Learning Academy

CalculatorWiser • Learning Academy

Learn. Practise. Build real understanding.

School subjects, languages, puzzles and practical skills—with worked examples, explanations and guided practice.

27 beginner courses100 lessonsFree starter library
Lesson 1 of 4

AM, FM and tuning

A radio carrier is a rapidly varying signal used to convey information. AM varies amplitude; FM varies frequency. A receiver selects a station and recovers the audio information from its modulation.

An antenna receives many signals. Tuning and filtering improve selection, but interference, signal strength and antenna orientation affect reception. Digital broadcasts use additional methods beyond this introductory model.

SourceSignal pathOutput

Worked example

An AM receiver extracts the audio envelope from a modulated carrier; an FM receiver responds to frequency variations.

Try it yourself

Draw a block diagram: antenna → selection → demodulation → audio amplification → speaker.

Check your understanding

What changes in frequency modulation?

References and further reading

Lessons and examples are original introductory material. These references offer further study; their material is not included as a copied course.

Save this math resource for later
Save to Pinterest