Abstract: Radioactive materials are used to assist in starting a discharge in an electrodeless light source. The radioactive emissions predispose on the inner surface of the lamp envelope loosely bound charges which thereafter assist in initiating discharge. The radioactive material can be enclosed within the lamp envelope in gaseous or non-gaseous form. Preferred materials are krypton 85 and americium 241. In addition, the radioactive material can be dispersed in the lamp envelope material or can be a pellet imbedded in the envelope material. Finally, the radioactive material can be located in the termination fixture. Sources of alpha particles, beta particles, or gamma rays are suitable. Because charges accumulate with time on the inner surface of the lamp envelope, activity levels as low as 10.sup.-8 curie are effective as starting aids.

Abstract: Electrical power is converted into rectangular waves, which are loosely coupled to a fluorescent lamp. A parallel tank circuit resonant near the fundamental or a harmonic of the square wave frequency is connected between the electrodes of the lamp. The electrodes of the lamp each have a pair of terminals across which an electrical potential is applied to heat the electrodes while starting the lamp. Power is applied across the first and second electrodes while starting the lamp and after starting the lamp. Power is also applied and/or the pair of terminals of the second electrode while starting the lamp and after starting the lamp. The ratio of voltage across the first and second electrodes to the voltage across the pair of terminals is such as to properly preheat the electrodes and prevent arcing between each pair of terminals, and arcing between the first and second electrodes while starting.

Abstract: There is disclosed an automatic light system for a moving vehicle wherein there is provided an on/off control feature responsive to ambient light conditions and responsive to the activation of windshield wipers. Included in the on/off control feature is electronics for a built in delay to delay changes in the on/off condition of the headlights caused by sudden or gradual darkness, sudden or gradual light, and the starting of the vehicle. The automatic light system includes a high/low beam control feature which is responsive to oncoming or passing cars.

Abstract: Mixed light lamps require a complicated construction so as to be able to suspend the filament and the discharge lamp. In a mixed light lamp according to the invention a bipartite filament of coiled-coil wire is used, the parts of which are each stretched between one pole wire and a current supply conductor of the discharge lamp.

Abstract: Efficient starting of solenoidal electric field discharge lamps is effected with a start winding disposed on the same core with the ballast reactance. This placement of the start winding possesses certain advantages over other methods of lamp starting, and in particular it facilitates hot restart of the lamp.

Abstract: A voltage source adapted to excite a gas-ionization electrode so as to generate copious amounts of ionized gas without, however, producing measurable amounts of undesirable reactive or toxic chemical by-products. Yielded by the source is a unipolar voltage wave having a steady state DC component which, though below the ionization potential, serves to condition the gas to promote ionization. Imposed on the steady-state component is a gas-ionization component in the form of low-frequency surges, each composed of a short series of high-frequency pulses having a brief duration and an extremely high peak amplitude. The duration of the surge pulses is insufficient to break down the gas chemically, but the amplitude thereof is such as to effect intense gas ionization. The steady-state component prevents the electric field from collapsing completely in the intervals between pulses, thereby keeping the gas at a level approaching its ionization potential.

Abstract: A thin disc-like device for attachment to the base end of an incandescent light bulb to provide an auxiliary voltage reducing circuit interfaced between the central base contacts of the light bulb and its cooperating lampholder for purposes of extending the rated life of the light bulb. The device is made up of a generally annular insulator base, which protectively houses, locates and mounts a laminated contact assembly made up of a pair of registeringly disposed brass or copper foil electrical conductor contact plates separated by an intervening sheet insulator; the conductor plates having interfacial soldered connections with an interposed flat leaderless silicon rectifier chip. A compressible annular mounting gasket is adhesively secured to the upper side of the contact assembly, its base housing and the base of the light bulb.

Abstract: A thin-walled grid of pyrolytic graphite for a high-power electron tube such as a triode or tetrode has a lower end in the form of a bell-shaped sleeve provided with uniformly spaced longitudinal slots which stop short of the edge of the sleeve. The solid edge portion thus formed beneath each slot serves to fit the sleeve over a metal ring of the electron tube base. The grid sleeve is clamped against the metal ring by means of screws engaged in internally-threaded bores of the ring. The edge portions of the graphite sleeve are thus fractured so as to form longitudinal strips which compensate for differences in expansion between the graphite and the metal while ensuring good electrical contact.

Abstract: A means for regulating the power of a fluorescent tube in a vehicle supplied by a DC source by providing the control circuit of an oscillator transistor of an inverter with an adjustable RC circuit. Even very much dimmed tubes can be lighted with the use of a switch by-passing the RC circuit.

Abstract: An X-ray tube including a tubular envelope having therein an X-ray target comprised of a support body made of a first material and provided with a composite surface layer comprising a controlled gradient of a second material disposed in the first material, one of the materials being an X-ray emissive material and the other of the materials being a heat absorbent material, and an electron emitting cathode disposed to beam electrons onto a focal spot area of the composite surface layer.

