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User: dattaway

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  1. Re:Bad career move on BellSouth denies ADSL for Linux users · · Score: 4

    I wasn't satisfied with a computer generated denial because I stated Linux as my OS of choice, so I complained. Here's the intelligent reply from a human I got:

    Date: Fri, 12 Feb 99 15:45:49 -0500
    From: adsl@bellsouth.net
    To: dattaway@ebicom.net
    Subject: Re: BellSouth.net FastAccess ADSL Service Qualification Status (fwd)


    Dear dattaway

    Thank you for your recent e-mail message.

    At this time, our technicians are configuring standard TCP/IP in Windows 95 and NT environments. Although we do not provide
    support for UNIX and LINUX , these platforms should support TCP/IP and Ethernet connections.

    Therefore, it is possible to use ADSL with these types of systems.

    For more information on ADSL access and answers to other questions you may have, please refer to our ADSL home page at the following address:

    http://www.bellsouth.net/external/adsl

    If you have any additional questions or comments, please e-mail us again.

    Adam
    adsl@bellsouth.net

  2. Re:Linux features in NT on Linux Jobs at Microsoft: PR Rep · · Score: 2

    I for one, think it would be a GOOD thing if MICROS~1 added Linux features like reliability, portability, efficiency, low-cost, responsiveness to customer concerns, and quality-control by massive peer review to NT.

    Here's my peer review of the reliability of the job search page:

    Microsoft VBScript runtime error '800a000d'

    Type mismatch: 'cInt'

    /jobs/search/viewJobs.asp, line 283

    --Maybe its just my browser?

  3. Re:Hacking MS's jobs site on Linux Jobs at Microsoft: PR Rep · · Score: 2

    How odd. That page seems to have been disabled!

  4. Re:ISDN prices addendum on 3Com Class Action Suit · · Score: 2

    Its $72 a month when I finally dropped it here in Starkville, Mississippi. Sure, the 15KBps transfer speeds were nice, but with a 56K modem, I hardly know the difference with Netscape. I now pay $25 a month, not the $100 with ISDN (taxes, etc...)

    The real reason I dropped ISDN is that the connection would die about every month or two and getting to a like human on BellSouth's "business" repair line was insane. Once I logged 6 hours on my cell phone to finally to convince them it wasn't my problem and get a tech to get the line fixed. Try getting the runaround and telling every supervisor and department that you put a scope and a meter on the line to prove it was an opened circuit (10 megaohms) with no signal. It was a game I got tired of playing.

    Its analog for me at the moment.

  5. Re:Yea right, and i have a bridge id like to sell on Massive Bandwidth over Powergrids? · · Score: 2

    You might not be able to switch at that speed, but you can modulate on multiple lower frequencies.

    This makes me wonder why consumers just can't use microwaves for high bandwidth transmission. There is a lot of bandwidth and an amazing amount of channels at 2GHz and above.

    To minimize cross traffic in high density areas, they are line of sight. Depending on the antenna, they can be sharply focused at a target or in a broad beam.

    I have seen X-band door openers for low as $20. Surely, these can cheap enough for consumer use.

    For people afraid of microwaves turning people green with colorful cancerous bumps out of your head, just think about the energy level of a 1 watt microwave transmitter that can be used for a computer versus a 100,000 watt radio station transmiter. The telephone company uses microwaves for relay stations, but I doubt they want this to catch on...

  6. Re:UK/Europe on Massive Bandwidth over Powergrids? · · Score: 3

    In the US, most places I have seen have a transformer on every street corner. Its because great savings on wire and current losses can be realized with long skinny wires to a 13,500 volt transformer. A skinny wire to your block and a big, fat cable to your house is cost effective. Transformers have other benefits as well, like absorbing much of direct lightning hits.

  7. Light dimmer friendly? on Massive Bandwidth over Powergrids? · · Score: 2

    Not only would shielding be a problem, but what about the sharp spikes created by light dimmers? Those SCR's turn full on anywhere in the 60 Hz cycle (they are great noise machines for AM radios.)

