've done. [Short term memory IS affected - so compensate!]
Experiment. You're bound to learn _something_
You might try building a device like this which would allow you to interface directly with the drive controller. [If you don't need something as complex as shown at that link, I'm sure with the references linked from there, you could put together something].
... save you the forty bucks an additional PS would cost you.... :)
By doing this, you could apply power to your drives before you boot, and use something similar to what's described above to spin them up.
This would allow you to control the high current draw by spinning the drives up in whatever order you'd like before you electrically remove the "spinner-upper" from the drive electronics and allow the computer to boot normally. (This is assuming that a 2nd spin-up signal from the BIOS wouldn't freak out the drive.)
You can find an IDE Hardware Reference & Information Document here.
To be very honest, I can't really see anybody implementing something as complex and convoluted as what's described above, particularly for multiple drives - but a properly programmed PIC chip or development board, with a bunch of IDE headers for the drives, that could spin up the drives however you'd like, then pass-through the original IDE signals from the motherboard, at boot time - POTENTIALLY, Potentially Could
You can see another suggestion of mine for this project here.
Good luck!
Though I agree with you that perhaps some form of battery may be a better solution, I highly doubt that current drain would remain at 1/2 Amp for 5 seconds. I just can't see that happening.
It would greatly depend on the individual drive and I'm guessing the max current drain of 570mA would only be required initially, and for a very short period of time. I'd imagine the draw would drop off at an exponential rate for maybe 3 seconds total on a modern drive as the platters gain momentum. [It'd be fun to plot right?]
Plotting the current draw as one of the drives spins up, integrating over the time of increased draw, and multiplying by the number of drives to get a Coulomb would be a much better way of deciding what kind of caps are needed than assuming they would draw 1/2 amp for 5 seconds each...
He'll tell you what you need in 2 words:
Big Caps
Put one on each the +5 and +12 volt rails going to your drives. Be sure they're charged and isolated from leakage before powering up the system.
You could do a 2 stage power-up for your system. 1st stage uses the regular switch on your powersupply and does nothing but charge up the caps. Second stage is when you actually apply power to the motherboard and all your drives inside. This would require a separate switch that could turn on/off all the +-5 and +-12 volt legs necessary. A few relays or solid-state relays would do nicely, perhaps a plain triac or SCR on each would do, but you'd need to do some reasearch on those. I haven't messed with them for some time now.
After you hit the 2nd switch, the drives would get the current they need from both the caps and the regular [underpowered] supply.
Of course this is all a bit more work than just getting another small powersupply for $15 or so like everyone else is suggesting -- but you asked the question.
Being a licensed radio amateur (holding a General ticket), this post interested me in that respect.
A quick google search for "dish array" took me here which explains some of the basics of dealing with dish arrays.
One thing I was considering is not using the dishes to look randomly to space hoping to sniff some martian communications, but to somehow extract some known low level signal from somewhere - how about the moon? Amateurs sometimes bounce signals off the moon for communication. Really! Do a search for moon bounce, find out the frequencies often used, and see if you can construct an array.
I know I made that sound _really_ simple, but I'm sure it wouldn't be. I think the frequencies involved would significantly complicate using those small dishes and the supplied LNBs (or whatever the receiving elements they use these days are called). Anyway, it's something to look into.
I'd also suggest looking into ways in which you could turn an array into some sort of radar receiver. Lay them out correctly pointing to the sky and bathe some clouds with radar signals. Try to image the cloud densities, determine their height, etc.
Put them on the wall of a high building for weak-signal microwave receive.
Just some ideas...