Maharashtra HSC Electronics and Hardware Technician (NSQF E5) key terms

The relationship stating that current through a conductor equals the voltage across it divided by its resistance, written I = V/R. It lets a technician predict how a circuit behaves when voltage or resistance changes.

The rule that the algebraic sum of all voltage drops and rises around any closed loop of a circuit equals zero. Used to analyse series networks and check measured voltages during fault finding.

Two basic ways of connecting parts. In series, the same current flows through every part and resistances add; in parallel, the same voltage appears across each branch and currents add.

The property of a material that opposes the flow of electric current, measured in ohms. It depends on material, length, cross-sectional area and temperature, and sets how much current a given voltage produces.

DC flows in one direction at a steady value, as from a battery. AC periodically reverses direction, as from mains supply, and is described by its frequency and RMS value.

A standard scheme in which coloured bands on a resistor body encode its value and tolerance. Reading bands in the correct order from the tolerance end lets a technician identify an unmarked or faded part.

The permitted deviation of a component's actual value from its stated nominal value, usually given as a percentage. It tells the technician how much variation is acceptable before a part is considered faulty.

A component that stores electric charge between two conducting plates separated by a dielectric. It blocks steady DC while passing changing signals, and is used for filtering, coupling and timing.

The requirement that an electrolytic capacitor's positive and negative leads be connected the correct way round. Reversing them can cause overheating, leakage or rupture, so the stripe marking the negative lead must be checked.

A two-terminal semiconductor device that conducts readily in one direction and blocks the other. It is used for rectification, reverse-polarity protection and signal clamping in electronic circuits.

A diode designed to operate safely in reverse breakdown at a defined voltage. Connected with correct polarity it holds a steady reference voltage, making it useful for simple voltage regulation and overvoltage clamping.

A three-terminal semiconductor device in which a small base current controls a larger collector current. It is used for amplification and as an electronic switch, and its terminals are emitter, base and collector.

A transistor in which voltage applied to a gate controls current flow between source and drain. It draws almost no gate current, so it suits low-power switching and high-input-impedance circuits.

Setting the steady DC voltages and currents at a transistor's terminals so it works in the intended region, such as active, cut-off or saturation. Incorrect bias is a common cause of distortion or non-switching.

A complete circuit fabricated on a single semiconductor chip and packaged with external pins. ICs range from simple logic gates to microcontrollers, and their pin numbering and orientation must be observed when fitting.

Joining metal surfaces with a filler alloy melted at a temperature below the melting point of the parts. In electronics it forms both an electrical connection and a mechanical bond on a printed circuit board.

A chemical agent that removes oxide from metal surfaces and helps molten solder wet them during soldering. Residue may need cleaning, and some fluxes require fume extraction for health reasons.

A dull, grainy, poorly bonded joint caused by insufficient heat, movement during cooling or contaminated surfaces. It often looks connected but gives intermittent or high-resistance contact and must be reworked.

Removing solder from a joint so a component or wire can be taken off without damaging the board. It uses a solder sucker, desoldering braid or hot-air tool together with adequate heat.

Repairing or replacing a soldered connection or component on an assembled board. Good rework restores the joint to the same quality standard as the original, without lifting pads or overheating parts.

A basic digital circuit that produces a defined output for each combination of binary inputs, such as AND, OR, NOT, NAND and NOR. Gates are combined to build decision and control logic.

A table listing every possible combination of inputs to a logic circuit alongside the resulting output. It is the standard way to specify and verify the behaviour of gates and combinational circuits.

A set of rules for manipulating binary variables using operations such as AND, OR and NOT. It allows logic expressions to be simplified before implementation, reducing the number of gates needed.

A single chip containing a processor, memory and programmable input/output peripherals. It runs a stored program to read sensors, drive outputs and communicate with other devices in embedded systems.

Software permanently stored in a device's non-volatile memory that controls its low-level operation. It may be updated by flashing, and a failed update can leave hardware unresponsive until reprogrammed.