    At work, we have hundreds of motor controllers up to 500,000 watts that make an oscilloscope on the mains light up due to noise (and that's after the snubbers AND isolation transformers.) So, there might be a problem with communications in many places...

  8. Typical press release on Massive Bandwidth over Powergrids? · · Score: 5

    Promise the world and watch that stock price jump. +4.44 points? Look at some the claims:

    ... the company has said individual consumers could get network connections of 2.5 gigabits per second--an estimate the company calls highly conservative ... But even at that speed, one could download the entire contents of an average computer's hard drive in a second

    2.5 Gigabit is a long ways away from a 6.5 gigabyte hard drive.

    Anyhow, I suppose you could have a high bandwidth transmission over the power lines, even without the high frequencies. Just imagine the transmission as a current loop with the current modulated at extreme levels. Unfortunately, the cost considerations to do this seem very interesting.

  9. Re:Conductivity. on CPU Cooling Insanity · · Score: 2

    I may work in unusual conditions as I have seen anything catch fire. Perhaps mineral oil is very safe as a coolant.

    I wonder what the flashpoint of mineral oil is. I use synthetic oil in my car due to it having a significantly higher flashpoint. I tried to burn Mobil-1 with a propane torch once. An oil that needs at least 75 more degrees to burn is less likely to break down and do evil things.

    I must just see extreme conditions. Put it in a demanding application where it cools a poor electrical connection at 5 amps from a 150,000 volt load and it can explode in a colorful fireball. Water will do the same thing too if the hydrogen is allowed to accumulate.

  10. More than one way to make diamonds on CPU Cooling Insanity · · Score: 2

    Another way to make diamonds is using an acyteline cutting torch and cut a slab of iron. I believe it was someone at a steel manufacturing plant where it was discovered that the slag edge where the sheet was cut was hard enough to instanty dull a large bandsaw blade. The story I hear is that they had an engineer check it out and found the floor where the cutting was done had a layer of very fine diamonds in the soot. Unfortunately, a process could not be made to sort through it cheaply.

    What this means is that it is unwise to take a bandsaw or drill next to slag.

  11. Where to get surplus cases on CPU Cooling Insanity · · Score: 2

    Another place to consider getting iron cases for surplus would be an electric motor rebuilding company. They are in most cities. They have all the other essentials, such as transformer oil, epoxies, enamel, insulating standoffs, etc... You might even be able to pick up one of those iron boxes with the cooling fins on the side from the scrap iron bin. They would look cool and sure to dissipate all that extra heat your CPU can manage.

    Who knows, you might be able to fit the air conditioner in the same box and seal the whole contraption. Some of the boxes have jacks on the outside for instrument hookups allready there! Many possibilities! (Be the first on your block to have a computer that is fireproof, armor plated bullet proof, resistant to nuclear blasts, and EMP!)

  12. Re:Silent cooling on CPU Cooling Insanity · · Score: 3

    I was thinking about what you can dip a 10,000 rpm drive or a whole computer in: enamel. Our 400 horsepower DC motors that see 600 volts have the windings protected in this way. Enamel is flexible, tough, protective, and is insulates against electricity, yet it can transfer heat quite well. Its durable and can take abuse. I have seen DC motors under high voltage work in wet conditions without fail.

  13. Re:And change the wipers while you're at it... on CPU Cooling Insanity · · Score: 2

    Actually, this is done with TIG welders. Many TIG welders have a seperate coolant supply you hook up in addition to the main welding power supply. The welding "cable" is actually a set of skinny plastic tubes that run distilled water over the wire. Without the circulating water, the cable burns in a shower of blue flame. I had the opportunity to replace a few of these cables when the operator failed to check the coolant level.

  14. Re:Not just low conductivity. on CPU Cooling Insanity · · Score: 3

    Yes, we have a water cooled 500Kwatt tube at work in a 400KHz induction welder. It is powered by 8,000 volts DC and we use distilled water to cool it.

