Lecture

Week 23 Lesson Plan Addendum


Printers


Types of Printers

Note : serif = tails on letters sans serif = no tails

Impact

Thermal – such as fax machines some cash registers

Use specially coated paper that changes color when heated

Heated pins on the print head strike paper

Work in a 9 or 24 pin configuration

All characters can be created with 9 points but not clearly

Two passes per line

Impact wears out head and pins will break off

Heads are expensive but can be replaced





Dot Matrix – such as auto parts multi copy printers

Use regular paper

Pinheads are not heated but strike a ribbon to leave character

Uses ribbon that travels across paper

Uses 9 and 24 pin configuration on heads

Most problems with broken pins and fouled ribbon

Requires constant head alignment

Characters are not very clear compared to other printers


Liquid Ink

Shoots tiny droplets of ink onto paper

Similar to dot matrix as print head moves across paper


Bubble Jet

Heats ink to 400degrees Ionizes ink

Paper at -200 volts ink at -100 volts – attraction

64 or 128 nozzles fire ink at paper

Data transferred to x,y coordinates

Each color or shade is assigned a number 8 bits all f’s = black

Software determines which jets to fire

Multiple colors create shading effects

Heating the element causes warm up delay

Ink Jets are the same as bubble jets except they don’t heat ink

Originals had 3 cartridges cyan, magenta, yellow

     Blue     red        yellow

Black was made by combining colors

Better quality than dot matrix but not as good as laser

Tend to smudge the ink on low quality paper

Head moves across paper

Later printers have high resolutions and as many as 3000 jets


Solid Ink printers

Use crayon like wax for ink

Store ink as solid blocks

Heated wax is jetted onto paper

Head does not move

Ink is jetted as paper moves over the head

Disadvantage obviously is time for wax to melt


Pen Printers

Banks of colored pens in a carousel

Head chooses one color pen and prints all areas requiring that color

Then chooses another pen and repeats


Laser printers

Great quality of print


Places toner on electrically charged rotating drum

Deposits toner on paper as paper moves through system at same speed the drum is turning

Six steps of laser operation listed below


1. Cleaning

Cleans drum of residual toner & electrical charge

2. Conditioning

Conditions drum to contain high electrical charge

3. Writing

Laser beam discharges a lower charge to only those places where tone is to go

4. Developing

Toner is placed onto drum where the charge has been reduced

5. Transferring

Strong electrical charge draws toner off drum onto paper; takes place outside the cartridge

6. Fusing

Heat and pressure fuse toner to paper






Installing printers on a network

Most installed printers on local machines

The remote machines store driver copies

Shared device across netbui style network

Network capable printer has own Nic card and IP address

Can use DHCP or hard coded

3 ways to connect

Local printer sharing

Network printer if it has a NIC card

Print Server – needs network software on server to control

NOTE:  Each computer must have drivers


Choose Add a Printer

Choose TCP/IP or IPX as port #

Install drivers and use printers IP address


Windows prints by spooling (Simultaneous Peripheral Operation Online)

Places jobs in a print queue

Prints jobs in order

Prints in background if multitasking capable computer

Screen freezes during print can be reduced by increasing virtual memory


Resolution – more dots per inch = better quality

Dot matrix = 300x200

Inkjets 4800x1200 or more


Troubleshooting

Cleaning

Fuser replacement

Paper Jams

Ink Cartridge replacement

Alignment

Upgrade memory

Test Prints

Dos print (copy lpt1)

Low end pricing are cheaper to replace

High end pricing very costly to own

Manufacturers web sites – source of drivers if lost

Maintain drivers’ files in tool kits

Document in your troubleshooting manual