Like what you see? Get it in one document for easy printing!
Click Here!
Use coupon code "SAVE50" to get it half price!

Custom Search







Table Of Contents  CertiGuide to A+ (Core Hardware)
 9  Chapter 0100:  Hard Drives
      9  VIII  Physical Characteristics

Previous Topic/Section
Spindle
Previous Page
Pages in Current Topic/Section
1
Next Page
Flying Height
Next Topic/Section

Read/Write Head

Conceptually, the read and write head is very simple. The principal is based on electrical theory seen in Chapter 0001. Specifically, applying electrical current to a coil produces a magnetic field, which alters the magnetic polarity on the magnetic substrate coated on a platter. To read the magnetic polarity, electrical current in the coil is modified when it passes over the magnetic substrate.

Figure 53: Read/Write Heads

 


[spacer]Hand Made Heads

In the early days, the read/write head was turned into a coil by human skilled labor. Specifically, it was done by silk weavers. They had the skills needed work with (by human standards) very small copper to wind the copper around the little V with 'wings', creating the read/write head. The 'wings' helped the head float on an air bearing, much like a kite. The spinning of the platters created the air bearing. Now you know why the insides of a hard drive must be free of contamination.


[spacer]Giant MagnetoResistive (GMR)

IBM
has pioneered new techniques in hard drives. The latest is Giant MagnetoResistive (GMR) heads, named from the giant magnetorestive effect. The effect comes from the fact that by working with different magnetic materials in thin layers, there is a large resistance to change when in a magnetic field. How GMR drives are manufactured is too complex a topic for this book. However if you have wondered how IBM could get a 1 Gig drive about the size of quarter, now you know.



Previous Topic/Section
Spindle
Previous Page
Pages in Current Topic/Section
1
Next Page
Flying Height
Next Topic/Section

If you find CertiGuide.com useful, please consider making a small Paypal donation to help the site, using one of the buttons below. You can also donate a custom amount using the far right button (not less than $1 please, or PayPal gets most/all of your money!) In lieu of a larger donation, you may wish to consider buying an inexpensive PDF equivalent of the CertiGuide to A+ (Core Hardware) from StudyExam4Less.com. (Use coupon code "SAVE50" to save a full 50% off the already low price!) Thanks for your support!
Donate $2
Donate $5
Donate $10
Donate $20
Donate $30
Donate: $



Home - Table Of Contents - Contact Us

CertiGuide to A+ (Core Hardware) (http://www.CertiGuide.com/aplush/) on CertiGuide.com
Version 1.0 - Version Date: December 6, 2004

Adapted with permission from a work created by Tcat Houser.
CertiGuide.com Version Copyright 2004 Charles M. Kozierok. All Rights Reserved.
Not responsible for any loss resulting from the use of this site.