Medium frequency, abbreviated MF, is the band of the radio spectrum spanning 300 kHz to 3 MHz, used for AM broadcasting and certain navigation and communication services.
Medium frequency designates the portion of the radio spectrum from 300 kHz to 3 MHz, sitting between the low frequency and high frequency bands. Signals in this range support familiar services such as AM broadcasting along with some navigation and maritime communication. Their propagation characteristics change between day and night, which influences how these signals travel over distance.
The frequency of a signal shapes the requirements for the cable and components that carry it, including impedance and loss characteristics. Whether a system operates in the medium frequency band or elsewhere, matching coaxial and signal cable to the intended frequency helps preserve signal strength and quality from the source to the equipment that uses it.
In commercial and industrial communication, band designations like medium frequency provide a shared framework for specifying transmission lines and equipment. Recognizing where a signal falls in the spectrum guides the selection of cable suited to its propagation and impedance needs, supporting reliable performance across the system.
Because propagation in this band changes with the time of day, systems working at medium frequency are engineered with those conditions in mind, and the supporting transmission lines are chosen to suit both the frequency and the power the equipment handles across that range.
At Windy City Wire, the focus on coaxial and signal cable for commercial communication spans the full range of frequencies a facility may encounter. Understanding band designations like medium frequency supports the selection of cable matched to the requirements of each communication application.
MF (Medium Frequency)
ITU (International Telecommunication Union), which defines radio frequency band designations