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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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Posted to comp.sys.ibm.pc.hardware.storage,sci.electronics.repair,alt.comp.freeware
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On Sun, 04 Nov 2007 08:43:26 -0800, bluerhinoceros wrote:
Here is the freeware/demoware that PC World suggests at http://www.pcworld.com/video/catid,1...e,1/video.html How to Resurrect a Crashed Hard Drive - PC World Video Electrical recovery for not spinning drives - Connect to a high wattage power supply I don't understand this one. the video implies that the power supply "pushes" the current rather than allowing the device to draw it. I agree with you - this is a wierd suggestion by PC World. But, I can tell you watched the video because that's exactly what it says. PC World seems to imply that a larger capacity power supply INITIAL current/voltage (they call it wattage) surge into the reluctant disk drive could JOLT the dead disk drive into cooperating - sort of like a Taser for reticent hard disks. http://www.pcworld.com/video/catid,1...e,1/video.html Does anyone else know more about this PC World suggestion to resurrect my dead but spinning hard drive - is it science or is it voodoo? |
#2
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Posted to comp.sys.ibm.pc.hardware.storage,sci.electronics.repair,alt.comp.freeware
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Erica Eshoo wrote:
On Sun, 04 Nov 2007 08:43:26 -0800, bluerhinoceros wrote: Here is the freeware/demoware that PC World suggests at http://www.pcworld.com/video/catid,1...e,1/video.html How to Resurrect a Crashed Hard Drive - PC World Video Electrical recovery for not spinning drives - Connect to a high wattage power supply I don't understand this one. the video implies that the power supply "pushes" the current rather than allowing the device to draw it. I agree with you - this is a wierd suggestion by PC World. But, I can tell you watched the video because that's exactly what it says. PC World seems to imply that a larger capacity power supply INITIAL current/voltage (they call it wattage) surge into the reluctant disk drive could JOLT the dead disk drive into cooperating - sort of like a Taser for reticent hard disks. http://www.pcworld.com/video/catid,1...e,1/video.html Does anyone else know more about this PC World suggestion to resurrect my dead but spinning hard drive - is it science or is it voodoo? Urban myth! -- Best Regards: Baron. |
#3
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Posted to comp.sys.ibm.pc.hardware.storage,sci.electronics.repair,alt.comp.freeware
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Erica Eshoo wrote:
On Sun, 04 Nov 2007 08:43:26 -0800, bluerhinoceros wrote: Here is the freeware/demoware that PC World suggests at http://www.pcworld.com/video/catid,1...e,1/video.html How to Resurrect a Crashed Hard Drive - PC World Video Electrical recovery for not spinning drives - Connect to a high wattage power supply I don't understand this one. the video implies that the power supply "pushes" the current rather than allowing the device to draw it. I agree with you - this is a wierd suggestion by PC World. But, I can tell you watched the video because that's exactly what it says. PC World seems to imply that a larger capacity power supply INITIAL current/voltage (they call it wattage) surge into the reluctant disk drive could JOLT the dead disk drive into cooperating - sort of like a Taser for reticent hard disks. http://www.pcworld.com/video/catid,1...e,1/video.html Does anyone else know more about this PC World suggestion to resurrect my dead but spinning hard drive - is it science Its always science. Tho rather mangled in the case of that article. or is it voodoo? Hard drives are immune to that. |
#4
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Posted to comp.sys.ibm.pc.hardware.storage,sci.electronics.repair,alt.comp.freeware
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It seems to me I heard somewhere that Erica Eshoo wrote in article
: On Sun, 04 Nov 2007 08:43:26 -0800, bluerhinoceros wrote: Here is the freeware/demoware that PC World suggests at http://www.pcworld.com/video/catid,1...e,1/video.html How to Resurrect a Crashed Hard Drive - PC World Video Electrical recovery for not spinning drives - Connect to a high wattage power supply I don't understand this one. the video implies that the power supply "pushes" the current rather than allowing the device to draw it. I agree with you - this is a wierd suggestion by PC World. But, I can tell you watched the video because that's exactly what it says. PC World seems to imply that a larger capacity power supply INITIAL current/voltage (they call it wattage) surge into the reluctant disk drive could JOLT the dead disk drive into cooperating - sort of like a Taser for reticent hard disks. Wattage, as everybody here seems to agree, is the actual power consumed by a device; the wattage rating on a power supply is the highest power it's capable of or designed to supply. Amperage is only drawn to the level required by a device; if a device is not defective it will only draw up to its rated amperage and the supply has to be able to meet that demand. Voltage higher than the designed operating voltage of a device may damage or ruin the device. ISTM PC World must be outsourcing its technical writers these days. |
#5
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Posted to comp.sys.ibm.pc.hardware.storage,sci.electronics.repair,alt.comp.freeware
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In comp.sys.ibm.pc.hardware.storage Don Kirkman wrote:
