Having higher voltage DC available in automobiles opens up a LOT of possibilities for fuel savings, as the higher voltage (and consequent lower current/lower I^2R losses) allows all kinds of loads to be operated electrically, rather than directly off of the crankshaft.
The proposed 42 volt standard would allow the intake and exhaust valves to be operated by solenoids, rather than by traditional timing chains, camshafts, lifters, pushrods, and rocker arms, with all their frictional losses. Direct electrical operation of the valves would allow the valve timing to be adjusted "on the fly" to optimize for different load/speed/altitude/fuel, rather than being a fixed function of the camshaft pattern.
Higher voltages also make it possible to run many accessories from their own electric motors, allowing their speed to be controlled as needed, rather than being tied to engine speed. A/C compressors, power steering systems, etc. could all be driven electrically, for increased efficiency.
, not just the ECM (which is already inside a grounded metal box on every car I have seen anyway). The wiring connecting the ECM to the rest of the vehicle will act as an antenna, and carry the incoming pulse right into the ECM.
Completely shielding the entire electrical system of the vehicle would be cost prohibitive, and technically challenging.
than an emergency shutdown. Some highly sensitive military gear is rigged with such devices to facilitate destroying the equipment in the event that a plane crashes behind enemy lines or a base is about to be overrun by enemy forces.
Perhaps the switch the guy pulled was to prevent the computer from falling into VC hands?
The problem GE sets were mostly made from the late '70s to the mid '80s. The problem stemmed from a decision to use double-sided PC boards, but NOT to use plated-through holes to connect the traces between the 2 sides. Instead, GE used what they called "griplets", which were small metal eyelets that passed through the board, and were soldered to the foil on both sides. Unfortunately, with repeated heat/cool cycles, the solder joints would crack due to differential expansion, causing all manner of frustrating intermittent failures. Some of these failures would actually destroy components in the power supply or sweep circuitry, adding to the repair expense.
The standard repair rechnique was to desolder ALL the griplets, and solder in bare wire jumpers between the top and bottom of the board. With maybe 60-70 such connections in the average set, repairing these sets was often more expensive than buying one of the cheap import sets that were just starting to flood the market at the time.
The owner's manual for most pieces of stereo equipment used to have a schematic diagram at the very least, and perhaps a detailed "theory of operation" description and parts list. Nowadays, you don't even get that level of detail in the factory SERVICE manual that you have to pay $40 to get!
At least into the '80s, GE television sets used to have a condensed service manual (schematic and alignment instructions) stashed in a small compartment on the back of the set. Unfortunately, GE sets were some of the least reliable on the market at the time, so that service data was the least the factory could do to apologize for them.:)
About the only products that still seem to include wiring diagrams nowadays are major appliances. Washers and dryers usually have a large diagram pasted inside the back cover.
>I don't know how I'd go about trying to "fix" something where some resistor or cap on the board had gone bad.
Uh, by grabbing a soldering iron and replacing said resistor or cap? Discrete components like that are pretty standardized, and generally dirt cheap.
Now if the failed component is a specialized ASIC or contains proprietary firmware, you might be out of luck if the OEM won't sell you the part you need...
Yes, I was referring to the intensity of the DMT experience compared to that produced by LSD, not the dosage levels of the individual drugs. And the extremely rapid onset of smoked DMT compounds the intensity. You can go from baseline to complete detachment from consensus reality before you can set the pipe down. LSD effects take an hour or 2 to peak, and manifest slowly.
On the issue of drug testing, DMT is normally found (in trace amounts) throughout brain tissue, not just confined to the pineal gland, where it is believed to be produced. I'm not sure if it would be excreted as DMT in the urine, but it is certainly metabolized to something that then gets excreted. The NIDA-5 and all other "drug tests" are actually looking for drug metabolites, not the actual drugs themselves. This would greatly complicate a hypothetical test for DMT, because the breakdown products would be similar if not identical to those of serotonin, a closely related compound.
, being a byproduct of muscle activity in (all?) mammals. As such, it is also present in trace amounts in meat. At one time, you could buy pure GHB powder as a "dietary supplement" in vitamin shops. It is STILL available by prescription under the brand name Xyrem.
ANYONE could fail a drug test that looked for GHB at any time. Same goes for a powerful psychedelic called DMT, which is also a human neurotransmitter. This stuff makes LSD look like a placebo in comparison.
So each and every reader out there is currently in possession of 2 DEA Schedule I controlled substances. You are expected to do your patriotic duty, and turn yourselves in by the end of the day....:)
I live in a world where receiving-type vacuum tubes are only being used in 2 very limited markets, guitar amplifiers and high-end boutique audio equipment.
