Abstract: A ladder filter wherein an inside of a case is partitioned by a vertical partition wall into four containing portions. Each containing portion contains at least one piezoresonator, and an input terminal, an output terminal and junction terminals are portioned out into the containing portions. A grounding terminal is contained at a bottom of the case.

Abstract: An amalgam system for optimizing the mercury vapor pressure of an electrodeless discharge fluorescent lamp is disclosed. A coil network induces an electric discharge in a gas mixture contained in a sealed lamp vessel. An amalgam is supported in the discharge and thermally isolated from the lamp vessel by a thin glass strand. The discharge transfers power directly to the amalgam, thus quickly heating the amalgam. Rapid heating of the amalgam provides a rapid increase in mercury vapor pressure in the lamp so that the light output rises quickly when the lamp is energized. An impedance matching and filter network is constructed such that, in combination with the coil/plasma load, it provides a desired steady-state impedance and a desired start-up impedance.

Abstract: A piezoelectric device which has a piezoelectric substrate and a plurality of piezoelectric resonators provided on the substrate. The piezoelectric resonators are an energy-confining type, and when a voltage is impressed on the piezoelectric resonators, each of the piezoelectric resonators generates a primary vibration in a direction of the thickness of the substrate and a secondary vibration in a direction on the surface of the substrate. The secondary vibration, in the form of an oscillatory wave, is propagated on the surface of the substrate and is attenuated gradually. At least two of the piezoelectric resonators have propagation paths of secondary vibrations which are substantially parallel to each other so as not to intersect within the substrate.

Abstract: A transmission line resonator is disclosed which has a resonance frequency that is electrically controllable by control voltage. A reactive circuit is coupled in parallel between two coupling points on the transmission line resonator. The reactive value of the reactive circuit is changed by the control voltage. The reactive circuit can be inductive or capacitive. The control voltage can switch the reactive circuit in parallel with a part of the transmission line resonator between the coupling points, or can control the capacitance value of a capacitance diode disposed in parallel with a part of the transmission line resonator between the coupling points.

Abstract: The invention relates to an intelligent lamp or an intelligent contact terminal for a lamp, which can be used in a lighting system comprising a plurality of individually controlled lamps linked in a common power-supply circuit and an operation control device for transmitting a desired operation control signal to electronic control elements, associated with the lamp or the contact terminal and reacting or failing to react selectively to various control signals. Together with the lamp or its contact terminal, said electronic control elements provide a single replaceable component which, on the basis of a message included in the operation control signal, identifies itself to serve as an appropriate lamp. In addition, the electronic control elements monitor the condition of itself and that of the lamp and, if necessary, produce a fault indication.

Abstract: A discharging lamp lighting apparatus is provided to perform lighting control of high voltage discharging lamps such as high pressure sodium lamp or metal halide lamp. In the discharging lamp lighting apparatus, a control section determines a power control pattern balancing with stored discharging lamp stable voltage so as to perform power control of the discharging lamp according to the pattern. If no voltage is stored, the control section performs the power control according to a power control pattern balancing with the minimum rated voltage of the discharging lamp. Then, it is possible to store the voltage when the discharging lamp is stabilized. If the discharging lamp is exchanged, the control section erases contents in stable voltage storing means so as to perform the lighting control of the discharging lamp from an initial state.

Abstract: A three-terminal resonator device (200) resonant at a resonant frequency has a first terminal (201), a second terminal (202), and a common terminal (203). The resonator includes a surface acoustic wave transducer (290) disposed on a piezoelectric substrate (201). The SAW transducer (290) is comprised of a first sub-transducer (210) and a second sub-transducer (220) which respectively include a first set of electrodes (211,213) and a second set of electrodes (221,223). One of the electrodes of each of the first set and the second set of electrodes respectively provide the first terminal (201) and the second terminal (203). The other terminals of the first and second set of electrodes are connected at the common terminal (203) to provide a serial connection between the first sub-transducer (210), and the second sub-transducer (220).

Abstract: The present invention relates to a radio frequency filter the resonators (6,7) of which are made up of a wire wound into a cylindrical coil comprising a number of turns and of a surrounding casing (41). Finger-like projections (3) of an insulating plate (1) support the conical coils from the inside, and the coupling to the resonator is from a microstrip line (8), at a tap point (21), on the insulating plate. Each cylindrical coil has, adjoining the first turn, a straight portion (2) which is parallel to the axis of the cylindrical coil and extends towards the bottom plate (44) of the filter. On the inside surface of the bottom plate (44) there is a lead (51) one end (E) of which is short-circuited and the other end open, and the tip (12) of the straight portion (2) adjoining the cylindrical coil (6) is in contact with this lead (51).

Abstract: To control preheating current flow through a fluorescent lamp supplied from high-frequency inverter (T1, T2, A) and a series resonance circuit, an electronic switching control circuit (SC) is connected to the preheating circuit of at least one electrode filament (E1, E2, E10, E20, E11, E21, E12, E22) of one or more of the fluorescent lamps. The switching control circuit senses the voltage across the pair of terminals (T1, T1', T2, T2') of the electrode filaments, or across all the electrode filaments. Since fluorescent lamp filaments have a positive temperature coefficient of resistance, the voltage across the filaments will rise as the filament or filaments of the lamp reach electron emission temperature. This rise in voltage is sensed, for example, by a threshold circuit which may include a Zener diode, and is used to break the preheating circuit.

