Very high frequency

Definition

Very High Frequency (VHF) refers to the range of electromagnetic waves with frequencies between 30 MHz and 300 MHz. VHF is commonly used in television broadcasting, FM radio, and two-way radios.

5 Must Know Facts For Your Next Test

1. VHF frequencies range from 30 MHz to 300 MHz.
2. VHF waves are used extensively in communication systems such as television and FM radio.
3. Due to their relatively short wavelength, VHF waves can be obstructed by large buildings and terrain features.
4. VHF signals generally have a range of about 100 miles under normal conditions.
5. The ionosphere does not reflect VHF waves well, limiting their long-distance propagation.

Review Questions

• What is the frequency range for Very High Frequency (VHF)?
• Name two common uses of VHF in everyday technology.
• Why do VHF signals have limited long-distance propagation?

Related terms

Frequency Modulation (FM): A method of encoding data on an electromagnetic wave by varying its frequency. FM is widely used for high-fidelity broadcasts of music and speech.

Ionosphere: A layer of Earth's atmosphere that contains a high concentration of ions and free electrons. It plays a crucial role in the propagation of radio waves over long distances.

Wavelength: $\lambda$ (lambda) is the distance between successive crests or troughs of a wave. Wavelength is inversely proportional to frequency: $\lambda = \frac{c}{f}$ where $c$ is the speed of light and $f$ is the frequency.