It seems to me I heard somewhere that Erica Eshoo wrote in article : On Sun, 04 Nov 2007 08:43:26 -0800, bluerhinoceros wrote: Here is the freeware/demoware that PC World suggests at http://www.pcworld.com/video/catid,1...e,1/video.html How to Resurrect a Crashed Hard Drive - PC World Video Electrical recovery for not spinning drives - Connect to a high wattage power supply I don't understand this one. the video implies that the power supply "pushes" the current rather than allowing the device to draw it. I agree with you - this is a wierd suggestion by PC World. But, I can tell you watched the video because that's exactly what it says. PC World seems to imply that a larger capacity power supply INITIAL current/voltage (they call it wattage) surge into the reluctant disk drive could JOLT the dead disk drive into cooperating - sort of like a Taser for reticent hard disks. Wattage, as everybody here seems to agree, is the actual power consumed by a device; the wattage rating on a power supply is the highest power it's capable of or designed to supply. Amperage is only drawn to the level required by a device; if a device is not defective it will only draw up to its rated amperage and the supply has to be able to meet that demand. Voltage higher than the designed operating voltage of a device may damage or ruin the device. ISTM PC World must be outsourcing its technical writers these days. Yes. To people that do not have a clue. Arno |
#6
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Posted to comp.sys.ibm.pc.hardware.storage,sci.electronics.repair,alt.comp.freeware
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In comp.sys.ibm.pc.hardware.storage Erica Eshoo wrote:
On Sun, 04 Nov 2007 08:43:26 -0800, bluerhinoceros wrote: Here is the freeware/demoware that PC World suggests at http://www.pcworld.com/video/catid,1...e,1/video.html How to Resurrect a Crashed Hard Drive - PC World Video Electrical recovery for not spinning drives - Connect to a high wattage power supply I don't understand this one. the video implies that the power supply "pushes" the current rather than allowing the device to draw it. I agree with you - this is a wierd suggestion by PC World. But, I can tell you watched the video because that's exactly what it says. This sounds pretty bad, because it is complete nonsense. "Pushing" the current would imply a current source. PC PSUs are voltage sources, i.e. the connected device decides how much current it draws. PC World seems to imply that a larger capacity power supply INITIAL current/voltage (they call it wattage) surge into the reluctant disk drive could JOLT the dead disk drive into cooperating - sort of like a Taser for reticent hard disks. Nonsense. Modern drives do not start up as soon as power is applied. There is at least s slight delay until the voltages have stabilized. It is also possible not so auto-spin, i.e. the drive starts up when it gets a reset signal or a start unit command. http://www.pcworld.com/video/catid,1...e,1/video.html Does anyone else know more about this PC World suggestion to resurrect my dead but spinning hard drive - is it science or is it voodoo? It is voodoo. Might have worked with historic drives 20 years ago and a marginal PSU. Does not work with todays HDD motor controllers. Arno |
#7
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Posted to comp.sys.ibm.pc.hardware.storage,sci.electronics.repair,alt.comp.freeware
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On Nov 4, 1:07 pm, Erica Eshoo wrote:
On Sun, 04 Nov 2007 08:43:26 -0800, bluerhinoceros wrote: Here is the freeware/demoware that PC World suggests at http://www.pcworld.com/video/catid,1...e,1/video.html How to Resurrect a Crashed Hard Drive - PC World Video Electrical recovery for not spinning drives - Connect to a high wattage power supply I don't understand this one. the video implies that the power supply "pushes" the current rather than allowing the device to draw it. I agree with you - this is a wierd suggestion by PC World. But, I can tell you watched the video because that's exactly what it says. PC World seems to imply that a larger capacity power supply INITIAL current/voltage (they call it wattage) surge into the reluctant disk drive could JOLT the dead disk drive into cooperating - sort of like a Taser for reticent hard disks. http://www.pcworld.com/video/catid,1...e,1/video.html Does anyone else know more about this PC World suggestion to resurrect my dead but spinning hard drive - is it science or is it voodoo? I think the key words in the video just prior to the unusual tricks were "Last ditch" and "Slim chance". Rush |
#8
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Posted to comp.sys.ibm.pc.hardware.storage,sci.electronics.repair,alt.comp.freeware
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Erica Eshoo wrote:
On Sun, 04 Nov 2007 08:43:26 -0800, bluerhinoceros wrote: Here is the freeware/demoware that PC World suggests at http://www.pcworld.com/video/catid,1...e,1/video.html How to Resurrect a Crashed Hard Drive - PC World Video Electrical recovery for not spinning drives - Connect to a high wattage power supply I don't understand this one. the video implies that the power supply "pushes" the current rather than allowing the device to draw it. I agree with you - this is a wierd suggestion by PC World. But, I can tell you watched the video because that's exactly what it says. PC World seems to imply that a larger capacity power supply INITIAL current/voltage (they call it wattage) surge into the reluctant disk drive could JOLT the dead disk drive into cooperating - sort of like a Taser for reticent hard disks. http://www.pcworld.com/video/catid,1...e,1/video.html Does anyone else know more about this PC World suggestion to resurrect my dead but spinning hard drive - is it science or is it