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A+ Cert

 
 
Robert Woodill
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      01-16-2005
Thinking of taking my A+ certification exams, can anyone recommend the best
study guides to use ?


 
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Steven
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      01-16-2005
I havent long just passed that myself , did you check out the PDF of what
they need you to know on there compa website thing?

Steve

"Robert Woodill" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> Thinking of taking my A+ certification exams, can anyone recommend the
> best
> study guides to use ?
>
>



 
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Old Gringo
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      01-16-2005
Robert Woodill wrote:
> Thinking of taking my A+ certification exams, can anyone recommend the best
> study guides to use ?
>
>

There is a bunch of them out there, take your pick:
http://tinyurl.com/5ax4m

--
Old Gringo George
Magic Weaver Of Life
Enjoy Life And Live It To Its Fullest
Freedom For The World <http://www.nuboy-industries.com/>

 
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Rick Blythin
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      01-16-2005
In article <(E-Mail Removed)>,
"Robert Woodill" <(E-Mail Removed)> wrote:

> Thinking of taking my A+ certification exams, can anyone recommend the best
> study guides to use ?


I took the A+ exams back in 2001, I'm also Network+ certified. For both
exams I used Mike Meyers all-in-one books. Passed A+ in 15 minutes,
Net+ took me about an hour, and scored 94%. But I'd been in the field
for 12 years at that point. Depending on your knowledge you may need
additional prep books. I'd highly recommend Mike's book very well
written.

Best of luck!
Rick
 
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nogeekatall
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      01-16-2005

"Robert Woodill" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> Thinking of taking my A+ certification exams, can anyone recommend the
> best
> study guides to use ?


A+ Certification Core Exam - The Test

The A+ Certification is obtained by taking two exams. The first exam is the
A+ Core exam, which this tutorial covers, and the second exam is the A+
Dos/Windows exam.

The A+ Certification is a general computers, maintenance, repair, and
technical skills exam which is sanctioned by the Comptia.

What is it?

The A+ Core exam is 70 questions. Six of the seventy are customer service
questions and don't count towards your final score. The passing score for
the exam is 66%, you have to answer 2/3 questions correctly.

In preparation for the exam, there are several good books out there that I
recommend. The A+ Certification Exam Guide is one of the most comprehensive
books you can buy for your A+ studying. Also, these books are good
resources: A+ Certification for Dummies, A+ Exam Cram, A+ Practice Tests.

Requirements

The A+ exam can be broken down into several areas to study.

Identify terms and parts of system modules. Examples: System Board, Power
Supply, Processor, Memory, Storage Devices, Monitor, Modem, Boot Process,
BIOS, CMOS.

Identify field replaceable modules. Examples: System Board, Storage Device,
Power Supply, Processor, Memory, Input Devices.

Indentify IRQs, DMAs, and I/O Addresses for installation and configuration.
Examples: Standard IRQ settings, DMAs, modems, floppy drives.

Identify peripheral ports, cables, and connectors. Examples: cable types,
maximum lengths, pin layouts, DB-9, DB-25, RJ-11, BNC, PS/2, RJ-45
Connectors.

Configure IDE devices. Examples: Master/Slave, Max # of devices.

Configure SCSI devices. Examples: Addressing, termination, cabling,
internal, external, jumper settings.

Installation of Peripherals. Examples: video devices, modem, storage
devices.

The questions are multiple choice with 4 answers on each question. The
respondent has to choose the best of the 4, as more than one may fit, the
best answer should be chosen.

You also will experience some "identify parts" questions where there are
pictures and you have to identify a part labelled on the picture.

Study Techniques

My recommendation is to take this entire tutorial, then go back through and
create "flash" cards to test yourself. These flash cards are two sided, one
side with the answer, the other with a question. This way, you can test
yourself on both ends, giving the answer for the question, and stating the
question for the answer.

Next, take a few practice exams. This is the best way to know that you know
what you know.

Ports

Serial Ports

Serial communication is used for modems, mice, and general communication
uses. Serial ports are either 25 pin male, "D" Connector, or a 9 pin male,
"D" Connector. It sends and receives 1 bit of data at one time.

