very low frequency
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Definition
Noun: * Very Low Frequency (VLF): A band of radio frequencies in the range of 3 to 30 kilohertz (kHz). It is a specific part of the electromagnetic spectrum used for specialized long-range communication.
Usage
- Very Low Frequency is a technical term used primarily in physics, engineering, and telecommunications. It is often abbreviated as VLF.
- It functions as a compound noun, typically used as a singular noun to describe the frequency band itself or as an adjective to describe equipment or signals operating within this range.
Examples
- As a noun (subject/object):
- Submarines use very low frequency for communication because these signals can penetrate seawater.
- The natural phenomenon known as "whistlers" occurs in the very low frequency band.
- As a noun phrase modifying another noun (adjectival use):
- The navy operates a very low frequency transmitter for global communications.
- Scientists are studying very low frequency radio waves from lightning strikes.
Advanced Usage
- "VLF": The standard abbreviation. It is commonly used in technical writing and speech.
- The receiver is tuned to the VLF band.
- The term is often used in contrast with other frequency bands like ELF (Extremely Low Frequency), LF (Low Frequency), and HF (High Frequency).
Variants and Related Words
- VLF: The standard abbreviation for "very low frequency."
- Low frequency (LF): The adjacent, higher frequency band from 30 to 300 kHz.
- Extremely low frequency (ELF): The adjacent, lower frequency band below 3 kHz.
- Radio wave: The type of electromagnetic radiation that includes VLF signals.
Synonyms
- VLF band: A synonymous phrase emphasizing the range of frequencies.
- Myriametric wave: An older, technical term for waves in this frequency range, referring to their very long wavelength (tens of kilometers).
Related Phrases
- VLF communication: Communication systems that utilize the VLF band.
- VLF emission: The act of transmitting or the natural occurrence of VLF radio waves.
Noun
- 3 to 30 kilohertz