PRACTICAL ELECTRONICS MASTERCLASS (Mr Bell) 1

Basic Electronic Components These components will be discussed further during the course, also have a look at the posters in the room.

Different types of electronic boards:- Prototype breadboards Breadboards are used to test circuits. Wires and components are simply pushed into the holes to form a completed circuit and power can be applied. One of the main advantages of using a breadboard is that the components are not soldered and if they are positioned incorrectly they can be moved easily to a new position on the board.

Printed Circuit Boards (PCB) A printed circuit board, or PCB, is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non - conductive substrate.

Strip boards (often called Veroboard) Strip board is a widely used type of electronics prototyping board characterized by a 2.5mm regular grid of holes, with wide parallel strips of copper cladding running in one direction all the way across one side of the board. Electricity passes through the copper strips and components and wires are used to cross over and create circuits.

Introduction to soldering equipment Soldering iron Iron holder Transformer power supply Sponge Tinning (cleaning tip) Fume extractor Safety spectacles Third hand ALL NUMBERED FOR EACH PUPIL

Additional working equipment De-soldering tool Lead free solder and dispenser Long nose pliers Wire strippers Screwdriver Magnifying glass Micro drill reamer

First Aid – In case of burns Immediately cool the affected area with cool running water or an ice pack (kept in staff fridge freezer). Remove any rings etc. before any swelling starts. Apply burn treatment gel from burns box (next to computer). Cover with a plaster to prevent infection.

Introduction to practical soldering Soldering is a process in which two or more metal items are joined together by melting and then flowing a filler metal into the joint. The filler metal having a melting point of 230°C. Soldering is used to form a permanent connection between electronic components. The metal to be soldered is heated with a soldering iron (350°C - 370°C) and then solder is melted into the connection.

Preparing the soldering iron:  Place the soldering iron in its stand and plug in. The iron will take a few minutes to reach its operating temperature of about 400°C.  Dampen the sponge in the stand. The best way to do this is to lift it out the stand and hold it under a cold tap for a moment, then squeeze to remove excess water. It should be damp, not dripping wet.  Wait a few minutes for the soldering iron to warm up. You can check if it is ready by trying to melt a little solder on the tip.  Move the extractor next to the work piece being soldered to remove any fumes.  Wipe the tip of the iron on the damp sponge. This will clean the tip.  Melt a little solder on the tip of the iron. This is called 'tinning' and it will help the heat to flow from the iron's tip to the joint.

When the solder is in it’s liquid form run it up the wire to get the ‘volcano shape’