Neither of these markets is large enough to support even a single tube manufacturer of the scale that was common in the heyday of tubes. Both of these markets seem remarkably resistant to actually developing or employing NEW tube designs, preferring to stick with the 6L6s, 12AX7s, and 300Bs that have been around since WW2 or earlier. The relatively small market that still exists is easily supplied by plants in China and the former Soviet Union, many of which have a reputation for quality that is spotty at best.
The lack of demand and consequent lack of suppliers for the specialized "niche market" materials needed to build quality tubes, along with the physical destruction of most of the specialized production machinery and in-house production information from most of the old line US tube manufacturers makes starting up a new production plant a losing proposition.
At least not if you want tubes that might operate long enough for the computer to actually get through boot sequence.
While tubes are simple in concept, the amount of chemistry, metallurgy, and material science that went into making reliable vacuum tubes was simply astounding. Particularly for applications involving hundreds or thousands of tubes (like computers), achieving very high tube reliability is key to getting the computer to run long enough to actually crank outa few calculations before a tube fails.
Tubes that were designed for computer service needed ultrahigh purity metals, particularly nickel for the cathodes. The level of vacuum needed is FAR higher than you could get with a simple mercury siphon pump (think turbomolecular or oil diffusion pump). Exotic metallurgy and coatings are needed to produce grids and plates that don't emit their own secondary electrons. Cathode coating chemistry was jealously guarded by most manufacturers, and also critical to decent life.
All of this stuff is pretty much a "lost art" these days, and it is likely that nobody will EVER be able to duplicate the quality of the best tubes of the past, as most of the people who did it are now dead. While you can make a triode that will function as an amplifier with rudimentary glassblowing skills, making a tube that will reliably work in a high speed pulse switching environment such as a digital computer takes a great deal more knowledge and infrastructure.
Tube manufacturing was every bit as complicated as semiconductor manufacturing is today.
, probably because a shockingly large percentage of them don't seem to know which end to pick the thing up by.:)
Over ~30 years in electronics, I have met many engineers who are whizzes with SPICE simulations or Fourier transforms, but put them on a bench with a screwdriver and a soldering iron, and you have created a weapon of mass destruction targeted at the most expensive piece of silicon in the vicinity. Some of them know this, and leave the hands-on development/prototyping work to engineering techs, or others with the experience and training for it (most of which is NOT taught in a university EE program anymore).
The few engineers that I have met who can actually BUILD their ideas as well as they could design them got that part of their training outside of an EE program. Some started in TV repair shops, some were techs in the military, and others were ham radio operators, model rocketry geeks, or hardware hackers long before they got out of HS.
The ONLY types of transmissions an amateur station can make are spelled out in 97.111. You will notice that "relaying an internet link when commercial broadband is unavailable" is not among them:
Authorized Transmissions:
(a) An amateur station may transmit the following types of two-way communications:
(1) Transmissions necessary to exchange messages with other stations in the amateur service, except those in any country whose administration has notified the ITU that it objects to such communications. The FCC will issue public notices of current arrangements for international communications;
(2) Transmissions necessary to meet essential communication needs and to facilitate relief actions.
(3) Transmissions necessary to exchange messages with a station in another FCC-regulated service while providing emergency communications;
(4) Transmissions necessary to exchange messages with a United States government station, necessary to providing communications in RACES; and
(5) Transmissions necessary to exchange messages with a station in a service not regulated by the FCC, but authorized by the FCC to communicate with amateur stations. An amateur station may exchange messages with a participating United States military station during an Armed Forces Day Communications Test.
(b) In addition to one-way transmissions specifically authorized elsewhere in this Part, an amateur station may transmit the following types of one-way communications:
(1) Brief transmissions necessary to make adjustments to the station;
(2) Brief transmissions necessary to establishing two-way communications with other stations;
(3) Telecommand;
(4) Transmissions necessary to providing emergency communications;
(5) Transmissions necessary to assisting persons learning, or improving proficiency in, the international Morse code;
(6) Transmissions necessary to disseminate information bulletins;
(7) Transmissions of telemetry.
In addition, if he were to use such a ham/internet setup to conduct ANY business transaction (like order a book from Amazon.com, for example), he would be violating the non-commercial use restrictions of section 97.113.
But in order to get smart people with knowledge of electronics/explosives to do that job, they would have to pay a hell of a lot more than they currently do.