COM Ports

COM1 and COM3 use IRQ4. COM2 and COM4 use IRQ3. Most PCs only have two
external COM ports.

Parallel Ports

Parallel ports are used for printers, scanners, and sometimes drives. It is
a 25 pin female, "D" connector. It sends and receives 8 bit of data at one
time.

External ports send data in an asynchronous fashion.

Keyboards are either DIN-5 or PS/2. PS/2 is a smaller port and is often on
newer computers.

Your mouse is either a 9 pin serial or a PS/2. Again, the PS/2 is smaller
and round, while the 9 pin serial is a D-type connector.

Video

Video is a HDA connector. It is a 15 pin female with 3 rows of pins. (VGA &
SVGA)

Cables & Connectors

Serial Cables

Serial cables communicate between two devices with serial ports. 50 feet is
the maximum length a serial cable should be. A null modem cable is used to
communicate between two devices (such as computers).

SCSI

SCSI cables communicate between a SCSI port and a SCSI device, or between
two SCSI devices. SCSI (Small Computer Systems Interface) is standard on
most Macintoshes and optional on most PCs. SCSI is advantageous over other
ports because of its high speed data rate and its ability to support up to
seven devices (eight devices including the controller card).

Hard drives, tape drives, optical drives, scanners, and CD-ROM drives can
all use the SCSI interface. SCSI uses IDs to specify the device, which are
numbered from 0-7. Most SCSI host adapters have to be set to SCSI ID 7. Most
external SCSI devices use a Centronics 50 or male DB-25 Connectors.

Network Cables

Phone lines (some types of networks) use a jack which resembles a phone
jack, a RJ-11 or RJ-12. Another type of network cable, twisted pair, uses
RJ-45 connectors. This connector resembles a flat phone jack.

Drives

There are three main types of hard drives: IDE, EIDE, and SCSI. The factory
does a low level format on the hard drive prior to sending it out which
organizes the hard drive into tracks and sectors. It is possible for you to
perform a low level format of a drive but highly not recommended.

Before the installation of an operating system, you have to partition and
format (high level format). When you partition a drive, you setup different
virtual drives on the PC. Hard drives can have 3 primary partitions and 1
extended partition. Extended partitions can have up to 23 logical
partitions.

A typical IDE drive supports up to 528 megabytes of storage while an EIDE
drive supports 2 gigabytes and larger partitions. Most of the newer PCs you
will work with will have two hard drive controllers, each supporting two
devices. When you install a second drive on one controller with an existing
drive, the first drive needs to be set to be a Master drive and the second a
Slave drive. This is normally done using jumper settings on the hard drives.

A SCSI Controller will let you expand beyond the limit of 4 drives by
allowing you to have up to seven additional SCSI devices for the controller.
There are three different types of SCSI, SCSI 1, SCSI 2, and SCSI 3, also
referred to as Ultra SCSI. SCSI 1 supports up to 8 devices, 1 of them being
the SCSI Card. SCSI 2, which is the most popular, supports up to 16 devices
and it has a higher transfer speed. If the exam does not specify which SCSI
type you are using, assume it is SCSI 1 and has a maximum of 8 devices.

The SCSI chain must have a terminator at both ends. The SCSI card often has
a built in terminator, and a lot of present day SCSI devices also have a
switchable termination on the drive or device. SCSI drives are also more
expensive than EIDE drives, but have a higher access speed and you can have
access to more devices.

CDROMs

CD-ROM was developed by Sony and Phillips. It has a capacity of 650
megabytes of information and is burned onto a CD-ROM using a laser light.

CDFS (Compact Disk File System) is the type of filing system CD-ROMs use to
store information.

Tape Backup Devices

There are three main types of interfaces for Tape Backup devices: Quarter
Inch Cartage (QIC), SCSI, and LPT (printer port).

Controllers control the flow of data from sending and receiving devices.
They match the speed between the devices and convert data between different
formats.

A DTE device is a computer or printer. A DCE is a device such as a modem. A
terminal sends a Ready To Send signal when it transmits to a DCE device such
as a modem. A modem must have the Carrier Present signal before it is able
to receive. RS232 is the standard for serial communication.

