Abstract: A voltage controlled oscillator having a resonator wherein a substrate is made up of a plurality of dielectric layers; an inductor functioning conductive film and grounding electrode films are each formed at a boundary surface of one of the dielectric layers; the earth electrode films are arranged, in the direction in which the dielectric layers are laminated, at both sides of the conductor functioning conductive film; the inductor functioning conductive film and the grounding electrode films constitute the resonator; and electric lands are formed on the surface of the substrate so that other components of the oscillator are mounted on the surface of the substrate.

Abstract: In an oscillator employing a triplate type stripline, earth (ground) electrodes are formed only on an opposite pair of side surfaces of a substrate in which the stripline is embedded. An oscillation circuit mounted on the substrate is covered with a shielding case and the remaining side surfaces of the substrate, which are provided with no earth electrodes, are covered with shielding plates which are provided on the shielding case. Connecting portions of the shielding case are electrically connected with the earth electrodes by soldering. Thus, the stripline is electromagnetically shielded in a simple manner so that it is possible to easily manufacture an oscillator employing a stripline at a low cost.

Abstract: An oscillator employing a strip line of tri-plate structure as a resonant element comprising a substrate having a strip line electrode embedded therein and a pair of grounding electrodes opposed to each other with the strip line electrode therebetween, neither of the pair of grounding electrodes being exposed on an upper main surface of the substrate, an oscillation circuit portion provided on the upper main surface of the substrate, a capacitor electrode provided on the upper main surface of the substrate, the capacitor electrode being opposed to the embedded grounding electrode, wherein one end of the strip line electrode is connected to the capacitor electrode and the oscillation circuit portion through a first connecting electrode extending from the above one end of the strip line electrode to the upper main surface of the substrate and wherein the other end of the strip line electrode is connected to at least one of the pair of grounding electrodes through a second connecting electrode.