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All the circuits of a computer are made up of various basic electronic components.  These components are the fundamental building blocks of the electrical/ Electronic Circuits.They are generally found on the hard disk drive , motherboard and on in the other parts of a computer and it's peripherals. For a field technician,  it is necessary to identify these components correctly.  The electronic components are embedded on PCBs. A PCB acts as a base for the components that are mounted on its surface and soldered. The components are generally soldered on the circuit board according to a specified design. The circuits are initially built and tested on a breadboard before being embedded in a PCB. Electronic components that may be embedded in a PCB are of two types: • Active  • passive 

Electronics is the branch of science which involves the study of flow and control of electrons (electricity) and their behaviour and effects.  This branch deals with electrical circuits involving active electronic components such as vacuum tubes, transistors,  dishes and integrated circuits and passive electronic components such as resistors, capacitors and inductors, along with interconnection technologies.

MSDSs are available with most of the products which have potential to cause damage to the equipment or some sort of humans while dealing with them. A few examples of these products are: ▪Cleaning solutions such as LCD Cleaner ▪Battery ▪printer cartridge Cleaning solutions such as LCD cleaner, battery, adapter and printer cartridge. MSDS provides information about the safety factors of handling the products and includes their characteristics,  handling strategy, storage instruction and disposal method. It is the responsibility of the technician to read the MSDS sheets which are available with the products . For example , while using a cleaning product to clean the LCD screen of the monitor, if that product is leaving some patches on the screen, it is advisable to read the MSDS sheets prior to using the product.

ESD is the sudden build-up of static electricity when two differently charged objects are brought together. While repairing electronic products, ESD is one of the issues that arises, as it can cause damage to the electronic devices and components. Following are some causes of ESD ▪Unshielded cables and components  ▪improper grounding  ▪Human  negligence  ▪Movement of Air ▪Use of synthetic materials ▪Absence of Electrostatic wrist strap ESD protection is essential for sensitive components during assembly of a device and in the finished device. It can cause severe damage to components such as microchips. Grounding is imperative for RED prevention. An ESD simulator having special output circuit called Human body model (HBM) IS generally utilized to test the vulnerability to electronic devices to ESD from Human contact.

Earthing means connecting the electrical system,  through its non-current carrying conduconductor part, with the ground. The earthing or grounding of a system plays a vital role in maintaining the stability and safety of the system. With poor earthing, electrical systems are prone to damage or accidents.  Following are some purposes of earthing  •Fix the potential of active conductors with respect to earth. •Limit the voltage in electrical system between non-current carrying parts and the earth l. •Remove risk of electric shocks by implementing protection devices. •Limit rise in potential because of medium voltage faults in network with low voltage.  Earthing can be mainly classified as follows: ▪Equipment grounding ▪System grounding  Equipment grounding In this type of earthing system, all the metal parts that are not carrying current are interconnected and then they are connected to the earth.Hence, there is no potential or voltage between : • The metal parts that are not carrying cu

Problems/symptoms Devices not listed in BIOS Action : ▪Ensure that the drive is installed properly. ▪Ensure that the cables are connected properly. Problem/symptoms  No operating system (OS) found or similar message  Action : ▪Ensure that the system is set to boot from the right device.  ▪Ensure that the proper boot order is listed under the boot menu.  ▪Remove any non_bootable dvd from the drive.  ▪Ensure that the boot drive is the first option.  ▪Once boot drive is found, the OS begins to load it.  Problem/symptoms Non_working devices /Device not recognized  Action : ▪Ensure that the cables are plugged in.  ▪Ensure that the cables are firmly connected to the ▪device.  ▪Check that the add_on card are seated in their slots  ▪Check the device drivers.  ▪Try to reinstall the device driver or download the latest version.  ▪Try to uninstall and reinstall the device. Problem/symptoms Problems after installing New software or device driver Action ▪Uninstall the software or driver. ▪Return t

