Class: Senior Secondary School 1 (SS1 / SSS 1)
Term: First Term
Week: 12
Age: 15 years
Duration: 45 minutes
Subject: Radio, Tv & Electronics
Curriculum Theme: Trade
Previous Lesson: Electronic Hand Tools: Types And Identification.
Topic: ELECTRONIC HAND TOOLS
Subject Matter: Uses of hand tools, Soldering, Desoldering, Component removal

Specific Objectives

By the end of the lesson, pupils should be able to:

Cognitive Domain:

Define electronic hand tools.
List various electronic hand tools.
State the uses of common electronic hand tools.
Explain the process of soldering.
Explain the process of desoldering.

Affective Domain:

Appreciate the importance of using the correct tools for electronic work.
Observe safety precautions while using electronic hand tools.

Psychomotor Domain:

Demonstrate the correct use of a soldering iron.
Perform basic soldering techniques.
Perform desoldering using a desoldering pump.
Successfully remove a component from a printed circuit board (PCB).

Collaborate with peers during practical electronic tasks.

Reference Materials

The following resources were used in planning this lesson:

9 Years Basic Education Curriculum for Basic Technology (Senior Secondary School).
State Unified Scheme of Work for Radio, TV & Electronics (SSS 1).
Basic Electronics for Senior Secondary Schools.

Instructional Materials

The teacher will teach this lesson with the aid of:

Soldering iron and stand
Solder wire
Desoldering pump
Printed circuit board (PCB) with components
Wire cutters
Long nose pliers
Screwdrivers
Multimeter
Safety goggles

Rationale for the Lesson

Understanding electronic hand tools helps pupils perform basic repairs and assembly of electronic circuits. This knowledge is important for developing practical skills in electronics and for future careers in technical fields, enabling them to work safely and effectively with electronic devices.

Prerequisite/Previous Knowledge

Pupils should have basic knowledge of common electronic components and their functions.

Lesson Content/Board Summary

ELECTRONIC HAND TOOLS

Definition of Electronic Hand Tools

Electronic hand tools are instruments used to assemble, repair, test, and maintain electronic circuits and devices.

Common Electronic Hand Tools and Their Uses

The following are common electronic hand tools and their uses:

Soldering Iron: Used to heat solder and join electronic components onto a printed circuit board (PCB).
Desoldering Pump (Solder Sucker): Used to remove molten solder from a joint, allowing components to be removed.
Wire Cutter (Diagonal Pliers): Used for cutting wires and trimming component leads.
Long Nose Pliers: Used for holding, bending, and manipulating wires and small components in tight spaces.
Screwdrivers (Flathead and Phillips): Used for fastening and unfastening screws in electronic enclosures and equipment.
Tweezers: Used for handling very small electronic components.
Multimeter: Used for measuring electrical quantities such as voltage, current, and resistance.
Wire Stripper: Used for removing insulation from wires without damaging the conductor.

Soldering

Soldering is the process of joining two or more metal items together by melting and flowing a filler metal (solder) into the joint. The solder has a lower melting point than the base metal.

The basic steps for soldering are:

Clean the component leads and PCB pads.
Heat both the component lead and the PCB pad with the soldering iron.
Apply solder to the heated joint, not directly to the iron.
Remove the solder once sufficient flow is achieved.
Remove the soldering iron.
Allow the joint to cool and solidify without disturbance.

Safety precautions for soldering include ensuring good ventilation, wearing safety goggles, and avoiding direct contact with the hot soldering iron tip.

Desoldering

Desoldering is the process of removing solder from a joint, usually to enable the removal of an electronic component or to correct a soldering error.

The common method for desoldering using a desoldering pump involves:

Heat the solder joint with the soldering iron until the solder melts.
Place the nozzle of the desoldering pump over the molten solder.
Activate the pump to suck away the molten solder.
Repeat if necessary until most of the solder is removed.

Component Removal

Removing a component involves desoldering its connections and carefully extracting it from the PCB.

The steps for component removal typically include:

Desolder all pins or leads of the component using a desoldering pump or wick.
Gently pull the component from the board once all solder joints are clear.
Clean any remaining solder from the PCB holes using the desoldering pump or a small drill bit.