And then you would still have the problem that people who are intelligent and inquisitive quickly become bored with repetitive, mind-numbing work like staring at an endless parade of luggage on an x-ray machine for 8 hours a day. Boredom leads to complacency, exactly what you DON'T want in an explosives screener. People who have the level of knowledge of electronics or explosives that we would think desirable for a luggage screener would probably also be qualified for far more interesting, less repetitive work where they won't have to put up with pissed-off airline passengers all day.
, and I have heard of such setups being used on suicide bombs. The bomber presses down the handheld button, then turns on a second arming switch (hidden). The handheld button has normally closed contacts, so if the bomber lets go for any reason (like being shot/killed), the bomb goes off.
>a terrorist that loads up ten 3oz tubes with whatever he/she would like, replaces the innards of a portable video game with the >things necessary to detonate it, and walks through security without a problem.
>But the latter is a LOT more likely to happen when passing through Security Theater at the airport.
Exactly.
I often wonder what kind of training TSA screeners get that would allow them to distinguish between the x-ray image of a normal consumer electronic device, and one that has a bomb built into it. In the second or 2 that they spend looking at the image, what are they actually looking for? A shadow of an alarm clock and sticks of dynamite?
What would prevent a determined suicide bomber from gutting everything out of a laptop computer that isn't needed to make it boot up (so it would pass the "turn it on for me" inspection they sometimes make you go through). Remove the CD/DVD drive, PCMCIA slot bay, CPU cooler, and most of the batteries, leaving enough empty space to pack with the explosive of your choice and a blasting cap. Neatly done, it would just look like a bunch of electronic parts on an x-ray (kinda like the guts of a laptop do), would pass the power-on test, and could bring a plane down at the touch of a button (like maybe the "sleep" switch?).
Slashdot Mirror
Already been done...
http://carcino.gen.nz/images/index.php/35a796d8/19ccbee0
Having higher voltage DC available in automobiles opens up a LOT of possibilities for fuel savings, as the higher voltage (and consequent lower current/lower I^2R losses) allows all kinds of loads to be operated electrically, rather than directly off of the crankshaft.
The proposed 42 volt standard would allow the intake and exhaust valves to be operated by solenoids, rather than by traditional timing chains, camshafts, lifters, pushrods, and rocker arms, with all their frictional losses. Direct electrical operation of the valves would allow the valve timing to be adjusted "on the fly" to optimize for different load/speed/altitude/fuel, rather than being a fixed function of the camshaft pattern.
Higher voltages also make it possible to run many accessories from their own electric motors, allowing their speed to be controlled as needed, rather than being tied to engine speed. A/C compressors, power steering systems, etc. could all be driven electrically, for increased efficiency.
, not just the ECM (which is already inside a grounded metal box on every car I have seen anyway). The wiring connecting the ECM to the rest of the vehicle will act as an antenna, and carry the incoming pulse right into the ECM.
Completely shielding the entire electrical system of the vehicle would be cost prohibitive, and technically challenging.
at least 1917, well before the "Cold War".
http://en.wikipedia.org/wiki/First_Red_Scare
http://en.wikipedia.org/wiki/Palmer_Raids
http://en.wikipedia.org/wiki/Anti-Communism
Uh, Hiroshima was bombed on August 6th, and Nagasaki was hit on the 9th.
than an emergency shutdown. Some highly sensitive military gear is rigged with such devices to facilitate destroying the equipment in the event that a plane crashes behind enemy lines or a base is about to be overrun by enemy forces.
Perhaps the switch the guy pulled was to prevent the computer from falling into VC hands?
http://web.archive.org/web/20070820040423/http://www.e-sheep.com/Saturnalia/
The problem GE sets were mostly made from the late '70s to the mid '80s. The problem stemmed from a decision to use double-sided PC boards, but NOT to use plated-through holes to connect the traces between the 2 sides. Instead, GE used what they called "griplets", which were small metal eyelets that passed through the board, and were soldered to the foil on both sides. Unfortunately, with repeated heat/cool cycles, the solder joints would crack due to differential expansion, causing all manner of frustrating intermittent failures. Some of these failures would actually destroy components in the power supply or sweep circuitry, adding to the repair expense.
The standard repair rechnique was to desolder ALL the griplets, and solder in bare wire jumpers between the top and bottom of the board. With maybe 60-70 such connections in the average set, repairing these sets was often more expensive than buying one of the cheap import sets that were just starting to flood the market at the time.
Wouldn't you have to somehow be drawing power continuously to run the timer that decides when to draw mains power?
