Recognize every symbol in the exam figures and explain what a schematic does and does not show.
Syllabus: Circuit diagrams: use of term schematic, basic structure; Schematic symbols of basic components
Compendium articles on the ideas in this lesson, beyond what the exam asks.
Practise the 12 pool questions for this group. Answers are shuffled, and every one comes with a one-line "why".
A schematic is a circuit diagram drawn with standard symbols. It shows what connects to what. It does not show wire length, size or what the parts look like.
RememberSchematic = standard symbols + connections. Nothing about looks or lengths.
Match the symbol to its picture. The long-and-short lines of a battery are stacked plates, a resistor zigzags because it resists, a capacitor is two plates with a gap.
Diodes and LEDs have a triangle pointing the way conventional current flows. An LED adds light arrows leaving. A transistor is three leads meeting a thick bar, usually inside a circle, and has an arrow on the emitter.
Memory hookTriangle with a bar = diode. Add little arrows shining out = LED. Three leads in a circle = transistor.
An arrow through or touching a part makes it variable: a resistor, capacitor or inductor you can adjust.
RememberArrow = adjustable. Zigzag + arrow = variable resistor. Coil + arrow = variable inductor. Plates + arrow = variable capacitor.
Loops mean a coil. Two coils side by side with bars between them is a transformer. A flat-topped triangle on a stem, with a line down its middle, is an antenna.
RememberOne coil = inductor. Two coupled coils = transformer. Triangle on a stem = antenna.