Issue Blank screen (Nothing appears on screen) Diagnosis Improper connection or Display settings Solution ▪ check if the monitor and the CPU power is in ON position. ▪ Check if the monitor is plugged into the CPU ▪ Ensure that the power cable is plugged into the monitor and is not loose. ▪ Some CPUs have multiple ports for display.Check each port by plugging in securely. ▪ When the power button on the monitor is pressed, some status is displayed. This means that the power to the monitor is in ON position and screen display is okay. ▪ check the cable running from the CPU to the monitor. ▪ check the brightness level using the menu button on the monitor . It may have been set to dark. ▪ check that the computer is not in the screensaver or sleep mode. ___________________________________________________ Issue  Computer Doesn't show power Solution ▪  Ensure that the power cable is connected to the CPU and to the monitor. ▪ check the power socket. ▪ Replace the power socket with a differn

Issue  printer error (orange or blinking light) Diagnosis No light in power indicator of printer Solution  ▪ Ensure that the printer is switched on. ▪Reconnect all the printer cables ▪switch off the printer and turn it in again. Diagnosis No Paper or Paper Jam Solution ▪Ensure that the printer has paper. ▪Remove any paper stuck in the roller. ▪Restart the printer ▪Try printing again _______________________________________________ Issue  No Flashing light but cables properly connected Diagnosis  No printer driver Solution  ▪  check the printer driver ▪if needed, update the driver ▪check the connectivity of the printer using the print manager. ▪if the printer is parallel port printer, verify the following settings: ▪Enter the computers CMOS setup. ▪Enable the parallel port. ▪Ensure that the printer is on parallel port mode. ▪Disconnect devices such as scanner or zip drive if they are parallel with the printer to ensure that they are not causing issues with the printer. _________________

A/D Analog-to-Digital ABC Atanasoff Berry Computer ACM Association for Computing Machinery AI Artificial Intelligence ALGOL Algorithic Language ALU Arithmetic Logic Unit AMD Advanced Micro Devices APRANET Advanced Research Project Agency Network ASCII American Standard Code for Information Interchange BASIC Beginners All-purpose Symbolic Instruction Code BCD Binary Coded Decimal BIOS Basic Inpute Output System BIPS Billions of Instructions Per Second BPI Bytes Per Inch CAD Computer Aided Design CAE Computer Aided Engineering CAN Campus Area Network CASE Computer Aided Software Engineering CD Compact Disk CDC Control Data Corporation CD-R CD-Recordable CD-ROM Compact Disk Read Only Memory CD-RW CD Read/Write CL Command Language CLI Command Line Interface COBOL Common Business Oriented CODASYL Conference On Data Systems CPU Central Processing Unit CRT Cathode Ray Tube D/A Digital-to-Analog DAT Digital Audio Tape DBMS Data Base Management System DBS Demand

It is of utmost importance to remove the power while disassembling the computer except while measuring voltages. Removing the power not only includes turning off the power switch but also unplugging it from the socket. Ensure that the power plug should be unplugged to ascertain that there is no power in the computer.  This is required as certain power providers need to provide service to the motherboard even when the power has been switched off. The following two points should be kept in mind while working with power supplies: • Refrain from opening it when it is plugged in. • Even after unplugging,  the capacitors continue to hold, in which case, if the capacitor is touched, it can discharge and give a shock.

As a field technician, there are certain guidelines that must be followed to ensure own safety and that of the co-workers. These guidelines provide a sound, safe and flexible environment to work. Following are some general guidelines to be followed while working with electrical/electronic systems • Follow the correct procedures to ensure zero accidents at work. • obey safety signs, stickers and tags on the equipment/devices • use an appropriate tool for the respective task. • Read labels and instructions given on the components  • wear appropriate clothing and remove metal objects before working. • use prescribed protective safety equipment only. • Follow electrical safety rules when working with electrical machinery/equipment. • Report all unsafe acta or unsafe conditions to the supervisor.

Differnt peripheral devices control differnt things on the monitor. Following are some of the controls of peripheral devices. Mouse It controls the movement of the cursor or pointer on a display screen. Touchpad It is used for pointing(controlling input positioning( on a computer display screen. Scanner It reads text that is printed on paper and translates the information into a form that computer can use. Printer It is used to produce paper(hard copy)output of the text or information that is displayed on the monitor. Speakers It enables a computer to produce the output in the form of various sounds