Abstract: A lightweight, transistorized, inverter circuit is particularly adapted for starting and operating a screw-in compact fluorescent lamp intended for incandescent lamp replacement. Household-type AC is converted to DC with one terminal connected to the center tap of a transformer primary through a choke which constitutes a high impedance at the operating frequency. A tuned circuit capacitor is connected across the transformer primary and a current-limiting capacitor and the lamp to be operated are connected in series across the transformer primary. A pair of transistors are connected in push-pull arrangement between the end portions of the transformer primary and the other terminal of the DC source, with the base electrodes of the transistors connected to the transformer secondary winding so that the push-pull connected transistors oscillate at the tuned circuit resonant frequency which is determined by the inductance of the transformer primary winding and the total capacitance of the connected capacitor means.

Abstract: The work is scanned by acoustic energy from a focused-arc transducer and from an acoustic-lens transducer. An echo-ranging subassembly energizes the focused-arc transducer and processes the echo trains relfected from the lines or pencils in the work along which the acoustic energy is focused. A holographic echo-processing subassembly is connected to energize the acoustic-lens transducer and to process the echoes reflected from the work where the energy from the acoustic lens impinges. The echo-ranging subassembly and the holographic echo-processing subassembly are enabled alternately and the acoustic energy from the focused-arc transducer and from the acoustic-lens transducer impinge on, and is reflected by, each of a succession of elemental areas of the work. The outputs of the echo-ranging subassembly and of the holographic echo-processing subassembly are supplied to an elastic store which may include one or more shift registers.

Abstract: High frequency electrodeless (HFE) lamp has high-permeability core such as ferrite positioned in energy transferring relationship with respect to the phosphor-coated lamp envelope. The core forms a part of a tuned circuit output for a radio-frequency energizing source and during lamp operation, the resulting electromagnetic fields generated within the lamp envelope create a discharge which in turn generates radiations to excite the phosphor to produce visible light. The core is specially designed to include narrow gap means of low-permeability substance and this gap improves lamp performance by providing the dual function of stabilizing the output frequency of the tuned circuit to compensate for variations in permeability of the core and, in addition, the resulting increased Q of the tuned circuit substantially suppresses harmonics of the resonant frequency which are undesirable in such a lamp.

Abstract: High-frequency electrodeless discharge device is operated by radio-frequency energy generated by an oscillator operating in Class E mode. By proper selection of the oscillator circuit components, a load-network capacitor can be eliminated along with an inductor which is normally required to pass direct current to the transistor switch portion of the oscillator. The elimination of these elements permits the oscillator to be packaged in compact fashion. The discharge device incorporates a looped core of high permeability material which forms a part of the tuned circuit output portion of the oscillator and the radio frequency energy electromagnetic fields passed through and about the core and within the envelope of the device excite a discharge-sustaining medium to generate plasma which is converted to visible radiations.

Abstract: A method and apparatus for lowering the contrast range between a welding arc and its surroundings for remote viewing of an arc welding process. A monochromatic light source (10) is used to illuminate the area surrounding the welding arc (18) and a narrow band interference filter (22) tuned to the wavelength of the monochromatic light (10), is placed in front of a viewing camera (24). The monochromatic light enhances the arc background while the filter (22) attenuates the arc illumination that reaches the camera for a more desirable contrast ratio so that the arc, weld puddle and surrounding area can be visible with a high degree of definition on the monitor.

Abstract: In an educational television system, a constructed answer system is based on the use of code pulses that are repeated cyclically during their concealed transmission within a television video waveform. Indicia, e.g., letters of a word or formula, are preloaded into a store in the form of binary code as an output from a punched tape reader or an encoder for a keyboard. The encoder is reset following each transfer of encoded indicia to the store which is indexed by a shift register to render responsive successive columns of flip-flops in a matrixed arrangement. The store includes a column of AND gates to store a permanent "recycle code". The reading of the store is clocked by modified sync pulses applied by a shift register to a matrix arrangement of interconnected AND gates that are also connected to the output of the flip-flops. The readout of the store is repeated cyclically by a logic register that compares the number of encoded indicia in the store with the number of encoded indicia read from the store.

Abstract: Apparatus for transmitting and receiving a plurality of separate pictures or scenes on a single television carrier signal such that a different picture appears in each quadrant of a television receiving tube, and including means for blanking out all but one quadrant and for centering and expanding that quadrant to fill the entire screen of the receiving tube. This is accomplished by separating the sync signals from the video, followed by delaying the sync signals and recombining them with the video such that the video portion, representing one quadrant, is essentially centered between horizontal and vertical sync pulses. Expansion of the single quadrant after it is centered on the tube is achieved by increasing the amplitude of the vertical and horizontal sweep waveforms.