Abstract: A piezoelectric resonator (10) with an attenuated spurious response. The resonator (10) includes a piezoelectric crystal plate (12) having opposite surfaces (14, 16), electrodes (18, 24) positioned in overlying relationship on each of the opposite surfaces (14, 16), the electrodes (18, 24) being substantially coextensive and opposite, and providing a primary frequency mode of operation and spurious modes upon suitable energization, and one of the electrodes (18, 24) having a curved extension (23) for reducing spurious modes.

Abstract: A transmission line filter having an improved attenuation characteristic is disclosed. The transmission line filter includes at least input-side and output-side resonators disposed in a dielectric layer which are inductively coupled with each other. Additionally, intermediate resonators may be disposed between the input-side and output-side resonators. Further, input and output electrodes are provided in another dielectric layer, at least one of which is in an opposed facing relationship to a portion of the input-side resonator and a portion of the output-side resonator, so as to overlap only those portions of the input-side and output-side resonators.

Abstract: A ladder type piezoelectric filter of the present invention is made usable in high frequency ranges by employing a piezoelectric resonator having the second harmonic wave mode SM. A series resonator and a parallel resonator of the ladder type piezoelectric filter of the present invention are so arranged that center electrode regions and outer electrode regions are mutually polarized along opposite directions, and the center electrode regions are connected to the outer electrode regions, respectively.

Abstract: There is provided a ladder type electric filter having a pair of vertically arranged parallel resonators and a pair of series resonators arranged side by side above the parallel resonators and, at the same time, held free from degradation in the performance of the filter, wherein the abutting surfaces of the raised connecting sections of a connecting terminal member that are held in close contact with the respective lower surface-electrodes of the series resonators partly overlap with the abutting surface of the raised connecting section of an output terminal member that is held in close contact with the upper surface-electrode of the upper parallel resonator if viewed from above.

Abstract: In the mechanical supporting of the resonator coil it is known to use around the resonator coil an injection moulded plastic U-shaped binder ring, with the loops of the coil running through the arms in the binder ring. The resonator wire can also be wound around a plastic body. The methods of the prior art considerably weaken the Q value of the resonator. According to the invention it is possible to achieve good supporting, without a weakening of the Q value, in such a way that the resonator coil (1) is supported from at least one point by a supporting leg (6) of metal, which one end is fastened to the wire of the resonator coil (1) and the other end is fastened to an insulation piece (8) having low losses, which in turn is fastened to the installation plate.

Abstract: A method of adjusting a frequency response in a ladder-type electric filter having a pair of parallel resonators and a pair of strip-shaped series resonators arranged in a predetermined manner to form a fundamental filter circuit in which at least one of corner portions of each of the strip-shaped series resonators is beveled without changing its length L to regulate its resonance frequency so that the device can be stored within a case without displacing it from its proper position and held in contact with a contact at its node of vibration.

Abstract: An improved fluorescent light ballast circuit extends the on/off life of a florescent lamp within a lighting circuit having a pair of series connected fluorescent lamps. The ballast circuit includes a DC pulse generation circuit, filtering and voltage regulation circuitry, a step-up voltage transformer, and a current altering circuit which alters the current within selected filaments within the lamps. The current altering circuit includes a diode and a coil winding which connect across a filament within one of the fluorescent lamps. The net effect of the current altering circuit is to increase the voltage supplied across the lamp connected to the current altering circuit so that the voltage levels across both lamps are balanced.

Abstract: The present invention discloses a frequency tunable filter which includes an electromagnetic (E-M) wave propagation line which includes a microstrip and a ground plane in the substrate for transmitting a sequence of E-M signals via the propagation line. The E-M wave propagation line includes a frequency tuning mechanism, i.e., the magnetic layer, which is capable of utilizing a ferromagnetic anti-resonance frequency response to the E-M signals transmitted via the propagation line for controlling and frequency tuning the E-M signal transmission. In one of the preferred embodiments, the E-M wave propagation line includes a microstrip forming on the top surface of a dielectric or semiconductor substrate for receiving and transmitting the E-M signals and a ground plane forming on the bottom surface of the semiconductor substrate. And, the frequency tuning mechanism includes a ferromagnetic layer formed in the substrate between the microstrip and the ground plane.

Abstract: The present invention is concerned with a power supply circuit for discharge lamps, especially those intended for vehicle headlamps. It also relates to a headlamp having a power supply circuit. The latter has a half wave bridge structure, the discharge lamp being connected to the midpoint of the bridge. A primary of a transformer works as a quasi-resonant wave generator under the switching effect of a quasi-resonant interrupter, which is controlled by a control circuit for controlling the electrical state of the discharge lamp. In addition, starting of the lamp is effected by a second transformer, the primary of which is connected to a spark gap having a suitably chosen triggering voltage.

Abstract: An method of operating a neon stop lamp for a vehicle is described. By adjusting the lamp pressure, the then controlling the frequency and pulse width of the power, the lamp efficiency can be increased, while also shifting the chromaticity for the lamp to comply with automotive standards. The result is a small, efficient light source whose light may be reflected and focused, and whose color is correct for vehicle warning lights.

Abstract: A surface acoustic wave device for propagating a surface acoustic wave having input and output transducers and a multistrip coupler formed on the surface of a substrate. The input and output transducers each have two opposite electrodes having a plurality of electrode fingers extending toward their opposites and meshing with the electrode fingers of their opposites. The multistrip coupler has strip lines of a configuration wherein portions of at least some of the coupler strip lines are more widely spaced from adjacent patterns than other portions of the coupler strip lines. The width of these more widely spaced portions of at least one of the coupler strip lines which are more widely spaced from adjacent patterns is made larger than the width of the other portions of the at least one coupler strip line to compensate for the thinning effect of the lithography process.