The communication frequency of the walkie talkie is generally written as wavelength or frequency, for example, 2 meter wave or 150MHz. This table lists the correspondence between the commonly used wavelength and frequency
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Wave Length
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10 Meter
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6 Meter
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5 Meter
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2 Meter
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70 Centimeter
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Frequency
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30 MHz
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50 MHz
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60 MHz
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150 MHz
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440 MHz
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The relationship between wavelength and frequency is that they are inversely proportional, wave velocity = wavelength × Therefore, electromagnetic waves with different frequencies have different wavelengths in the air. the propagation speed of electromagnetic waves with different frequencies (or different wavelengths) is the same. the propagation speed in the air is about 3x10e8 m/s. the higher the frequency of electromagnetic waves, the shorter the corresponding wavelength. the electromagnetic wave having a larger frequency has a shorter wavelength. radio waves have the longest wavelength (lowest frequency), while rays have the shortest wavelength (highest frequency)
Generally, radio waves refer to the peak 30GHz (Giga Hertz) from the extremely low frequency 10KHz to the extremely high frequency. because the radio spectrum beyond this range has very different characteristics, such as light and X-rays. however, the above-mentioned 10KHz to 30GHz is usually divided into seven areas, of which the high frequency 3-30MHz is what we usually call short wave
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VLF, Very Low Frequency, 10KHz - 30KHz
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LF, Low Frequency, 30KHz - 300KHz
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MF, Medium Frequency, 30KHz - 3000KHz
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HF or SW, High Frequency, 3MHz - 30MHz
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VHF, Very High Frequency, 30MHz - 300MHz
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UHF, Ultra High Frequency, 300MHz - 3000MHz
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SHF, Super High Frequency, 3GHz – 30GHz
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