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This paper presents a novel hybrid bias concept for liquid crystal (LC) filter by using simultaneously electric and magnetic bias fields. It enables continuous tuning with a simplified electrode design, decreased number of electrodes and reduced bias voltage. Furthermore, the tuning efficiency is increased, since the homogeneous bias fields enable a full exploitation of the LC&#x0027;s anisotropy. To demonstrate this concept, a novel reconfigurable gap waveguide two-pole bandpass filter with tunable center frequency and coupling elements is designed at <inline-formula><tex-math notation="LaTeX">$30 \,\mathrm{GHz}$</tex-math></inline-formula>. Liquid crystal technology is applied as tunable material, whereby tunability of the center frequency and coupling elements is obtained by controlling the LC&#x0027;s effective permittivity. The presented filter&#x0027;s center frequency can be tuned from <inline-formula><tex-math notation="LaTeX">$28.88 \,\mathrm{GHz}\,\mathrm{to}\, 29.88 \,\mathrm{GHz}$</tex-math></inline-formula> with a maximum bias voltage of 100 V, with a return loss of 20 dB and low insertion loss of only 1.65 to 1.95 dB.