SCSI Controllers

As we learned in the previous lesson, there are several types of SCSI. Here,
we will expand on that topic and show you all types of SCSI. This table
shows the characteristics of the different types of SCSI:

SCSI Type
Bus Width
Data Transfer Rate

SCSI 1
8 bit
5 Megabytes per second

Fast SCSI 2
8 bit
10 MBps

Wide SCSI 2
16 bit
10 MBps

Fast-Wide SCSI 2
16 bit
20 MBps

SCSI 3
16 bit
20 MBps


Generally speaking, the controller should be set at ID number 7. The higher
the setting, the higher the priority. Slower drives should be set with a
higher ID so they can access the bus whenever they need to. Each device has
to have a unique ID. In general, the bootable hard drive is set to an ID of
0 and the CD-ROM to an ID of 3. This is not a requirement, just a
suggestion.

PCMCIA (Personal Computer Memory Card International Association) was
originally designed to help expand memory in handheld computers. It is a
16-bit bus interface type. PCMCIA is often referred to as PC Cards and
supports many different types of devices including modems, Ethernet
interfaces, and hard disks.

There are three types of PC Cards, Type I, Type II, and Type III. Type I
cards are 3.3 mm thick. Type II cards are 5 mm thick and are mostly used for
modems and Ethernet cards. This is the most common type of PC Card in
today's systems. Type III cards are 10.5 mm thick and most often are hard
disk cards.

PCMCIA cards use very little power and can be hot swapped - interchanged
without rebooting your computer.

The computer power supply provides the power for all of the internal
components to function. The power supply converts 110 volt AC into four
voltages, +5 volts DC, -5 volts DC, +12 volts DC, and -12 volts DC (ground).

To remove a power supply and replace it, first, shut off the power and
unplug the computer. Open the case.

Disconnect the power supply connectors from the internal components and
motherboard.

Remove the mounting hardware from the power supply and the case. Remove the
power supply.

To install the new power supply, follow these directions in reverse.

BIOS

The BIOS (Basic Input Output System) is the chip that contains low level
software for configuring the system's capabilities and communicating with
the hardware. The BIOS is usually stored in the ROM and communicates between
the software and the hardware so less conflicts present themselves.

Since the BIOS contains the low level software controlling the computer, you
may need to replace it in earlier PCs if you have to upgrade the hard drive.

Typical BIOS options include automatic detection of IDE drives, Option to
enable/disable the processor/cache, Plug 'N' Play technology, and password
protection.

The BIOS writes it configurations to the CMOS (Complementary Metal-Oxide
Semiconductor). The CMOS is powered by a small battery so it can retain the
settings after the power is turned off. the CMOS is usually not upgradeable.

The CMOS configuration program can usually be started using a key
combination when you start up the computer.

When you enter the CMOS configuration program, you can usually change the
hard disk type, display type, floppy disk type, boot sequence, serial &
parallel configurations, date & time, password, and power management.

The expansion bus allows the computer to be upgraded using different
modules. Expansion buses are made up with copper slots where a circuit board
can plug into it. The motherboard contains a bus clock which controls how
fast information flows to the expansion boards and back.

8-bit

The 8-bit expansion bus operates at a maximum of 4.77 MHz (approximately 5),
has eight interrupts, four DMA Channels, and one large 62 slot card.

ISA Bus

The ISA (Industry Standard Architecture) bus is a 16-bit bus with a card
slightly larger than the 8-bit. The 16-bit cards have an extra piece
extending beyond the 8-bit card length. This bus has 16 interrupts and 8 DMA
channels. ISA also runs at 8 MHz. ISA buses are also backwards compatible,
allowing an 8-bit card to fit into it.

MCA Bus

The MCA (Micro Channel Architecture) bus was a proprietary bus designed by
IBM. It is a 16-bit or 32-bit bus and it's clock speed is 10 MHz. It also
offered software configuration instead of dip switches and jumper settings.

EISA

EISA (Extended ISA) bus borrowed a lot of features from the MCA bus and
expanded on them. It has a 32-bit bus and it has more I/O addresses with no
need for interrupts or DMAs. It also still uses the 8 MHz of the ISA card
bus to allow for backwards compatibility

VESA Local Bus (VL Bus)

The VESA Local Bus is a local bus type, meaning it is a bus that runs at the
same speed as the processor. Typically, its used for video to take advantage
of the high speed of transfer to the processor. It is backwards compatible
with the ISA, but has an extra slot to make it 32-bits.