    It has quite a protection circuit too, just in case something goes wrong. Since the tube is not much larger than a kitchen blender, an interruption in the water coolant might be unforgiving. There are dozens of flow rate sensors that make sure the water keeps it cool.

    The output of the tube is fed into a transformer that is actually copper tubing with flowing distilled water. The final output is the induction coil, or just a few wraps of water cooled copper tubing.

    It has analog and digital computers to make adjustments and proper welds. Quite a fun machine. You would not want to ever wear a wedding ring or have your car keys on you if you walk up close to it. It will turn anything metal close to the coil white hot in a second.

  15. Fun with mineral oil on CPU Cooling Insanity · · Score: 2

    I enjoyed reading the comments about people afraid placing thier dream machine in oil. We get to play with high voltage and mineral oil at work. In a high voltage test chamber where we can crank the probe up to 150,000 volts at 5 amps, we make place the connections in large, clear lexan (plexiglass) cylinders filled with mineral oil. The oil bath is a nice insulator and helps keep the joint cool, which is important.

    I have heard a story where the joint was poor and not enough oil was in the container (at another location, not where I work!) When another object was under test, the container of the poor connection exploded in a HUGE fireball and the explosion viewed through a window. That must be the reason why high voltage rooms are made of many layers of metal.

    Mineral oil is a great conductor of heat. It flows and moves heat away from the source.

  16. Re:Another Idea on CPU Cooling Insanity · · Score: 3

    Thermal expansion is a real problem in the real world. If you ever had a television that you had to hit the side of it to make it work or clear the picture, you could be facing an expensive (but very easy) repair. Televisions and power supplies usually have areas on circuit boards that get very hot. When they see many power on/off cycles, the expansion tends to cause the soldered joints to crack and become loose. If the loose connection is a conduit for large currents, the resistance will make it even hotter and boil the solder away from the joint. Several years ago, 50% of all television repairs had this problem (I used to fix them!)

    I have seen a $450 repair bill for repairing a projection television where a few joints needed soldering. Your repair bill may be calculated with this equation: worth/2 and the justification is "repaired or replaced high voltage power supply." When you can repair ten of these in a day, it is a lucrative business. Nowdays, most devices that have high current areas are better engineered with rivets and extra solder in critical areas.

  17. Re:How about diamond? on CPU Cooling Insanity · · Score: 3

    Coating whole circuit boards with diamond might be indeed possible and for less than what you might think. There is a vapor process used for tools where a thin layer of diamond crystal are deposited on the surface over time. Its slow, but there are means to do it. This method may not be ideal for circuit boards yet, it might be ideal for semiconductors when they are manufactured.

  18. Fun with liquid nitrogen on CPU Cooling Insanity · · Score: 4

    Speaking of liquid nitrogen making things brittle and shatter, once I was in a chemistry lab late one night when an evil cockroach happend to skitter across the floor. Well, we scooped the bugger up and let him join the fun in our flask of liquid nitrogen.

    Yup, he was instantly converted into a deep sleep. Then, we tossed the baby and his bathwater onto the floor in those pretty balls of steam as liquid nitrogen is famous for. The cockroach landed in two peices. He eventually woke up and couldn't find his feet!

    Has anyone ever tried to run an electronic circuit in temperatures that cold? I suspect the doped regions of transistors would behave differently and have different gain characterstics. I'm not sure a computer would compute.

  19. Re:Mineral Oil? on CPU Cooling Insanity · · Score: 2

    At the bottom of an aquarium? Clear epoxy. Some types of outdoor and industrial transformers are filled with epoxy and sand as a filler. They are impervious to water and dissipate heat well. Get it by the can!

  20. Re:Mercury!!!!!!!!!!! weeeeeee! on CPU Cooling Insanity · · Score: 2

    Mercury is used in some high current relays. If you want an industrial relay where the contacts just don't wear out under a heavy hammering, its the way to go.

