Radio Waves (HT only)
- Radio waves can be produced by connecting an antenna to a high frequency alternating current (a.c.) power source
- The oscillation of charge in the a.c. circuit produces radio waves with the same frequency of oscillation
- These radio waves produce, or can themselves induce oscillations in electrical circuits
Radio waves are produced by high-frequency alternating currents and induce similar currents when they are received
- In the transmitting antenna:
- The charge from the alternating current oscillates up and down the antenna
- This produces radio waves that can be absorbed by a similar aerial some distance away
- In a receiving aerial:
- The metal aerial absorbs the radio waves
- This creates an alternating current with the same frequency as the transmitted wave
