Beep Codes

The BIOS performs a power on self-test, when the system is turn on. This test is used to ensure that the system is functioning properly and to gather information about that the system contains when a problem is identified with the system during power on-sl-test. The BIOS normally shows an error message. However,in some cases the problem is detected so early in the test that the BIOS cannot even access the video card to print the message, in this case the BIOS will produce a beeping pattern on the speaker to tell about a problem. The exact meaning of the beep codes depends on the type and version of BIOS that you have depending on the BIOS that you are using some BIOS use very simply beep codes in a pattern of verifying number of short beeps. While other may max short and long beeps. However,if you are using a PC made by a company that writes it's own BIOS, you will have to consult your owner's manual or the company's web site or other technical information for assistance. The three most popular type of BIOS are those made by American mega trend's INC, AMI, Award, Phoenix. The Phoenix Bios is famous for it's complicated beep patterns that are actually in up to four groups one or more beeps and then a pause, followed by a many as three more patterns.

Advance Computer and Virus

Computer is an electronic device which can accept the data from user through input device and hold it for sometime to process the data and show to result in a output device.

• F1 to F12-Function key
• A to Z-Alphabet key
• Lab Enter Alt.etc-Operating key
  
• @,#,!,$,%,^,&,etc-Symbol key
• 0 to 9-Numerical key
• Alt65Alt90-A to Z
• Alt95Alt22-a to z
• Alt2 to Alt20-symbol

Virus
(1) Worm virus (which attached with software)
(2) Boot Sector Virus
(3) Micro Virus
(4) Scripted Virus

Some dangerous programmer virus are as follows:
(1) Melisa
(2) DB M
(3) I Love You
(4) I raj on Horse
(5) Happy 99
(6) Nuclear
(7) Concept


Symptoms of Virus Infections:

1. Programs loading and execution take unusually long times.
2. Changes in files and programs size color.
3. Memory and disk spaces are suddenly reduced.
4. Files disappear and strange files may process.
5. Programs may fail to occur.
6. Computer reboots in the middle of the process.
7. Computer hangs on.
8. Disk drives lit on unusually.
   

POLARITY TEST

The voltage induced in secondary winding of transformer either in phase arrangement or a position comparison with primary voltages how the output terminal are consider when the terminal have been (DO).For high voltages and (c,d,a) for low voltage when the voltage induced between d and q in phase with voltage induced between d and q in phase with voltage induced the polarity is said to be subtractive otherwise polarity is addition.
When two corresponding terminals (Dand q) have been interconnected a suitable voltage is connected to one of the winding DO and the voltage assured between other two terminal.Q and q if the voltage connected between the terminals DO. The polarity is subtractive otherwise it is additive.