    The only problem is when they retire, they have to be disposed of in a sealed rubber lined steel drum approved by the EPA. It has been said that one drop of mercury can destroy a whole lake for things like fishing.

  21. Re:Not just low conductivity. on CPU Cooling Insanity · · Score: 2

    Last year, I made a discovery at the paint section in a closeout store. Among the paint cans was a case of "Flux and circuit board cleaner" and it caught my eye. The ingredients listed trichlorotrifluorethane (freon!) and methylene chloride. At 88 cents per can, I got the case. The had no idea what they were selling!

    The stuff does wonders for cleaning boards in ultrasonic cleaners. Its magic!

  22. Re:Conductivity. on CPU Cooling Insanity · · Score: 3

    The only problem with the power supply in the oil is that if on of the parts, such as a capacitor decides to self destruct, it could spray oil and sparks into the air. Not likely, but not fun to think about either. If you work with oil where there is potential for high releases of energy, an iron case would be ideal to contain any mishaps. Lets say I would not leave this unattended in my house and might be comforted by a fire extinguisher that works...

  23. Re:Another Idea on CPU Cooling Insanity · · Score: 2

    No, the oil will not hurt the connections. We use special grease at work to protect high current connections made of aluminum and other metals. It is necessary to prevent oxidation. Oil will not hurt this application, unless it chemically breaks down into basic carbon compounds.

  24. Transformer oil on CPU Cooling Insanity · · Score: 5

    At work we have two types of transformers: open core and oil filled. The oil filled are much smaller and can handle voltages a magnitude higher up to 150,000 volts at a few megawatts 100% of the time due to the circulation and insulating properties of the oil and large heat fins. The open air type transformers a much larger and require natural convection and only see 14,400 volts. The only advantage of the open air might be the large magnetic core to dampen voltage fluctuations.

    Needless to say, the oil filled transformers are sealed to prevent contamination of the oil and prevent oxidation and cumbustion. If they are ever overheated, the oil tends to break down over time, lose its dielectric properties, and eventually short. Some oil filled transformers have large fans on the heatsinks to keep the oil at reasonable temperatures.

    I'm not sure what blend transformer oil is for our applications as we have a contractor repair our damage, but you can get it in 55 gallon drums. I'm sure any other oil, including mineral oil would be just fine in this application (provided moisture does not contaminate the oil over time.)

    I could imagine a much "prettier" setup where the case is made of painted iron, closed, sealed, and painted. Then lower the freon pressure in the air conditioner to allow much lower temperatures when the gas expands inside the coils.

    Then people might think this is cool and not be offended by the "scraps of styrofoam" and parts laying around everywhere. Looks like a prototype to me...

  25. Re:The threat on "Usenet Death Penalty" against AOL · · Score: 3

    > The questions might go like this:
    > 1. Someone posts something that's totally opposite to what you believe. You then:
    > a. Post an intelligent, well thought arguement that adds to the debate.
    > b. Type an angry reply, one sentence long, in all caps.

    I forsee one problem: AOLers aren't *that* stupid. Anyone old enough to know how to send an email/usenet message can also


    Oh? Back in about 1994 when AOL opened the floodgates onto usenet, they gave users a big point and click button. I was told they were given a brochure describing "full usenet access" over a variety of topics. The newsgroup alt.best.of.usenet was the group at the top of the list if I remember right. In less than an hour, it was the worst of usenet with thousands of posts destroying any use that group had. To my horror, I was logged in at the time when this happened.

    Typing in a one sentence reply in all caps would be the best case. Usually, it was a sentence fragment, or just a thought, or a word or two. Not only that, there was a bug with the posting software that duplicated each post seven times. Irresponsible? I would have to say yes. As I see it, AOL is here to exploit the internet. It raped and pillaged the newsgroups in 1994 and I am not surprised that it is extending its reach into our mailboxes.