Magnetically tunable composite ferrite-dielectric microwave elements

•Magnetically tuned composite resonators were manufactured and investigated.•Nature Q-factor rising and thermal stability for BaTi4O9 system was investigated.•Composite resonators change their resonance frequency due influence magnetic field.•There is a need of the work on the decrease of “reverse” energy losses.•It was shown theoretical possibility to reach high non-reciprocity of resonators.