A small program that runs first after power-up and loads or allows updating of the main firmware. It enables recovery from a corrupted application and is often entered by holding a specific button.

A general-purpose instrument that measures voltage, current, resistance and often continuity. Correct range, function and probe placement must be selected before use, especially when measuring current.

An instrument that displays how a signal's voltage varies with time on a screen. It reveals waveform shape, amplitude, frequency and noise, which a multimeter alone cannot show.

A check using a meter's low-resistance mode, often with an audible beep, to confirm an unbroken conductive path. It is used to trace wiring and find open circuits with the power switched off.

Comparing an instrument's readings against a known reference and adjusting it so results stay within stated limits. Valid calibration records support trustworthy measurements and quality audits.

An unintended low-resistance path that lets excessive current bypass the normal load. It can blow fuses, damage components or start a fire, and is located by isolation and continuity testing.

A protective device containing a metal element that melts and opens the circuit when current exceeds its rating. A blown fuse must be replaced with the same rating, never a higher one or a wire link.

A circuit, usually of diodes, that converts alternating current into direct current. It is followed by filtering and often regulation to produce a steady supply for electronic equipment.

A circuit or IC that holds its output voltage steady despite changes in input voltage or load current. Regulators may be linear or switching, and switching types offer higher efficiency.

The practice of controlling charging, discharging and protection of rechargeable cells to keep them safe and extend life. It includes monitoring voltage, current and temperature and preventing overcharge or deep discharge.

Handling rules for lithium cells, which can overheat or ignite if overcharged, shorted, punctured or charged below freezing. Correct chargers, protection circuits and fire-safe storage are essential.

A sudden transfer of static charge between bodies that can destroy or degrade semiconductor devices. It is prevented by wrist straps, grounded mats, proper packaging and controlled humidity.

A work area with grounded wrist strap, dissipative mat, common ground point and no insulating materials near exposed boards. It safely drains static charge from the technician and the work surface.

Conductive or dissipative bags and containers that shield sensitive devices from static charge during storage and transport. Parts should stay inside until needed at a protected workstation.

The practices and protective measures that prevent injury at work, including safe isolation of power, correct tool use, eye and hand protection, and awareness of electrical and chemical hazards.

Removal of soldering and solvent vapours at their source by a fan or filtered extractor. It protects the technician's lungs and eyes from harmful flux and chemical fumes.

A structured list of every component, its reference designator, description and quantity needed to build an assembly. It drives procurement, kitting and verification during production.

A drawing that shows electrical connections between components using standard symbols rather than physical layout. It is the primary reference for understanding and troubleshooting a circuit.

The unique label, such as R12 or C5, given to each component on a schematic and board so it can be identified unambiguously. It links the drawing, the bill of materials and the physical assembly.

A document describing step by step how a specific task must be carried out, including tools, settings and checks. It ensures consistent output and is used in training and audits.

The defined limits or conditions a product or joint must meet to be judged acceptable. Clear criteria let inspectors make consistent decisions and reduce disputes over quality.

A structured method, such as the five-whys or fishbone diagram, for finding the underlying reason a fault occurred rather than only its symptom. It prevents repeat failures and guides corrective action.

The change made to remove the cause of a detected nonconformity so it does not recur. It differs from correction, which only fixes the immediate faulty item.

Passing an unresolved issue to a higher support level with a clear record of symptoms, tests done and customer details. Good escalation avoids repeated questions and shortens resolution time.

A seller's commitment to repair, replace or refund a product within a stated period under specified conditions. Technicians must record serial numbers and fault details to support claims.

Identifying a need and organising resources, risk and effort to deliver a product or service for profit. For technicians it includes costing, pricing, licensing and finding customers.

Working out the true cost of a job, including materials, labour, overheads and wastage, then setting a price that covers cost and earns a margin. Underpricing is a common cause of business failure.

Enrolment under India's Goods and Services Tax system, required once turnover crosses the prescribed threshold or for certain inter-state supplies. It affects invoicing, input credit and record keeping.