The owner's manual for most pieces of stereo equipment used to have a schematic diagram at the very least, and perhaps a detailed "theory of operation" description and parts list. Nowadays, you don't even get that level of detail in the factory SERVICE manual that you have to pay $40 to get!
:)
At least into the '80s, GE television sets used to have a condensed service manual (schematic and alignment instructions) stashed in a small compartment on the back of the set. Unfortunately, GE sets were some of the least reliable on the market at the time, so that service data was the least the factory could do to apologize for them.
About the only products that still seem to include wiring diagrams nowadays are major appliances. Washers and dryers usually have a large diagram pasted inside the back cover.
>I don't know how I'd go about trying to "fix" something where some resistor or cap on the board had gone bad.
Uh, by grabbing a soldering iron and replacing said resistor or cap? Discrete components like that are pretty standardized, and generally dirt cheap.
Now if the failed component is a specialized ASIC or contains proprietary firmware, you might be out of luck if the OEM won't sell you the part you need...
Yes, I was referring to the intensity of the DMT experience compared to that produced by LSD, not the dosage levels of the individual drugs. And the extremely rapid onset of smoked DMT compounds the intensity. You can go from baseline to complete detachment from consensus reality before you can set the pipe down. LSD effects take an hour or 2 to peak, and manifest slowly.
On the issue of drug testing, DMT is normally found (in trace amounts) throughout brain tissue, not just confined to the pineal gland, where it is believed to be produced. I'm not sure if it would be excreted as DMT in the urine, but it is certainly metabolized to something that then gets excreted. The NIDA-5 and all other "drug tests" are actually looking for drug metabolites, not the actual drugs themselves. This would greatly complicate a hypothetical test for DMT, because the breakdown products would be similar if not identical to those of serotonin, a closely related compound.
, being a byproduct of muscle activity in (all?) mammals. As such, it is also present in trace amounts in meat. At one time, you could buy pure GHB powder as a "dietary supplement" in vitamin shops. It is STILL available by prescription under the brand name Xyrem.
ANYONE could fail a drug test that looked for GHB at any time. Same goes for a powerful psychedelic called DMT, which is also a human neurotransmitter. This stuff makes LSD look like a placebo in comparison.
So each and every reader out there is currently in possession of 2 DEA Schedule I controlled substances. You are expected to do your patriotic duty, and turn yourselves in by the end of the day....:)
I live in a world where receiving-type vacuum tubes are only being used in 2 very limited markets, guitar amplifiers and high-end boutique audio equipment.
Neither of these markets is large enough to support even a single tube manufacturer of the scale that was common in the heyday of tubes. Both of these markets seem remarkably resistant to actually developing or employing NEW tube designs, preferring to stick with the 6L6s, 12AX7s, and 300Bs that have been around since WW2 or earlier. The relatively small market that still exists is easily supplied by plants in China and the former Soviet Union, many of which have a reputation for quality that is spotty at best.
The lack of demand and consequent lack of suppliers for the specialized "niche market" materials needed to build quality tubes, along with the physical destruction of most of the specialized production machinery and in-house production information from most of the old line US tube manufacturers makes starting up a new production plant a losing proposition.
At least not if you want tubes that might operate long enough for the computer to actually get through boot sequence.
While tubes are simple in concept, the amount of chemistry, metallurgy, and material science that went into making reliable vacuum tubes was simply astounding. Particularly for applications involving hundreds or thousands of tubes (like computers), achieving very high tube reliability is key to getting the computer to run long enough to actually crank outa few calculations before a tube fails.
Tubes that were designed for computer service needed ultrahigh purity metals, particularly nickel for the cathodes. The level of vacuum needed is FAR higher than you could get with a simple mercury siphon pump (think turbomolecular or oil diffusion pump). Exotic metallurgy and coatings are needed to produce grids and plates that don't emit their own secondary electrons. Cathode coating chemistry was jealously guarded by most manufacturers, and also critical to decent life.
All of this stuff is pretty much a "lost art" these days, and it is likely that nobody will EVER be able to duplicate the quality of the best tubes of the past, as most of the people who did it are now dead. While you can make a triode that will function as an amplifier with rudimentary glassblowing skills, making a tube that will reliably work in a high speed pulse switching environment such as a digital computer takes a great deal more knowledge and infrastructure.
Tube manufacturing was every bit as complicated as semiconductor manufacturing is today.
Which similarly never killed anyone, although some of the more famous stations DID broadcast from ships in international waters...
