Single and multiple ferrite crystal resonator, oscillator, and filter
coupling structures are disclosed. In one embodiment, a single ferrite
crystal resonator coupling structure is configured as a single pole
YIG-tuned-oscillator (YTO) coupling structure. The YTO coupling structure
includes a circuit substrate having an upper and a lower side. The circuit
substrate includes an aperture extending through the circuit substrate
between first and second openings on the upper and lower sides,
respectively. The aperture is configured to permit rotation of a ferrite
crystal disposable at least partially therein about a plurality of axes
whereby a desirable axis of the ferrite crystal is alignable with a
magnetic field within the aperture. At least one coupling line through
which an electric current can be directed, which extends between a first
end and a second end of the first opening of the aperture across at least
a portion of the first opening of the aperture. The coupling line or lines
may be etched on the lower surface of a coupling substrate positioned over
the aperture. A bipolar transistor is mounted on the circuit substrate
with an emitter terminal thereof electrically connected to the first end
of the coupling line or lines.