PCI Bus

PCI (Peripheral Component Interconnect) Bus is the newest and most
advantageous types of all of the buses. It supports both 32-bit and 64-bit
data paths to be compatible with 486 and pentium class processors. PCI is
also processor independent, allowing it to be on Macintosh, PC, and RISC
computers. PCI runs at 33 MHz and has a maximum throughput of 256 megabytes
per second.

PCMCIA

PCMCIA (Personal Computer Memory Card Association) is the last type of bus.
It is mainly used in laptops and other small computers and in some digital
cameras. PCMCIA come in three types, Type I, Type II, and Type III.

Type I cards are 3.3 mm thick. Type II cards are the most common and are 5
mm thick. Type III are mainly used for hard disks and are 10.5 mm thick.

Summary

Below is a chart summarizing the different buses:

Bus Type
Bus Size
Speed (MHz)

8-bit
8-bit
4.77

ISA
16-bit
8 (10 in turbo mode)

MCA
16-bit or 32-bit
10

EISA
32-bit
8

VESA Local
32-bit
Processor Speed

PCI
64-bit
Processor Speed

PCMCIA Card
16-bit
33 MHz






The processor, or CPU (Central Processing Unit) controls and directs all
activities in the computer. The CPU contains millions of transistors. The
CPU is measured by its clock speed in MHz. One megahertz is one million
cycles per second. The first IBM PC CPU, the 8088, ran at 4.77 MHz, today's
PCs can exceed 700 MHz.

With the chip is a math coprocessor which handles floating point
calculations, like algebra and statistics. A math coprocessor, also called
an FPU, handles most of the numeric operations.

Most processors have an internal cache which stores frequently used data and
instructions. Cache is broken up into two classifications, L1 which is the
internal cache and L2 which is the external cache.

Each processor have buses that go along with them. The external bus (system
bus) allows the processor to connect with other devices, such as expansion
cards and slots.

The data bus is used to send and receive data.

The address bus is used to describe memory address locations. Each CPU
handles a different width of each of the different types of buses.

The 8088 chip has a 8-bit data bus and a 20-bit address bus.

The 80286 chip has a 16-bit data bus and a 24-bit address bus.

The 80386SX uses the 80387SX as its coprocessor and has a 32-bit data bus
and a 24-bit address bus.

The 80386DX has a 32-bit data bus and a 32-bit address bus.

The 80486SX uses the 80487SX as its coprocessor and has a 32-bit data bus
and address bus.

The 80486DX has a 32-bit data and address bus.

The 486DX2 has a 32-bit data and adress bus.

The 486DX4 has a 32-bit data and address bus.

The Pentium has a 32-bit data and address bus.

The Pentium Pro has a 64-bit data bus and a 32-bit address bus.

The Pentium Pro II has a 64-bit data and address bus.

The MMX version of these chips is enhanced for multimedia applications and
have several important characteristics. It has 57 instructions for
manipulating video, graphic data, and audio. It also has more built-in cache
on the chip.

The following tables summarize the processor chips and their
characteristics:

CPU
Data Bus (bits)
Address Bus (bits)
Speed (MHz)
Transistors

8088
8
20
4.77
29,000

80286
16
24
8-12
134,000

80386SX
32
24
16-20
275,000

80386DX
32
32
16-33
275,000

80486SX
32
32
16-33
1.185 Million

80486DX
32
32
25-50
1.2 Million

486DX2
32
32
33-66
2 Million

486DX4
32
32
75-100
2.5 Million

Pentium
32
32
60-166
3.3 Million

Pentium Pro
64
32
150-200
5.5 Million

Pentium Pro II
64
64
233-400
7.5 Million


CPUs are mounted in different sockets depending on the size of the chip.
Also, 486 chips and newer usually contain heat sinks, with fans, which fit
on top of the processor chip. The CPU socket information is summarized in
this table:

Socket
Voltage
Pins
Processors
Upgrade

0
3.3
168
486DX
486DX2 / 486DX4

1
3.3
169
486DX, 486SX
486DX2 / 486DX4

2
3.3
238
486DX, 486SX, 486DX2
486DX2/4, Pentium

3
3.3 or 5
237
486DX, 486SX, 486DX2, 486DX4
486DX2 / 486DX4

4
5
273
60/66 MHz Pentium
Pentium

5
3.3
320
Other Pentium
Pentium

6
3.3
235
486DX4
Pentium

7
3.3
321
Other Pentium
Pentium

8
3.3
387
Pentium Pro
Pentium Pro


There are two types of upgrade methods, ZIF (Zero Insertion Force) and LIF
(Low Insertion Force) sockets. ZIF sockets have a mounting bar attached.

The first type of memory is ROM. ROM is Read-Only Memory which is a form of
non-volatile memory, meaning it keeps its information even when there is no
power. It is also read only, so you cannot write to it. It contains the
setup program and POST (Power On Self Test) software.

RAM, or Random Access Memory, is a volatile type of memory which loses its
information when power is not present. RAM is where your software and data
is stored when your computer is on.

SRAM is an older type of memory, it stands for Static Random Access Memory.
It is an older type of RAM and stores information using transistors.

DRAM, or Dynamic Random Access Information, stores information using
capacitors.

PROM, Programmable Read Only Memory, this is a programmable type of ROM. It
cannot be erased or changed once it is recorded.

EPROM, Erasable PROM, data can be erased using a UV light on a special
window on the chip. This chip can be reprogrammed.

EEPROM, Electronically Erased PROM, can be erased using a special electrical
charge. Chips can then be reprogrammed after erased. Most modern day BIOS's
are stored in EEPROM.

VRAM is video RAM and is used on video cards.

Cache memory is memory used to cache CPU instructions. L1 is cache memory
that is located on the CPU, L2 is cache memory outside of the CPU.

DIP, or Dual Inline Package, is an older type of RAM used mainly in older
systems.

RAM

RAM is broken up into DOS memory "sections". The first 640K of memory is
Conventional Memory, which is used to load DOS, run programs, and load
drivers. DOS is loaded in the first 64K of memory.

Above 640K, but below 1024K is Upper Memory, also called Reserved Memory.
640KB - 768KB is Video Ram, 768KB - 960KB is for BIOS and RAM Buffers, and
960KB - 1024KB is Motherboard BIOS.

Above 1024K is Extended memory. High Memory Area (HMA) is the first 64K of
extended memory. Extended memory is mainly used by Windows programs.

Expanded memory is sometimes used by DOS programs and is available up to 32
MB. It is swapped in 16 KB pages (addresses in pages of 16 KB).

In DOS, the MEM.EXE program allows you to determine how memory is being used
by DOS. It has several switches, the important ones are highlighted here: /?
the help switch, /C the classify switch - gives a report of how memory is
used, /D the debug switch - details the first 640KB of memory, /F the free
memory switch, shows all free memory blocks in the first 640KB of memory, /M
(module) the module switch, shows the starting addresses of the data,
program, and how much memory is allocated, and /P the pause switch, displays
the output one page at a time.

To use upper memory, you need to make sure the upper memory device driver,
EMM386.EXE is invoked in CONFIG.SYS and DOS=UMB is there also.

DOS=HIGH loads DOS into HMA.

Device=HIMEM.SYS is the extended memory device driver.

A Parity Error indicates a problem with RAM. Parity is a simple form of
error checking and is used to check RAM



IRQs (Interrupt Request Lines) and DMAs (Direct Memory Addresses) are an
important portion to study as they comprise several questions on the exam.
The best method I found was to make flash cards with each IRQ and what it
belongs to. Here is a chart of the common IRQs and what they belong to:

IRQ
Device

0
Timer

1
Keyboard

2
Wired to IRQ 9

3
COM 2 (COM 4)

4
COM 1 (COM 3)

5
Available (often LPT2, sound cards, or network cards)

6
Floppy Disk Controller

7
LPT1

8
Clock

9
Wired to IRQ 2

10
Unused

11
Unused

12
Mouse Port

13
Coprocessor

14
Hard Disk Controller

15
Unused




In most PCs, there are 8 DMA Channels. In most modern PCs, DMA shouldn't be
used, it just slows it down, but older PCs may use DMA. Channels 4-7 are
usually available, while Channel 0 is used to refresh DRAM, Channel 1 is
used by a hard disk controller or sound card, and Channel 2 is usually the
floppy disk controller.

