Julio Herrera
NT1110
U3AS1
Videos 1.07, 1.09, and 1.11 are a partial review of topics covered on the A+ certification exam. The A+ exam is a competency test for computer technicians. It is sponsored by the Computing Technology Industry Association (CompTIA), and backed by several major companies in the industry. (4Tests, 2014)
1.07 PORTS AND CONNECTORS
TOPICS
• CONNECTORS
• PORTS
• EXTERNAL DEVICES
• INTERNAL DEVICES
• INTER-CONNECTIONS
TERMS
• SERIAL PORT – male, 9 – 25 pins, transfers 1 bit of data at a time.
• PARALLEL PORT – female, 25 pins, 3 rows, transfers 8 bits of data at a time.
• GAME PORT – female, parallel, 15 pins set up in 2 rows.
• NIC – network interface card. Converts parallel comms from the motherboard system bus to serial comms used by the network cable.
• RJ-45 – Ethernet connector
• MODEM – converts analog phone signals into digital transmissions.
• RJ-11 – phone line connector
• VGA – video graphics array connection port for monitors. 15 pin, D-type, analog connection, replaced by DVI.
• DVI – digital visual interface port.
• S-VIDEO - round connector, 4 or 7 pins, connects to television.
• USB – universal serial bus. USB ports have replaced most parallel ports. They are faster, hot-swappable, and automatically detected and configured.
• SCSI – small computer systems interface. Used to communicate with peripheral hardware (printers, external drives, etc.). Mainly found in server farms. Most PC’s now use USB. (Rouse)
• IEEE 1394/FIREWIRE – used for streaming media. Expected to replace SCSI. Fast, hot-swappable, serial.
• MULTI-MEDIA – includes ports for external I/O devices such as microphones, earphones, speakers. Color-coded.
• PS/2 TECHNOLOGY – 3rd generation IBM multi-media connections. (Fisher)
1.09 VIDEO
TOPICS
• DIFFERENCE BETWEEN CRT AND LCD
• RESOLUTION
• VIDEO CONNECTIONS
• TROUBLESHOOTING
• SAFETY
TERMS
• CRT – cathode ray tube.
• LCD – liquid crystal display
• TFT – thin film transistor, AKA active matrix. Used by LCD displays. Backlighting through polarized panels.
• REFRESH RATE – times per second a CRT beam writes to the screen. The faster the beam writes, the higher the refresh rate, the better.
• RESPONSE TIME – the time needed for an LCD to create a new screen. The less time it takes the lower the response time, the better.
• INTERLACING CRT – a CRT beam that writes to alternating lines during each refresh cycle. This compensates for lower refresh rates.
• CONTRAST RATIO – a ratio of the purest white to the purest black.
• DOT PITCH – in a CRT, the distance between phosphorescent dots that form an image.
• PIXEL PITCH – the addressable pixels on a screen.
• RESOLUTION – same as pixel pitch; the addressable points on a screen.
• NATIVE RESOLUTION – the fixed resolution of a LCD.
1.11 PRINTERS – HARDWARE AND CONFIGURATION
TOPICS
• TYPES OF PRINTERS
• CONNECTIONS
• CONFIGURATION
• TROUBLESHOOTING
TERMS
• IMPACT – describes clusters of pins striking an inked ribbon.
• DOT MATRIX – used to print multi-part forms, uses a tractor feed system, is slow and noisy, paper often jams.
• INKJET - 2 types. Special wax-coated paper keeps ink from smearing. Uses a 4-color system, CYMB (cyan, yellow, magenta, black). o THERMAL BUBBLE – uses heat to force ink through a nozzle. o PIEZOELECTRIC – uses an electrical charge to force ink through a nozzle.
• LASER – uses an electrophotographic, 6-step process. o CLEANING – cleans ink off drum, leaves drum with neutral charge. o CONDITIONING – applies -600V to drum. o WRITING – applies image to drum. The image is -100V, making the image more positively charged than the drum. o DEVELOPING – transfers toner to image. The toner will be more positively charged than the drum but more negatively charged than the image, allowing for transfer. o TRANSFERRING – +600V charge is applied to the paper so that the more negatively charged image will be attracted to it. o FUSING – heat and pressure from rollers melt toner onto page.
• SPOOLING – Sends job to printer and stores job in memory. Printer can function while the OS continues to run, so that the user doesn’t have to wait for the print job to complete.
• QUEUE- list of print jobs waiting to be completed.
• 36 PIN CENTRONIC – device connector.
• 25 PIN PARALLEL – computer connector.
• 802.11, IrDA, BLUETOOTH – wireless connections.
The main thing that I took from these presentations is the A+ information. I wasn’t aware of what kind of certification or licensing I would need later on. I am grateful for this because helps me to put things into a better perspective. The other important thing that I took note of were the troubleshooting instructions. The only thing that is confusing is the sheer volume of information that my brain is trying to process. I think that with repetition, that won’t be an issue any longer.
Works Cited
(2014). Retrieved 10 09, 2014, from 4Tests: http://www.4tests.com/core
Fisher, T. (n.d.). about technology. Retrieved 10 09, 2014, from about.com: http://pcsupport.about.com/od/termsp/g/ps-2.htm
Pearson Learning Solutions Media Player. (n.d.). Retrieved from http://media.pearsoncmg.com/pcp/itt_media/1256386782/index.html
Rouse, M. (n.d.). Retrieved 10 09, 2014, from TechTarget: http://searchstorage.techtarget.com/definition/SCSI 