Wales Β· WJECSyllabus
Electronics syllabus, dot point by dot point
Every dot point in the Wales Electronicssyllabus, with a focused answer for each one. Click any dot point for a worked explainer, past exam questions, and links to related dot points. Written by Claude Opus 4.8, Anthropic's latest AI.
Component 1: AC Circuits and Passive Filters
Module overview β- How are AC signals described, and how do capacitors and inductors oppose alternating current through reactance?AC signals and reactance: peak, peak-to-peak and RMS values, frequency and period, capacitive and inductive reactance, and the phase relationship between voltage and current.11 min answer β
- How do RC high-pass and low-pass filters select frequencies, and what sets the cut-off frequency?Passive filters: the RC low-pass and high-pass filter, the cut-off (break) frequency, the frequency response and the half-power point, gain in decibels, and the Bode plot.12 min answer β
Component 2: Audio and Power Systems
Module overview β- How is an audio system built from mixing, filtering, amplification and a power output stage?Audio systems: the audio signal chain, the mixer based on a summing amplifier, tone control with filters, voltage and power amplification, gain in decibels, and driving a loudspeaker.12 min answer β
- How is a steady DC supply produced from the AC mains, and how is it regulated and made safe?Power supplies and mains: the transformer, rectification (half-wave and full-wave bridge), smoothing with a reservoir capacitor, voltage regulation, and electrical safety including fuses and earthing.12 min answer β
Component 1: Communications Systems
Module overview β- How is information sent over a communication system, and why is modulation needed?Communication principles and modulation: the structure of a communication system, the need for a carrier, amplitude and frequency modulation, bandwidth, data rate, and noise and distortion.12 min answer β
- How is information transmitted by radio waves and through optical fibres, and what limits each?Wireless and optical transmission: radio-wave transmission and the aerial, attenuation and noise, optical-fibre transmission, total internal reflection, and multimode versus monomode fibre.12 min answer β
Core Concepts
Module overview β- How do Ohm's law, Kirchhoff's laws and the potential divider let you analyse any DC circuit?DC electrical circuits: charge, current, voltage and resistance, Ohm's law, series and parallel resistors, Kirchhoff's current and voltage laws, the potential divider, and power.12 min answer β
- How do input transducers turn physical quantities into signals, and how do output sub-systems turn signals back into useful effects?Input and output sub-systems: sensors and input transducers (LDR, thermistor, switches) in potential dividers, and output transducers (LED, buzzer, relay, motor) with their driver and interfacing requirements.12 min answer β
- How does the systems approach let you design and analyse an electronic system as a chain of sub-systems?System synthesis: the systems approach, block diagrams, building a system from input, process and output sub-systems, and interfacing between blocks.11 min answer β
Component 1: Instrumentation and Timing Systems
Module overview β- How is a small sensor signal conditioned, amplified and calibrated into a usable measurement?Instrumentation systems: sensors and transducers, the Wheatstone bridge, signal conditioning and amplification, calibration, and the use of the instrumentation amplifier.11 min answer β
- How do astable and monostable timing circuits and oscillators generate and time pulses?Timing circuits and oscillators: RC timing, the monostable and astable using the 555 timer or op-amp, the period and frequency equations, and the production of square waves and clock signals.12 min answer β
Component 1: Logic Systems
Module overview β- How do you design a combinational logic circuit from a specification and simplify it with a Karnaugh map?Combinational logic design: deriving a circuit from a truth table or specification, sum-of-products form, simplification with Karnaugh maps, and building any function from NAND gates only.12 min answer β
- What do the logic gates do, and how does Boolean algebra describe and simplify a logic circuit?Logic gates and Boolean algebra: AND, OR, NOT, NAND, NOR, XOR and XNOR gates, truth tables, Boolean expressions, and the laws of Boolean algebra including De Morgan's theorems.12 min answer β
- How do flip-flops store a bit, and how are they used to build counters and registers?Sequential logic and flip-flops: the difference between combinational and sequential logic, the SR latch, D-type and JK flip-flops, clocking, and using flip-flops to build counters and shift registers.12 min answer β
Component 2: Microcontroller Systems
Module overview β- How is a microcontroller organised, and how are inputs and outputs connected to its ports?Microcontroller architecture and interfacing: the structure of a microcontroller (CPU, memory, ports), digital input and output ports, interfacing switches, sensors and output devices, and the on-chip ADC.12 min answer β
- How is a microcontroller program structured, and how do flowcharts represent decisions, loops and subroutines?Microcontroller programming: flowcharts, sequence, selection and iteration, input and output instructions, time delays, subroutines, and translating a system specification into a program.12 min answer β
Component 1: Operational Amplifiers
Module overview β- How does negative feedback set the gain of inverting and non-inverting op-amp amplifiers?Inverting and non-inverting amplifiers: negative feedback, the virtual earth, the closed-loop gain equations, and the voltage follower (buffer).12 min answer β
- What are the properties of an ideal op-amp, and how does it work as a comparator and Schmitt trigger?Operational amplifier properties and the comparator: the ideal op-amp, open-loop gain, the comparator with and without hysteresis, and the Schmitt trigger.12 min answer β
- How do summing, difference and instrumentation amplifiers combine or compare several signals?Summing, difference and instrumentation amplifiers: the summing (mixer) amplifier, the difference amplifier, and the instrumentation amplifier for small differential signals.12 min answer β
Component 1: Semiconductor Components
Module overview β- How does a p-n junction work, and how do rectifier, Zener, light-emitting and photo diodes behave?Diodes: n-type and p-type material, the p-n junction and depletion layer, forward and reverse bias, the diode I-V characteristic, and the rectifier, Zener, light-emitting and photodiode.12 min answer β
- How does a single-transistor common-emitter amplifier work, and how is it biased to amplify a signal?Transistors as amplifiers: the common-emitter voltage amplifier, biasing for a quiescent point, voltage gain, the role of the load and emitter resistors, and coupling capacitors.12 min answer β
- How do bipolar and MOSFET transistors act as electronic switches, and how do you design a switching stage?Transistors as switches: the bipolar junction transistor and MOSFET, cut-off and saturation, the base (or gate) resistor, switching a load, and the Darlington pair.12 min answer β
Component 1: Signal Conversion
Module overview β- How is an analogue signal turned into digital form, and what sets the quality of the conversion?Analogue-to-digital conversion: sampling, the sampling rate and the Nyquist criterion, quantisation, resolution and the number of bits, and quantisation error.11 min answer β
- How is a digital code turned back into an analogue voltage, and how is the smooth signal recovered?Digital-to-analogue conversion: the summing-amplifier (weighted-resistor) DAC, the R-2R ladder DAC, the output equation, and reconstruction with a low-pass filter.11 min answer β