voodoo? It is science but the advice is abstracted from many electrical engineering disciplines, and couched in laypersons terms. First - DC motor theory: the motor in the drive that spins the disk has whats called 'inrush current'. High inrush occurs because at startup, the motor does not generated enough back EMF to equal the nameplate voltage rating of the motor, and for a few tenths of a second, it (the motor windings) looks close to a short circuit to the power supply. Technically, at the location of a short circuit, the current will go to infinity (or as much as the power supply can deliver) and the voltage will go to zero. The current in the motor windings or fields cutting through a magnetic field is what produces the torque that causes the rotor to spin. Power supply theory: Now, if the power supply that is powering the motor is relatively small (e.g. low wattage), in the startup phase of the motor when the 'short circuit' is present, the power supply may not be capable of supplying the current that is needed by the motor so that it can develop the necessary torque to start rotation. The torque that is developed must overcome the friction caused by the bearings, etc and move the mass on the shaft (armature plus disk)in the motor. Power supplies may have additional circuit protection devices that limit the current, as well as under and over voltage protection. These as well will limit the power (current x voltage) that the power supply can output, thus not allowing the motor to produce the necessary torque to produce rotation. The implication that a power supply 'pushes' power into a device is incorrect, and a laymans attempt at explaining electrical circuit theory. IMHO, it is quite a 'reach' to suggest that getting a larger wattage power supply can fix the problem, although it can work. The same effect could be obtained by taking some of the load OFF of the smaller supply (e.g. disconnect bus loads, DVD/CDs/floppies, etc, or even pull memory out of the MB (leave all but minimum). John |
#9
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Posted to comp.sys.ibm.pc.hardware.storage,sci.electronics.repair,alt.comp.freeware
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In comp.sys.ibm.pc.hardware.storage John Hudak wrote:
Erica Eshoo wrote: On Sun, 04 Nov 2007 08:43:26 -0800, bluerhinoceros wrote: Here is the freeware/demoware that PC World suggests at http://www.pcworld.com/video/catid,1...e,1/video.html How to Resurrect a Crashed Hard Drive - PC World Video Electrical recovery for not spinning drives - Connect to a high wattage power supply I don't understand this one. the video implies that the power supply "pushes" the current rather than allowing the device to draw it. I agree with you - this is a wierd suggestion by PC World. But, I can tell you watched the video because that's exactly what it says. PC World seems to imply that a larger capacity power supply INITIAL current/voltage (they call it wattage) surge into the reluctant disk drive could JOLT the dead disk drive into cooperating - sort of like a Taser for reticent hard disks. http://www.pcworld.com/video/catid,1...e,1/video.html Does anyone else know more about this PC World suggestion to resurrect my dead but spinning hard drive - is it science or is it voodoo? It is science but the advice is abstracted from many electrical engineering disciplines, and couched in laypersons terms. First - DC motor theory: the motor in the drive that spins the disk has whats called 'inrush current'. High inrush occurs because at startup, the motor does not generated enough back EMF to equal the nameplate voltage rating of the motor, and for a few tenths of a second, it (the motor windings) looks close to a short circuit to the power supply. Technically, at the location of a short circuit, the current will go to infinity (or as much as the power supply can deliver) and the voltage will go to zero. The current in the motor windings or fields cutting through a magnetic field is what produces the torque that causes the rotor to spin. Does not aplay, since these motors are not connected to power directly, but through a sphisticated motro controller circuit, that, among other things, limits startup current. Power supply theory: Now, if the power supply that is powering the motor is relatively small (e.g. low wattage), in the startup phase of the motor when the 'short circuit' is present, the power supply may not be capable of supplying the current that is needed by the motor so that it can develop the necessary torque to start rotation. The torque that is developed must overcome the friction caused by the bearings, etc and move the mass on the shaft (armature plus disk)in the motor. Power supplies may have additional circuit protection devices that limit the current, as well as under and over voltage protection. These as well will limit the power (current x voltage) that the power supply can output, thus not allowing the motor to produce the necessary torque to produce rotation. Again, does not apply for a PC PSU, unless it is very close to failing. A HDD draws up to 30W on startup, that should overload no PC PSU. The implication that a power supply 'pushes' power into a device is incorrect, and a laymans attempt at explaining electrical circuit theory. IMHO, it is quite a 'reach' to suggest that getting a larger wattage power supply can fix the problem, although it can work. The same effect could be obtained by taking some of the load OFF of the smaller supply (e.g. disconnect bus loads, DVD/CDs/floppies, etc, or even pull memory out of the MB (leave all but minimum). What is completely missing is that if the PSU is this weak, it is close to death in the first place. Arno |
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