Abstract: A conductive adhesive for use in membrane switch and printed circuit technologies consists essentially of a resin modified copolymer of butadiene and styrene and a conductive element. The conductive element is preferably a material such as acetylene black and is more than two percent and less than 40 percent by weight of the adhesive. The conductive adhesive may be used to secure the membrane and substrate of a membrane-type switch thereby providing a conductive path between the membrane and substrate. The adhesive may also be used to attach a membrane switch tail to an associated printed circuit board or the like, again with the conductive properties of the adhesive providing a current path as well as the conventional adhesion between the two parts.

Abstract: A cable television converter includes an oscillator and mixer for conversion of a selected input television channel to the specific output frequency of the converter. There is a program selection device, and a memory responsive thereto whereby a subscriber may designate certain channels for conversion to the output frequency. The program selection device provides for restricting access to only those designated channels in the memory whereby a subscriber may control access of members of the household to only certain permitted channels.

Abstract: A coding and decoding system for video and audio signals includes means at the transmitter for deriving clock and internal timing signals from the video signal. The internal timing signals are utilized at the transmitter to provide digital audio data representative of the program audio signal. The digital audio data is derived by sampling the program audio signal during horizontal lines of the video signal. The synchronizing information in the horizontal and vertical blanking intervals of the video signal is suppressed and the digital audio data and data representative of a decoder clock signal are inserted in the horizontal blanking intervals. Vertical reference signal data is inserted into the vertical blanking intervals of the video signal as it is transmitted. At the decoder there are means for reconstituting the audio signal from the digital audio data.

Abstract: This invention relates to flexible materials for use in electrical devices, such as membrane switches. The flexible component of the device is formed of paper.

Abstract: A keyboard crosspoint encoder and a method of operating it which provide N-key rollover. The encoder has an information storage device. The matrix of crosspoint switches is scanned to determine the status of each switch and this information is stored in an array in the storage device. This array is checked to determine if a phantom switch condition exists. The encoder then provides an output of all newly-closed switches which are not involved in a phantom switch condition.

Abstract: A flexible connector includes a flat thin insulating base and a plurality of spaced conductive paths formed thereon. There are means for providing selective interconnection between certain conductive paths on the base, which means includes a thin defined insulating patch positioned upon a selective area of the base and conductive paths. A connecting conductive path is formed on the insulating patch and extends therethrough into electrical contact with said certain conductive paths.

Abstract: This invention relates to an arrangement for attaching discrete electrical components to a generally flat layer of sheet material. Both mechanical and electrical connections are provided by the attachment elements of the present invention. One form of the invention is directed to a membrane switch keyboard wherein one of the layers of the membrane switch has a tail extending therefrom. The tail has a free end which is adhesively secured to some portion of the keyboard. Conductive traces are formed on the tail and extend to the free end where they contact the leads of an electrical component. The component is held between the tail and the keyboard. In another aspect, which may be applied to the membrane switch keyboard just described, the invention includes a sheet material having two or more slits cut therein for each of the component's leads. The slits are cut in a portion of the sheet having conductive traces formed thereon.

Abstract: A membrane switch has a substrate, a flexible membrane and an intervening spacer. Switch contacts are formed on the top surface of the substrate and the underside of the membrane in spaced, facing relation. A hole in the spacer in register with the switch contacts allows the contacts to move together in response to pressure exerted on the membrane. An auxiliary electrical device can be incorporated into the membrane switch through an opening in the membrane which provides access to a current supply circuit which is formed on the top surface of the spacer. The auxiliary device is held in place in electrical contact with the current supply circuit on the spacer. A pair of current supply leads provide electrical power to the current supply circuit. In a preferred embodiment at least one of the current supply leads is formed on the underside of the membrane, in contact with the current supply circuit and also connected to the switch contact on the membrane.

Abstract: Membrane switch technology is applied to the more conventional switch construction found in a rotary switch. Specifically, there may be a membrane and a substrate, each having electrical contacts or contact means formed thereon. A spacer having openings or opening means is positioned between the membrane and the substrate. The spacer is rotated between the membrane and substrate to vary the position of the opening which permits membrane contacts to be moved through the opening to form a switch closure.

Abstract: A switching device, for example a membrane switch, having an interconnect tail for electrically connecting the switching device to a circuit board. The tail has conductive traces formed thereon, which are in circuit with the conductive elements of the switching device. The conductive traces on the tail are raised from the plane of the tail thus making the traces the most prominent part of the tail. This structure assures electrical contact with the circuit board.

