Delivery – Year 10
At Year 10, students learn about electronic control theory, batteries, circuits, components, meters, semiconductors, capacitors and apply this knowledge to two projects: a simple LED light project and a more complex project designing and making a timer.
For the class Bill produced An Introduction to Electronics, a highly detailed 128-page textbook covering the entire year's work. Extensively illustrated, it includes the knowledge areas covered in classwork, instructions for skill development work and guidelines for the projects, under the following chapter and sub-headings:
- Introduction to Year 10 Electronics
- Electronic Control Theory: Soldering; Dark Detector; Soldering; Electronic Control Software; Input - Process - Output
- Making Electricity - Cells & Batteries: Different types of cells; Magnets, Wires and Motion; Electrostatics; ESD - Electrostatic Discharge
- Circuit Basics: Conductors ; Wire Assignment; Insulators & Semiconductors; Current; Voltage;
- Components: Component Symbols; Resistors; Resistor Prefixes; Resistor Values Exercises; Combining Resistors in Series; Resistors in Parallel; Ohms Law; Power; Kirchoff's Current Law; Kirchoff's Voltage Law; Resistor Combination Circuits
- Multimeters: Multimeter controls; Choosing correct meter settings; Voltage & Current Measurements; Multimeter Safety; Measuring Resistance
- Input Circuits: The Voltage Divider; Dark Detector Input Circuit; Variable Resistors
- Semiconductors: Diodes; Diode Theory; LED's; The Transistor; Transistor Specifications; Transistor Theory
- Capacitance: What Capacitors Do; Time constants; Capacitor Codes and Values; Converting Capacitor Values uF, nF, pF
- Output Circuits
- Three LED Light Project: Student Instructions; Project Planning; Project Timeline; The 3LED Light Circuit; Input Circuit Potentiometers (pots); The Output Circuit; Process/Control Circuit; Eagle Schematic and Layout Editor Tutorial; Component forming; and soldering Codes of Practice LED's and Switches; ; Product Design; 3LED Quality Control
- Timer Project: Student Instructions; Computers and Microcontrollers; What is a Microcontroller; The PICAXE Microcontroller; Power Supplies; PICAXE Software; The BASIC Programming Language; PICAXE on a Breadboard; PICAXE programming cable; PICAXE-08 Development PCB; PICAXE on Veroboard; PICAXE Dev PCB Journal
- Vacuum forming mould making: Vacuum Forming Process;
The Year 10 class learns all about components – how to recognise them, their basic features and how they are represented, says Bill. "Things as such as: transistors have three legs, each one is different, they have to be connected correctly; diodes have two legs but they are different, so they have to be connected correctly; some capacitors are polarised but resistors aren't," explains Bill.
Students also learn about schematic symbols. "In a circuit diagram the symbols don't bear any resemblance to the physical component – a circle with a few lines is a transistor, for example. Students have to pick up this conceptual link. It's exactly like mapping things in cartography – this circle means a man-made feature and this 'x' means a sculpture. The aim is that by Year 11 students are very comfortable looking at a circuit diagram and, by identifying the symbols, will know exactly what the circuit will look like and how it will behave."
Students then learn the theory of putting components together – that an electronic circuit is made up of three things: an input function, a process component for processing electrons in current flow, and an output function. The input function translates a real world property of matter – such as heat or light or displacement – into a flow of electrons or a voltage, that voltage gets processed and converted back into a real world property, such as light or motion.
"We want our Year 10 students to understand that one of the most important input circuits in electronics is the voltage divider.The voltage divider is about as complex as you can get – you've got to understand components and Ohm's law, be able to calculate resistance and current flow, and understand the fundamental concepts of turning a real-world physical property into electronic means. This is very difficult for senior physics students to grasp, and we're asking our Year 10s to do it. And most of them succeed, because in this school we get a lot of bright students – some are already doing Year 11 science in their Year 10 programme."
Once students understand the voltage divider, they are then introduced to the transistor circuit, the op-amp circuit and then, finally, the micro-controller, which, in turn, introduces a new element altogether – software programming. With micro-controllers, there are, again, three functions: the input programme, the processing programme and the output programme. The input programme converts electronic voltages to binary numbers, the processing programme manipulates the numbers and the output programme converts those numbers to a voltage.
"So Year 10 students learn the flow in electronics – where an aspect of the physical world gets translated into a voltage, the voltage gets translated to a number, the number is processed, it gets converted back to a voltage, and then the voltage gets converted to some physical matter property like sound or light. Then they can play with the software. And really that's the whole thing about electronics nowadays – playing with numbers in software. We've got electronic circuits that are just a block of silicon that you can programme to do anything you like. You decide. The micro-processor is the first step in that chain, and it goes on, at university, to more complex devices."