Abstract: A gun for a linear-beam electron tube has a control grid for modulating the beam current which consists of an array of conductive web elements whose spacing from each other is much larger than their spacing from the concave emissive surface of the cathode. It was found that when this condition is met the grid can be operated at cathode potential while beam current is being drawn without distorting the electric accelerating field enough to ruin the focusing of the beam. Thus, when the grid is used to pulse the beam current on and off, it can have zero bias in the "on" condition, whereby the pulse modulator can be greatly simplified.

Abstract: There is disclosed an apparatus for diagnosing milk secretion disorders in animals such as cows. The apparatus is based upon an electric detection of deviations from the properties of a standard milk secretion, and comprises a holder carrying a diagnostic dish divided by partition walls into a number of diagnostic units corresponding to the number of teats of the animal. The diagnostic units are each provided with a measuring probe exposed to the mouths of scavenging nozzles and with a circuit for evaluating the milk quality as by its electrical conductivity. The outlet of said circuit is connected to the inlet of a display indicating, for example, when the quality of the milk in each diagnostic unit exceeds a predetermined value.

Abstract: A spark plug incorporating a winding type inductor has a low noise level from a low frequency range to a high frequency range. The spark plug comprises a ceramic insulator having a bore, a metal fitting surrounding the insulator, a center electrode, a terminal electrode and a noise-attenuation element arranged in the bore of the ceramic insulator and sealed to the center and terminal electrodes through glass, said noise-attenuation element consisting of an inductance component alone or a combination of an inductance component and a resistance component, and said inductance component being arranged extending to both sides of a sealed level for the noise-attenuation element formed by an end of the metal fitting which is connected to the insulator.

Abstract: A vehicle headlight is disclosed comprising a dirt sensor for sensing dirt on a diffuser disk of the headlight. The dirt sensor receives the light of a lamp of the headlight scattered back due to dirt on the diffuser disk and is shielded against the light emanating directly from the lamp and emanating indirectly via a reflector. The dirt sensor of the headlight is arranged at a point outside of the reflector to which the scattered-back light passes via reflection on the reflector whereby changes to the reflector for accommodating the dirt sensor and the concomitant reduction of the effective surface area of the reflector are avoided.

Abstract: In electric lamps according to the invention the alkali-alumino-borosilicate glass of the pinch seal of the lamp envelope is directly fused to the molybdenum current supply wire of diameter D. A vacuum-tight seal is obtained in that the glass inside the lamp envelope extends over the current supply wire in a layer which is thinner than D/2 at least over a length of D/2. For use in both incandescent and discharge lamps.

Abstract: A directly heated cathode for electron tube having a stable electron emission characteristic and a low cut-off voltage is provided. The cathode comprises a base metal of an alloy consisting essentially of 20-30% by weight of tungsten and a trace amount to 0.25% by weight of zirconium, the balance being nickel, binder dots of metallic nickel powders distributed on a flat part at the front side of the base metal, and a layer of thermoelectron emission oxides laid on the flat part at the front side of the base metal. The layer of thermoelectron emission oxides is in direct contact with the flat part through clearances among the binder dots of the metallic nickel powders.

Abstract: A lighting inverter for operating an electrical discharge lamp from a direct current power source. The inverter includes a resonant feedback inverter which converts the output of the d.c. power source to an alternating current output and regulates the a.c. inverter output voltage level by varying the frequency thereof. A ballast filter is coupled to the regulated output of the resonant feedback inverter and is formed by a series circuit of a ballast inductor and a ballast capacitor. Connected across the capacitor is the discharge lamp. Appropriate circuit parameters such as ballast inductance, ballast capacitance, inverter operating frequency, and the inverter resonant frequency are selected to maintain almost unity power factor at the input to the ballast filter.

Abstract: A conductivity probe having a cylindrical body with an annular open-sided groove in which the electrodes are disposed, and a sliding cover wall for the groove biased to a position covering the groove but easily operable with one hand to slide the cover so as to open the groove. Viscous or slurried material can easily enter the groove, be trapped and confined for the conductivity measurement and then readily washed from the groove and surrounding parts for the next operation.

Abstract: A method of and an apparatus for determining the dielectric breakdown chateristics and size of membrane-sheathed particles such as living-organism cells and the apparent size of such particles after breakdown of the membrane, makes use of two measuring orifices traversed by an electrolyte across which an increasing electric field is applied during the measuring process in which the particles successively traverse one of the orifices. The current through the measuring orifice deviates from the linear with increasing field generated preferably by a sawtooth voltage, the current change being used to measure the particle variables stated.

Abstract: A cathode for an electron gun in which a lanthanum hexaboride cap has an internal recess which accommodates a pyrolytic graphite heater element. The cap is cup-shaped, while the heater element is in the form of a frustum of a cone and is resiliently maintained in abutting relationship with the cap by a corrugated tubular member and an assembly of rigid tubes. A cylindrical shell surrounds the periphery of the cap, and a pair of generally conical shielding elements are located in position to intercept stray thermal radiation from the heater element. All of these cathode components are supported in coaxial relationship with each other within the electron gun.