Read/write heads are very small parts of the hard drive which move on top of the hard disk platter and change the platter's magnetic field into electrical current and electric current into magnetic signals. In essence, then, read/write heads are small electromagnets which perform transition from magnetic to electrical info and back.
The ferrite, metal-in-gap and thin film hard disk heads are the older, traditional hard disk heads. They operate based on the two main guidelines of electro-magnetic force. The 1st principle is utilized in writing to the disk and this is that using an electrical current via the coil will produce a magnetic field. The second principle of electric force is employed when reading back the written information and works opposite to the firstâ€"applying a magnetic field to the coil will create an electrical current.
The more recent kinds of read/write heads are different in the sense that they don't read the induced current in the coil to read back the info. As an alternative they function based mostly on the practise of magnetoresistance, whereby certain materials change their resistance when subject to different magnetic fields.
These more recent MR and GMR heads are also called "dual heads" or "merged heads" because they have separate heads for writing and reading, with each head specializing on a selected function.
The bit size of hard disks is shrinking significantly throughout the years and this means that a particularly great quantity of bits are packed into the disks. This needs the magnetic fields should be made extremely weak so that they don't interfere with each other. This also implies the read/write heads should be correspondingly small and ultra-sensitive to read the weak signals. The new MR and GMR heads are just thatâ€"they are so small and so sensitive.
Modern drive heads float over the outside of the heads and don't physically touch the platter. The older ones made contact and thus were subject to wear and tear. The space between the head and the platter is called the flying height or floating height or the head gap. This distance is indiscernible to the naked eye as it is measured in the millionths of an inch.
Maintaining a certain floating height is critical to definite operation. If the distance is too great, the head cannot read correctly and if it is too near to the platter, there's the chance of a head crash. A head crash may lead to data loss, damages to the head, damages to the platter or all of these 3. This could be due to contamination stuck in the minute opening between the head and the platter, or a shock applied to the disk although it is in operation.
In all but the most serious eventualities, a professional data recovery expert can rescue most, or all, of your data.
The ferrite, metal-in-gap and thin film hard disk heads are the older, traditional hard disk heads. They operate based on the two main guidelines of electro-magnetic force. The 1st principle is utilized in writing to the disk and this is that using an electrical current via the coil will produce a magnetic field. The second principle of electric force is employed when reading back the written information and works opposite to the firstâ€"applying a magnetic field to the coil will create an electrical current.
The more recent kinds of read/write heads are different in the sense that they don't read the induced current in the coil to read back the info. As an alternative they function based mostly on the practise of magnetoresistance, whereby certain materials change their resistance when subject to different magnetic fields.
These more recent MR and GMR heads are also called "dual heads" or "merged heads" because they have separate heads for writing and reading, with each head specializing on a selected function.
The bit size of hard disks is shrinking significantly throughout the years and this means that a particularly great quantity of bits are packed into the disks. This needs the magnetic fields should be made extremely weak so that they don't interfere with each other. This also implies the read/write heads should be correspondingly small and ultra-sensitive to read the weak signals. The new MR and GMR heads are just thatâ€"they are so small and so sensitive.
Modern drive heads float over the outside of the heads and don't physically touch the platter. The older ones made contact and thus were subject to wear and tear. The space between the head and the platter is called the flying height or floating height or the head gap. This distance is indiscernible to the naked eye as it is measured in the millionths of an inch.
Maintaining a certain floating height is critical to definite operation. If the distance is too great, the head cannot read correctly and if it is too near to the platter, there's the chance of a head crash. A head crash may lead to data loss, damages to the head, damages to the platter or all of these 3. This could be due to contamination stuck in the minute opening between the head and the platter, or a shock applied to the disk although it is in operation.
In all but the most serious eventualities, a professional data recovery expert can rescue most, or all, of your data.
About the Author:
Jason Sloan runs a data recovery business called Kingdom Data Recovery Edinburgh who service all the UK. He's got many articles on his web site which refer to issues with storage devices and helpful information about stopping info loss.
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