Generations of Oscillations with Equally Spaced Frequencies in a Given Band

One or two crystal oscillators determine the lowest and the highest frequency of the band, faand fb, respectively. A self-excited oscillator is stabilized to the mean frequency, f1, of the band by comparison of the difference frequenciesf_{1}-f_{a}andf_{b}-f_{1}- A second oscillator stage can then be stabilized similarly, either to the midfrequency between f1and faor between fland fb. In each further stage the number of frequencies to which the corresponding oscillators can be stabilized is doubled. Thus, for example, ten stages make any of 1,047 frequencies available. Further methods are described where each stage triples or quadruples the capacity of the system.