Another important topic which should be memorized are the common I/O
addresses, this table outlines those:

Address (Hex)
Device

00-0F
DMA Controller

20-21
Interrupt Controller

40-43
Timer

1F0-1F8
Hard Disk Controller

200-20F
Joystick Controller

238-23B
Bus Mouse

278-27F
LPT2

2E8-2EF
COM4 Serial Port

2F8-2FF
COM2 Serial Port

300-30F
Ethernet Card

330-33F
MIDI Port

378-37F
LPT1 Port

3E8-3EF
COM3 Serial Port

3F0-3F7
Floppy Disk Controller

3F8-3FF
COM1 Serial Port




POST (Power On Self Test)

The Power On Self Test, or POST, automatically runs every time you turn on
your computer. It tests several components of your computer:

The Processor - if the test fails on the CPU, the system stops, usually no
error code

ROMs - POST checks the BIOS ROMs, problems usually cause the system to stop
with no error code

DMA Controller - if any problems, the system stops

Interrupt Controller - any problems and the system gives an audible error
message of one long beep, then a short beep, then the system stops

System timing chip - this chip provides timing signals for the bus and
processor, this also gives a long beep and a short beep, then the system
stops

Video Card - if this fails, there is a long beep, then two short beeps, then
the system halts

RAM - an error here generates a 201: Memory Error message on the screen, any
error beginning with 2 is a memory error

Keyboard - an error causes a 301 - Keyboard Failure error message on the
screen, followed by a short beep, system may halt or may continue, some
systems may ask you to press F1 to continue - which makes no sense

Floppy Drives - any problems cause a 601 - Floppy Disk error

Other devices - POST checks the other ports and parts of the computer,
beeps, then continues. It also checks the Master Boot Record (MBR) on the
hard drive, if it cannot find the MBR, it will freeze and not continue
loading, otherwise it hands control over to the MBR (or DOS Boot Record -
DBR - if it is booting from a floppy)

Error codes - the following table summarizes the error codes and what they
mean:

Error Code
Problem Description

1xx
System Board problem

161
CMOS Battery Failure

164
Memory System Size error

2xx
Memory related problem

3xx
Keyboard problem

4xx
Monochrome video problem

5xx
Color video problems

6xx
Floppy Disk problem

17xx
Hard disk problem


Electro-static Discharge

Electro-static Discharge (ESD) can cause damage to electronic components as
you work on them. This will have several questions on the exam. ESD can be
caused by static electricity your body picks up as you move, rub against
your clothing, or can be picked up by things you touch.

While working on your computer, you should always wear an Electro static
discharge wrist strap which grounds you. Also, it is recommended that you do
not wear synthetic clothing, as your body rubs against synthetic clothing,
it can create static electricity. This ESD Wrist Strap should not be worn
while working on monitors though, it has stored voltage which could kill
you.

When you store or ship electronic components, you should send them in
antistatic bags. Antistatic bags do not conduct electricity, and can be
reused.

As a computer service technician, it is very important for you to understand
the basics of networking. Networks allows companies to share information,
applications, printers, and other equipment.

Networks are broken down into two categories, Local Area Networks (LAN) and
Wide Area Networks (WAN). Another type of network that may appear on the
exam is the Metropolitan Area Network (MAN).

At the core of the network is the Server. The Server centralizes the control
of resources, account management, and routes information to all of the
workstations on the network.

Peer-Peer Networks

Peer to Peer networks uses the computers in the network as both workstations
and servers. This type of network does not have centralized authentication,
but relies on each PC to interact with another.

Server Based Networks

Server based networks uses a computer as a server to have a central place
for account management and resource management.

Network Topology

Networks are laid out in many different fashions. It is important to know
the difference between the ways networks can be created.

The first way a network can be created is using the Bus Topology. This
consists of a single cable to run to all of the workstations.

Another way is a Star Topology. Each workstation connecting comes off of a
hub.

