| 摘要 |
1. Apparatus for control of the operating frequency (F), associated with an operating magnetic field (H), of a gyromagnetic resonance filter (Y1 , Y2 , Y3 ), as a function of a reference frequency (FO) to which corresponds, theoretically at least, a reference magnetic field (HO), characterised in that it includes a frequency discriminator (Y4 , Y5 , DELTA T1, A1) physically integrated with the filter and subject to the conditions prevailing in the latter, the discriminator having first and second gyromagnetic resonators (Y4 , Y5 ) subject not only to the operating magnetic field of the filter, but also to supplementary first and second local magnetic fields (DELTA H + DELTA h, DELTA H - DELTA h) forming respectively, with the operating magnetic field of the filter (H), first and second resultant magnetic fields, the intensities of which are respectively greater and less than that of the reference magnetic field, and in that the resonators are both excited by an electromagnetic signal (DELTA L) at the reference frequency (FO) so as to provide, at respective outputs, output signals respectively dependent each on the amplitude and/or sign of the imbalance between the resultant magnetic field to which the resonator concerned is subject, and the reference magnetic field corresponding to the reference frequency signal that said resonator receives, the apparatus including control elements (DELTA T1, DELTA T2, A1, A2, CTC) receiving the two output signals and acting on the intensity of the operating magnetic field (H) of the filter in a sense so as to reduce the amplitude and/or change the direction of the imbalance affecting the resonator having the greater imbalance. |
