Spinning magnetic storage media or hard drive, disks, HDD, fixed disks, fixed drives as they are also known and referred to have been with us now since their development via IBM labs on September 13th 1956 more than fifty years have passed however the storage capacity has grown significantly more than 50 times!
Classed as on volatile storage unlike RAM random access memory which will lose all data when power is ceased the hard drive will hold the information stored when powered down utilizing the magnetic properties of the disk surface.

Hard disks are comprised of several components, internally there is the platter(s) either a single or multi platter configuration will be arranged based on the total capacity of the media these platters are made from glass, ceramics, or metals, and are covered with a process called spluttering this process is not exact and as such there may be areas of the disk where the coating is ‘uneven’ if the quality is not up to specification then it is rejected.

Platter speeds vary from 4200 RPM revolutions per minute to 15 thousand RPM with the latter faster speeds being employed by SCSI small computer system interface and some newer SATA hard drives the increased speed reduces overhead and increases read and write times as the disk revolution per millisecond are improved considerably.

Video recorders, digital Almost exponential growth of hard disks have created a boom in consumer electronics such as personal cameras, PDA, audio players, and gaming consoles
The user data has to go through many process’s before it is either read or written to and from the surface of the drive in binary format 0 and 1 such systems employed previously are RLL run length code, MFM, PRML partial response maximum likelihood the next level up from the binary is the hexadecimal stage.

Data from the surface is read and written by the head stack assembly HSA via MR magneto resistive and GMR giant magneto resistive head stages which will typically assign one head per surface.
No contact should be made between the platter and HSA in the user data area on some hard drives the heads do park on the surface of the media however most ramp off to the outer diameter of the media if the heads do come into contact with the surface particularly when the platters are spinning serious damage to the surface may occur and data loss experienced this failure type is commonly known as a head crash.

Our labs have researched this failure type which occurs for a number of reasons such as power fluctuations causing the drive to oscillate or effect the rotational winds and fly height of the HSA, bearing issues which create vibration beyond tolerance, and thermal changes to the HSA and disk enclosure.
Control for the HSA is from the VCM voice coil motor which is capable of controlling the position of the heads to within <1 Micron.

A preamplifier is connected to the HSA as the signals from the heads are very weak and need boosting considerably the signal is then sent to the PCB printed circuit board for further processing, encoding and decoding stages.

Thermal calibration bad sector marking and bad sector lists are dealt with by the firmware and on board processor on the PCB and help create the translator for access to the logical and user space geometry of the hard drive this process is continually updated and adjusted to ensure smooth performance of the hard drive.

SMART self monitoring analysis report tool can suggest issues with the media and warn of any imminent danger to the user data areas however it has been observed that this facility may not warn fast enough or to late and many computer system BIOS basic input output systems are not configured for smart.
Magnetic storage does have a finite life cycle which is based on basic physics and the deterioration of the magnetic surfaces of the disk and stop start cycles of the HSA as such all users should keep a backup of the important data.

iPod’s have truly revolutionised the music scene in a similar way that the Sony Walkman did in the 1980’s.
Portable, sleek, cool are just some of the adjectives that describe the iPod and with massive storage storage allows music lovers to store their favourite tunes on mass and be able to listen to them on demand whenever and wherever.

Of course it goes without saying that over the years the music collection investment can be considerable.
its dead or making strange noises or presents you with a sad face icon, then one day you switch on to listen to your music at a time you least expect it the iPod does not respond LCD screen.
What now? All those tracks, songs, time, money, the family and personal pics all lost, but you did back up?
No? well actually most user rarely backup their personal computer hard drive let alone their iPod after all this kind of technology never goes wrong does it?
The actual storage device inside the iPod varies from model to model many utilize the Toshiba range of hard drive media newer NANO models employ solid state technology as this does offer some extra benefits of being more robust and free from the knocks and bumps of daily use of the device.
Opening iPod device for the uninitiated may appear to be daunting and thought must also be given to if the device is still under Apple warranty as opening the device may invalidate your warranty however pitched against this is the cost and time of the actual music data on you iPod is it worth it? In most cases the answer is a resounding YES! most definitely.
If opening the iPod is not for you then you must consider dealing with a data recovery company that has all the tools and experience in dealing with this product and have recovered many other iPods.
Software recovery can be of some help occasionally however for physical issues this will not help and in fact the more that the player is on and attempts made at recovering the data then the chance of recovery diminishes considerably.
The iPod player file system is based on FAT File Allocation Table system FAT32 and Apple proprietary system for the folder and file structure of the tunes to recovery any data you must be able to access the file system from LBA 0 to the end of the LBA logical structure and then be able to copy the data to a reliable media such as a hard drive then you must be mount the cloned data and reconstruct the data based on the above information.
For more information and help or if you require data recovery services to your iPod please contact an engineer where they will be pleased to assist you further.