A third topology is the Ring type of network. A Ring connects each
workstation to each other forming a ring through which messages pass to
every workstation.

Most networks today are actually a Hybrid, or combination of one or more of
the other types.

Communications

Networks communicate using Protocols. A protocol is simply a method for the
network to communicate.

Ethernet

Ethernet is a network architecture. It has several different flavors, with
the original Ethernet designed with 10base5. The "10" stands for 10
megabytes per second. Base is the Baseband communications is uses. The "5"
stands for a maximum distance of 500 meters to communicate with. Original
Ethernet used coaxial wiring, while newer versions use twisted-pair cabling.

There are several flavors of Ethernet, including 10Base2 (10 Mbps, 200
meters), 10BaseT (10 Mbps, 100 meters, twisted-pair), and 100BaseT (100
Mbps, 100 meter, twisted-pair).

Token-Ring

Token-ring is the foundation for IEEE 802.5 specification networks. It uses
a star, logical ring type of network. All of the workstations are cabled to
a Multistation Access Unit, a MAU. The ring is created using this MAU.

Cabling

There are four main types of network cabling: twisted-pair, coaxial, fiber
optic, wireless.

Twisted-pair is the least expensive and most popular type of network
cabling. It is several pairs of wires twisted around each other in an
insulated covering. It is used a lot in 10BaseT networks.

Coaxial cabling consists of a copper wire surrounded by insulation and a
foil shield. It is often used for 10Base2 cabling.

Fiber optic cabling is designed to transfer data at very high rates and over
large distances. It carries a light pulse through a glass core at speeds of
100 Mbps - 1 Gbps.

Wireless networks consist of several different types of transmission medium.
It can use microwave, radio, infrared light, or lasers.

Network Interface Card

Each workstation on the network has a Network Interface Card (NIC) and
special software to allow it to communicate with the network.

Printers is a large part of the A+ Certification Core Exam and there are
several sections that I guarantee will be on the exam. The most important
part of the laser printer section is the order in which a laser printer
operates, it will be at least one question on the exam.

Laser Printers

Laser printers, also referred to as page printers, receive their information
one page at a time and print using electrostatic charges, toner, and laser
light.

The laser printer has several Field Replaceable Modules, including the Toner
Cartridge, the Laser Scanning Assembly, High Voltage Power Supply, DC Power
Supply, Paper Transport Assembly, Transfer Corona Assembly, Fusing Assembly,
and the Formatter Board.

The EP Toner Cartridge holds the toner which is eventually what is printed
onto the page. Toner is sensitive to the electrostatic charges. The Toner
Cartridge also contains the print drum, charge corona wire, and the cleaning
blade. The print drum is has a photosensitive material on it which holds
static charge when it is not exposed to light. The charge corona wire
charges the drum, while the cleaning blade does exactly what its name
suggests, it cleans the used toner off the drum.

The Laser Scanning Assembly holds the laser which shines its light on
certain parts of the printer drum. The electrical charge is reduced and the
toner attaches itself to the drum where the laser has shined.

The High Voltage Power Supply takes 120 V AC and converts it to higher
voltages for the charge corona wire and transfer corona wire. The DC Power
Supply produces +5 Volt DC, -5 Volt DC, and +24 Volt DC from household
current.

The paper transport assembly moves the paper through the printer. It is a
series of motors and rollers to move the paper.

The Transfer Corona Assembly charges the paper with a positive charge as it
moves through the printer. Once charged, it picks up the toner from the
photosensitive drum.

The Fusing Assembly (also known as the fuser) applies pressure and heat to
the paper to seal the toner particles to the paper. In the process of
fusing, there is a halogen lamp which heats up to about 350 degrees F.

The Formatter Board is the circuit board that controls everything that is
going on in the printer. It formats the information then tells the different
modules to function together to get the printed page across.

Order of Processes

The following is the order of processes that occur in a laser printer. It is
an important part to memorize as there will be questions with this on it:

1. Cleaning
2. Conditioning
3. Writing
4. Developing
5. Transferring
6. Fusing

Cleaning - the EP Drum is cleaned with a rubber blade.