Teaching Methods/Instructional Techniques

Discussion, Lecture, Demonstration, Question and Answer, Visual Aids

Instructional Procedures

Step 1: Introduction

Time: 5 minutes
Teaching Skill: Set Induction
Teacher’s Activity: The teacher greets the pupils, reviews the previous lesson briefly, and then introduces the topic of electronic hand tools by asking pupils what tools they think are used to fix a radio or television. The teacher displays some common hand tools.
Pupils’ Activity: Pupils respond to questions and observe the displayed tools.
Learning Point: Pupils are engaged and aware of the lesson’s relevance to their daily experiences.

Step 2: Definition and Types of Electronic Hand Tools

Time: 8 minutes
Teaching Skill: Explanation/Listing
Teacher’s Activity: The teacher defines electronic hand tools and lists various types, showing examples of each tool where available. The teacher writes key points on the board.
Pupils’ Activity: Pupils listen, observe the tools, and copy notes from the board.
Learning Point: Pupils learn the definition and identify different electronic hand tools.

Step 3: Uses of Electronic Hand Tools

Time: 7 minutes
Teaching Skill: Discussion/Elaboration
Teacher’s Activity: The teacher discusses the specific uses of each listed hand tool, explaining why the correct tool is important for particular tasks. The teacher encourages pupils to share any prior knowledge of tool uses.
Pupils’ Activity: Pupils listen, contribute to the discussion, and ask questions for clarification.
Learning Point: Pupils understand the functions and appropriate applications of various electronic hand tools.

Step 4: Introduction to Soldering

Time: 7 minutes
Teaching Skill: Demonstration/Explanation
Teacher’s Activity: The teacher explains what soldering is and demonstrates the basic steps of soldering using a soldering iron and a simple circuit board. The teacher highlights safety precautions.
Pupils’ Activity: Pupils observe the demonstration carefully and note the steps and safety rules.
Learning Point: Pupils understand the concept and basic procedure of soldering.

Step 5: Desoldering and Component Removal

Time: 7 minutes
Teaching Skill: Demonstration/Explanation
Teacher’s Activity: The teacher explains desoldering and component removal. The teacher then demonstrates how to use a desoldering pump to remove solder and a component from a PCB, emphasising careful handling.
Pupils’ Activity: Pupils pay close attention to the demonstration, observing the techniques for desoldering and component removal.
Learning Point: Pupils learn the techniques for desoldering and safely removing electronic components.

Step 6: Practical Session/Guided Practice

Time: 6 minutes
Teaching Skill: Practical Application/Supervision
Teacher’s Activity: The teacher provides pupils with printed circuit boards, solder, desoldering pumps, and a soldering iron (if available and safe for use in groups). The teacher guides pupils as they attempt to desolder and remove a component from the PCB, offering assistance and correcting techniques.
Pupils’ Activity: Pupils practice desoldering and removing components under the teacher’s supervision.
Learning Point: Pupils gain practical experience in using electronic hand tools for desoldering and component removal.

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

Define electronic hand tools.
List three common electronic hand tools and state their uses.
Explain the process of soldering.
Describe how to remove a component from a PCB using a desoldering pump.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 8: Conclusion

Time: 2 minutes
Teaching Skill: Summarisation
Teacher’s Activity: The teacher summarises the key points of the lesson, reiterating the importance of proper tool use and safety. The teacher assigns homework which includes drawing and labeling three electronic hand tools.
Pupils’ Activity: Pupils listen to the summary and copy the homework.
Learning Point: Pupils consolidate their learning and receive further practice tasks.

Lesson Keywords

Hand tools – Instruments used for manual tasks, in this case, for electronics.
Soldering – The process of joining metals using a filler metal (solder).
Desoldering – The process of removing solder from a joint.
Solder – A fusible metal alloy used to create a permanent electrical and mechanical bond.
Soldering Iron – A tool used for heating solder to join electronic components.
Desoldering Pump – A tool used to suck molten solder from a joint.
PCB – Printed Circuit Board, a board used to mechanically support and electrically connect electronic components.

Differentiation

For pupils who grasp concepts quickly, provide additional complex components on a separate PCB for advanced desoldering practice. For pupils needing more support, offer one-on-one guidance during the practical session and provide simpler components for initial practice, ensuring they master basic soldering and desoldering before moving to more intricate tasks.

Note for teachers using this lesson plan

Teachers should ensure that all safety precautions, especially regarding heat and fumes from soldering, are strictly observed. Adequate ventilation should be provided. Supervise pupils closely during practical sessions to prevent accidents and ensure correct technique. Emphasise the proper care and maintenance of electronic hand tools.