CIT 141

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CIT 141 PC/Networking Fundamentals

• Lee Weiner
• 572-6025
• weinerl_at_nku.edu

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Course Topics

• Electricity Fundamentals
• How a PC works
• PC Components
• Assembling a PC
• System and Application Software
• Troubleshooting Hardware

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Introduction

• Introduction to Computers and Computer Systems
• Introduction to Networks
• Basic Electricity
• Numbering Systems
• Lab Safety

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Computers Computer Systems

• A computer is hardware
• A Computer System is the combination of hardware
  and software
• System Software
• Application Software

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Three Types of Computers

• Mainframes Large, fast, used by corporations
  and scientific organizations (Thousands of users)
• Minicomputers Medium sized companies and field
  offices (Hundreds of users)
• Personal Computers Small (Single user or small
  group of users)

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Definition of a Network

• Two or more computers connected together to share
  information and resources.
• A network can span a room, a building, a campus,
  or the planet.

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Basic Electricity

• Two types of electric current
• Alternating Current (AC) The kind that comes
  out of the wall
• Direct Current (DC) The kind that comes from a
  battery.
• Most devices need DC, but most power supplied is
  AC.

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Alternating Current

• The 120 volt, 60 Hz current that comes out of the
  wall actually varies from 169 volts to -169 volts
  sixty times a second.
• 120 is the calculated RMS voltage.

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DC Power Supplies

• Power supplies perform two functions
• Transformation Stepping the voltage up or down.
• Rectification Converting AC to DC

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Transformation

• Only AC can be transformed, because the process
  uses the expanding and collapsing magnetic fields
  caused by the increasing and decreasing current.

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Rectification

• AC is rectified using a diode, a device that
  allows current flow in only one direction.

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Filtering

• A capacitor is used to fill in the no-current
  time slots.

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Numbering Systems
Our everyday number system is the decimal system.
(Base 10) Each digit represents a power of 10.
2645
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Numbering Systems
Our everyday number system is the decimal system.
(Base 10) Each digit represents a power of 10.
103 102 101 100
2645
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Numbering Systems
In IT, we sometimes count in two other numbering
systems
Binary Base 2
Hexadecimal Base 16
23 22 21 20
163 162 161 160
1011
3F6A
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Lab Safety

• Use the wrist strap to neutralize ESD
• Remove all jewelry
• Roll up long sleeves (Clothing can hold ESD)
• Use the proper tools for each task
• Handle components by the edge