Conditioning - the EP drum is given a negative charge of about -600 Volts by
the primary corona wire

Writing - A laser beam writes to the EP Drum, this laser causes portions of
the drum to become almost positively charged

Developing - Toner is applied to the drum by the particles being transferred
to the areas of positive charge

Transferring - The Transfer Corona wire charges the paper with a positive
charge, the EP drum turns as the paper runs beneath it

Fusing - the paper runs through the Fusing Assembly which is heated to 350
degrees F, the toner is fused onto the paper

Other Notes

The ozone filter should be replaced during maintenance.

Dark spots on paper could indicate loose toner particles, run a few pages
through to clear it up.

The primary corona has the highest negative charge in a printer.

Always check the leading edge of paper when there is a paper jam, it can
indicate what part of the printer is causing the jam.

The drum is photoconductive and loses its charge when light hits it. It is
normally negatively charged during the print process.

The transfer corona can cause the print to be too light.

Dot Matrix Printers

Dot matrix printers are a form of impact printer. The printhead in a dot
matrix printer is a series of pins which form numbers, letters, and graphics
as it passes over the paper. In early dot matrix printers, 9-pin was a
common size of printhead. This was called a draft quality printer. Later
versions, such as the 24-pin printhead, print in near letter quality (NLQ)
print mode.

During preventative maintenance, never lubricate the printhead of the
printer. A tight ribbon could be the cause for flecks and smudges on the
paper. Also, a missing or broken printhead pin could cause incomplete
printing. If the print density is erratic, there can be a problem in the
advancement of the printer ribbon.

Bubblejet (Inkjet) Printers

Inkjet printers spray ink onto the page to form the letters and graphics.
The inkjet printer has an ink cartridge which contains several chambers of
ink. When the ink runs out, you must replace the ink cartridge. It is not
recommended to refill ink cartridges

Video Types

There are several major types of video, Monochrome, EGA/CGA (Enhanced
Graphics Adapter, Color Graphics Adapter), VGA (Video Graphics Adapter),
SuperVGA (Super VGA), and XGA (Extended Graphics Array). Each of these
different types of video support differing numbers of colors and
resolutions.

Video Type
Colors Depth
Resolution

Monochrome
Mono
720 x 350

CGA
4

2
320 x 200

640 x 200

EGA
16
640 x 350

VGA
16

256
640 x 480

320 x 200

SVGA
16

256
1024 x 768

800 x 600

XGA
256

65,536
1024 x 768

800 x 600


Monitors

Monitors have two main characteristics, the dot pitch and the refresh rate.
The dot pitch is described in millimeters (mm) and describes shortest
distance between two dots of the same color. For example, a lot of present
day monitors will have a 0.28 mm dot pitch, anything lower than that (such
as 0.25 mm) is superior, anything larger (such as 0.31 mm) is less quality.

The second way to describe a monitor is in its refresh rate. The refresh
rate (also know as vertical scan frequency) measures how many times per
second the monitor is scanned. VGA has a standard refresh rate of 60 Hertz,
or in other words, refreshes itself 60 times per second. The higher the
number, the more times per second the monitor is being refreshed, which
means less flicker is being perceived.

There are two types of monitors, CRT and LCD. CRT is Cathode Ray Tube and
LCD is Liquid Crystal Display. LCD screens are mainly used in Laptops,
though are appearing in desktop models every day.

The A+ Certification Core exam covers a lot of topics, but with this
tutorial, you should be well prepared for passing the exam.

Also, our A+ Discussion Forum allows you to discuss the exam with fellow
test takers!

Links

Learnthat.com has a resource directory for certifications, free online
courses, training company and other information. A+ Certification has its
own section, check it out for additional web resources to study from.

Practice Exam

Learnthat.com has a 100+ question practice exam to help your study efforts.
Check out the A+ Certification web resource section of our links directory
for additional practice exams.




 
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pb3400c pb3400c is offline
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Join Date: Sep 2011
Posts: 1
 
      09-15-2011
took the A+ practical applications test at Pearson Vue Arlington. The administrator of the test took a phone call during the test that lasted several minuits. and I could not concentrate during that time. then found out there was not enough time to finish the exam. pearson vue did nothing about it. I failed by one or two questions
 
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