Odisha CHSE +2 Vocational Mobile Technology key terms

A handheld computing device combining cellular radio, a microprocessor, a touchscreen and an operating system that runs installable applications, typically also offering camera, GPS, Wi-Fi and Bluetooth functions.

A single integrated circuit that integrates the application processor, graphics unit, memory controller, modem and other subsystems, reducing board space and power use in modern handsets.

The chip section that handles radio signal processing and protocol layers for cellular communication, separate from the application processor in many designs, and often paired with its own firmware.

An integrated circuit that regulates and distributes battery power to the various sections of a phone, manages charging, and controls sleep and wake states to conserve energy.

A unique 15-digit identifier assigned to a mobile handset at manufacture, used by networks to recognise the device and by technicians to verify model and legal status.

A thin, flat ribbon of conductors with flexible insulation used to connect moving or stacked assemblies such as display, keypad or charging board to the main board.

A zero-insertion-force socket whose latch is lifted before the flex cable is slid in and closed, allowing repeated connection without damaging delicate contacts or ribbon ends.

The primary printed circuit board of a handset carrying the SoC, memory, power section and connectors; also called the logic board or motherboard by technicians.

The small spring-loaded contact block on the main board through which the lithium-ion cell supplies power; a common failure point causing no-boot or intermittent shutdown faults.

A radio system that divides geographic coverage into cells, each served by a base station, so that frequencies can be reused and calls handed over as the user moves.

The fixed radio equipment and antenna installation serving one cell, transmitting to and receiving from handsets and linking them to the rest of the operator network.

A removable smart card holding subscriber identity and authentication keys that the network uses to verify the user and associate the handset with a mobile number.

The process by which an active call or data session is transferred from one cell or base station to another without interruption as the subscriber moves out of coverage.

The measured power level of the received radio signal, usually displayed in bars or decibel-milliwatts, indicating how well the handset is hearing the serving cell.

The conductive structure that converts electrical signals from the transceiver into radiated radio waves and back again; in phones it is often printed on the board or built into the frame.

Voice over Long Term Evolution, a technique that carries voice calls as data packets on a 4G network instead of falling back to older circuit-switched technology.

The configuration entry that tells a handset which gateway and settings to use for mobile data services; wrong APN values are a frequent cause of no-internet complaints.

An open-source Linux-based mobile operating system maintained by Google, used by many manufacturers, with applications distributed mainly through the Play Store.

The low-level program that initialises hardware and loads the operating system kernel; unlocked versions allow technicians to install custom or factory firmware images.

Writing a firmware image onto a handset's storage to restore or update the operating system, often used to recover devices stuck in boot loops or corrupted by failed updates.

A procedure that erases user data and settings and returns the phone to its out-of-box software state, commonly attempted before deeper diagnosis of software faults.

A diagnostic boot state in which third-party applications are disabled, helping a technician determine whether a fault such as freezing or overheating comes from installed software.

A fault in which the handset repeatedly restarts during start-up and never reaches the home screen, usually caused by corrupted firmware, a failing battery or a shorted component.

A test instrument combining voltage, current, resistance and often continuity measurement; the digital type is the standard tool for tracing supply rails on phone boards.

A check performed with a meter's buzzer or low-resistance range to confirm that two points are electrically joined, used to verify tracks, fuses and connector paths.

A bench instrument that provides a regulated, current-limited voltage to power a handset during repair, showing current draw that reveals shorts or excessive consumption.

The sudden transfer of static charge between objects, capable of destroying sensitive integrated circuits; prevented by wrist straps, mats and grounded workstations.

A conductive band worn on the wrist and connected through a resistor to earth, safely bleeding static charge away from the technician before boards are handled.

A drawing showing the electrical connections and component values of a circuit without regard to physical layout, essential for tracing faults on a main board.

An unintended low-resistance path between two points at different potentials, causing excessive current, heat and battery drain; found by current draw and continuity checks.

A solder connection that has not properly fused with the pad or lead, appearing dull and grainy and causing intermittent or open circuits under vibration.

A method in which solder paste is heated until it melts and wets the joints, widely used for surface-mount components and for reworking ball-grid-array chips.

A tool delivering a controlled stream of heated air to melt solder on a localized area, allowing removal and replacement of surface-mount and BGA components.

A chemical agent applied during soldering that removes oxide from metal surfaces and improves wetting, giving brighter, stronger joints and reducing bridging.

A spring-loaded suction tool that draws molten solder away from a joint, used together with an iron to free through-hole components and clear blocked pads.

The process of removing residual solder from a BGA package and fitting fresh solder balls before refitting it to the board, requiring a stencil and precise heating.

The servicing sequence for a liquid-exposed handset: immediate power-off, disassembly, ultrasonic or isopropyl cleaning of the board, drying, and inspection for corrosion before testing.

A bath that uses high-frequency vibration in a suitable solvent to lift corrosion and residue from circuit boards after liquid damage, followed by thorough drying.

A written statement of the diagnosis, proposed repair, parts and price given to the customer for approval before work begins, protecting both parties against later disputes.

A record opened for each handset received, noting customer details, reported fault, accessories, condition and IMEI, and tracking the repair through to delivery.

A seller's or service centre's commitment to repair or replace a product within a stated period and conditions, excluding damage from liquid, impact or unauthorised repair.