using a harmonic phase-locked loop, i.e. a loop which can be locked to one of a number of harmonically related frequencies applied to it (H03L7/22 takes precedence)

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Automatic control of frequency or phase; Synchronisation > using a reference signal applied to a frequency- or phase-locked loop > Indirect frequency synthesis, i.e. generating a desired one of a number of predetermined frequencies using a frequency- or phase-locked loop > using a harmonic phase-locked loop, i.e. a loop which can be locked to one of a number of harmonically related frequencies applied to it (H03L7/22 takes precedence)