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PPhysicsS3 to S5Telecommunication

Telecommunication lab: analogue and digital signals

Every call and message travels as a signal through towers, cables and satellites. Find out how a voice becomes 0s and 1s and why digital wins over noise.

▶ Start the lab🧠 Questions📄 My report
📶64 kbit/s = 8 000 × 8analogue, digital and telecommunication
LevelS3 to S5 (and IGCSE)
TimeAbout 35 min
You useSampling, bits, c = fλ
PriceFree: no account

🎯 Aim

To investigate sampling, digitisation and noise in telecommunication systems.

You will learn to

  • Explain sampling and the minimum sampling rate.
  • Calculate data rates and the number of levels.
  • Compare analogue and digital transmission with noise.
  • Use c = f λ for radio waves.

🧭 What to do

  1. Change the Samples per cycle of the sound and the Bits per sample: compare the samples with the sound.
  2. Add Noise and more links: compare the analogue and digital signals that arrive.
  3. Read the data rate.
  4. Find the smallest number of samples per cycle that still works.
  5. Answer the questions with the class data.
  6. Write your conclusion and download your lab report.

🔬 Lab bench

📋 The data

Telephone voice and radio facts.

🧠 Investigate: answer from the data

Type your answer and tap Check. Use 💡 Hint first; open the method only when you are stuck.

📄 My lab report

Your report collects the aim, your data table, the graphs, your answers and your conclusion. It is made on your phone or computer: nothing is sent to anyone.

Check your conclusion

A sound must be sampled at least twice per cycle of its highest frequency; more bits per sample give more levels and a better copy, but a higher data rate (8 000 × 8 = 64 kbit/s for a phone voice). Noise adds up in analogue signals, but digital signals are regenerated at each tower, so they arrive clean.

➕ Get more from this experiment

📝 Free

Print the worksheet (button above), download the data, and save your report. Teachers can project this page in class.

📦 Premium Lab Pack

1 000 RWF

  • Worksheet: binary codes and a light-signal (torch) communication activity
  • Telecommunication problems
  • Teacher guide and answer key
  • Exam-style questions with marking scheme
See the pack

👩‍🏫 For teachers

Use it as a practical when apparatus is missing, as homework, or as a project. Free lesson plans help you plan, teach and assess.

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