A continuous range or spectrum of frequencies that extends from one limiting frequency to another. Note 1: The frequency range for given equipment specifies the frequencies at which the equipment is operable. For example, filters pass or stop certain bands of frequencies. The frequency range for propagation indicates the frequencies at which electromagnetic wave propagation in certain modes or paths is possible over given distances. Frequency allocation, however, is made in terms of bands of frequencies. There is little, if any, conceptual difference between a range of frequencies and a band of frequencies. Note 2: "Frequency band" usually identifies a specific band of frequencies in the Tables of Frequency Allocations.