, probably because a shockingly large percentage of them don't seem to know which end to pick the thing up by. :)
Over ~30 years in electronics, I have met many engineers who are whizzes with SPICE simulations or Fourier transforms, but put them on a bench with a screwdriver and a soldering iron, and you have created a weapon of mass destruction targeted at the most expensive piece of silicon in the vicinity. Some of them know this, and leave the hands-on development/prototyping work to engineering techs, or others with the experience and training for it (most of which is NOT taught in a university EE program anymore).
The few engineers that I have met who can actually BUILD their ideas as well as they could design them got that part of their training outside of an EE program. Some started in TV repair shops, some were techs in the military, and others were ham radio operators, model rocketry geeks, or hardware hackers long before they got out of HS.
http://hilldill.bigcartel.com/
Just in case you wanted a dildo with Hillary's face on it.
>>250g of calcium chloride,
>that's a box of blackboard chalk..
No, blackboard chalk would be calcium carbonate.
Calcium chloride is the stuff you use to melt ice on your sidewalks in winter....
Sounds like a yeast infection to me. Tell her to get that checked out....
http://yro.slashdot.org/article.pl?sid=07/09/04/2032218
The ONLY types of transmissions an amateur station can make are spelled out in 97.111. You will notice that "relaying an internet link when commercial broadband is unavailable" is not among them:
Authorized Transmissions:
(a) An amateur station may transmit the following types of two-way communications:
(1) Transmissions necessary to exchange messages with other stations in the amateur service, except those in any country whose administration has notified the ITU that it objects to such communications. The FCC will issue public notices of current arrangements for international communications;
(2) Transmissions necessary to meet essential communication needs and to facilitate relief actions.
(3) Transmissions necessary to exchange messages with a station in another FCC-regulated service while providing emergency communications;
(4) Transmissions necessary to exchange messages with a United States government station, necessary to providing communications in RACES; and
(5) Transmissions necessary to exchange messages with a station in a service not regulated by the FCC, but authorized by the FCC to communicate with amateur stations. An amateur station may exchange messages with a participating United States military station during an Armed Forces Day Communications Test.
(b) In addition to one-way transmissions specifically authorized elsewhere in this Part, an amateur station may transmit the following types of one-way communications:
(1) Brief transmissions necessary to make adjustments to the station;
(2) Brief transmissions necessary to establishing two-way communications with other stations;
(3) Telecommand;
(4) Transmissions necessary to providing emergency communications;
(5) Transmissions necessary to assisting persons learning, or improving proficiency in, the international Morse code;
(6) Transmissions necessary to disseminate information bulletins;
(7) Transmissions of telemetry.
In addition, if he were to use such a ham/internet setup to conduct ANY business transaction (like order a book from Amazon.com, for example), he would be violating the non-commercial use restrictions of section 97.113.
But in order to get smart people with knowledge of electronics/explosives to do that job, they would have to pay a hell of a lot more than they currently do.
And then you would still have the problem that people who are intelligent and inquisitive quickly become bored with repetitive, mind-numbing work like staring at an endless parade of luggage on an x-ray machine for 8 hours a day. Boredom leads to complacency, exactly what you DON'T want in an explosives screener. People who have the level of knowledge of electronics or explosives that we would think desirable for a luggage screener would probably also be qualified for far more interesting, less repetitive work where they won't have to put up with pissed-off airline passengers all day.
, and I have heard of such setups being used on suicide bombs. The bomber presses down the handheld button, then turns on a second arming switch (hidden). The handheld button has normally closed contacts, so if the bomber lets go for any reason (like being shot/killed), the bomb goes off.
>a terrorist that loads up ten 3oz tubes with whatever he/she would like, replaces the innards of a portable video game with the >things necessary to detonate it, and walks through security without a problem.
>But the latter is a LOT more likely to happen when passing through Security Theater at the airport.
Exactly.
I often wonder what kind of training TSA screeners get that would allow them to distinguish between the x-ray image of a normal consumer electronic device, and one that has a bomb built into it. In the second or 2 that they spend looking at the image, what are they actually looking for? A shadow of an alarm clock and sticks of dynamite?
What would prevent a determined suicide bomber from gutting everything out of a laptop computer that isn't needed to make it boot up (so it would pass the "turn it on for me" inspection they sometimes make you go through). Remove the CD/DVD drive, PCMCIA slot bay, CPU cooler, and most of the batteries, leaving enough empty space to pack with the explosive of your choice and a blasting cap. Neatly done, it would just look like a bunch of electronic parts on an x-ray (kinda like the guts of a laptop do), would pass the power-on test, and could bring a plane down at the touch of a button (like maybe the "sleep" switch?).