Abstract: A low profile switch has a base with a contact pin extending through the base. The pin is press fit into a hole in the base such that the pin itself seals that hole. A movable contact including a central dome portion overlies the contact pin. The dome portion is movable into and out of contact with the pin. A gasket is disposed between the periphery of the movable contact and the base. A retainer clamps the movable contact against the gasket and urges the gasket into sealing engagement with the base to provide a sealed interior for the switch. The retainer has legs which are clinched on the under side of the base. A slidable button provides an actuating member.

Abstract: A product useful in the manufacture of printed circuits includes a carrier layer of copper having a thickness on the order of about 10-15 microns. A thin layer of copper having a thickness in the range of 1-12 microns, and which will provide the conductive path for the printed circuit, is secured to the copper carrier by an intermediate metallic layer positioned therebetween and secured to both layers of copper. The intermediate layer has a thickness in the range of 0.1-2.0 microns and is selected from the group consisting of nickel, a nickel-tin alloy, a nickel-iron alloy, lead and a tin-lead alloy. The intermediate layer adheres sufficiently to the thin layer of copper to prevent removal thereof during the etching process which removes the carrier layer of copper. The described thin metallic foil is bonded upon opposite sides of a suitable dielectric which may be a reinforced or non-reinforced epoxy or any one of a number of other suitable materials for forming the core of a printed circuit board.

Abstract: An assembly for manufacture of a membrane switch includes a composite formed of first and second layers, one substantially thicker than the other, with the composite having a size and shape to form both outer members of a membrane switch when folded back upon itself. Metallic conductors, preferably silver, are formed on the composite prior to folding. A spacer member having spaced openings therein and extending over approximately half of the area of the composite is positioned thereupon. After the composite is folded over the spacer member, laminating heat and pressure are applied to the assembly with the result that a bond is formed between the spacer member and composite and between the layers of the composite.

Abstract: This invention relates to a method of fabricating a membrane switch of the type having a substrate, a flexible membrane, electrical conductors formed on the membrane and substrate, and an intervening spacer between the sets of conductors. The conductors include a plurality of switch sites which are in facing relation to define a specific switch. The spacer means comprises a plurality of individual spacer areas which are located remote from the switch sites. The manufacturing method uses a multiple pass screen printing operation. During the first pass a set of conductors is formed from conductive ink on either the membrane or substrate. Also, during the first screening pass a first layer of the spacer areas is formed from the same conductive material as the set of conductors. On subsequent screening passes additional layers are deposited on the spacer areas to build up the thickness of the areas so that the spacer thickness is greater than that of the conductors.

Abstract: A keyboard has a space bar centrally mounted on a plunger and supported at its ends by a torsion rod. The torsion rod has crank arms at its ends which are connected to the space bar and serve to distribute the actuating force on the space bar so that the plunger will move smoothly up and down and not bind. An attachment element in the nature of a yoke is provided for connecting the crank arms of the torsion rod to the space bar. A spring connected to the space bar flexibly engages the crank arm. The attachment element accommodates the natural, arcuate motion of the crank arm while simultaneously maintaining engagement with the crank arm to secure the space bar to the torsion rod and prevent the space bar from rattling or vibrating.

Abstract: An electrical component attachment for securing discrete components to a rigid circuit board without the use of plated-through holes. A unitary sheet member has a membrane portion and a flap portion. The membrane portion lies on one side of the circuit board. The flap portion wraps around an edge of the circuit board and is adhesively secured to the other side of the board. An electrical component is disposed between the flap portion and the board so as to be secured thereto by the flap portion. The sheet has conductive traces which contact the leads of the electrical component, providing electrical connection thereto. The sheet may have a tail onto which the traces extend for connection to external circuitry.

Abstract: A sealed rotary switch has electrical contacts insert-molded in a stator. The stator has generally open ends which are closed by a pair of covers. The joint between the covers and the stator includes a notch filled with adhesive sealant. The covers have aligned openings in which a rotor is mounted for rotation. Each cover has a seat formed around its opening, with a resilient seal member located in the seat and sealing against the rotor.

Abstract: A keyboard switch assembly includes a membrane switch matrix formed on a baseplate. There are a plurality of individual pressure applicators or keys which are mounted on the baseplate in a keyboard array. The keys are supported adjacent the membrane switch panel with each key being used to effect contact closure at a particular area of the membrane switch. Each key includes a movable plunger, a housing to support the plunger, a first coil spring biasing the plunger away from the membrane switch and a keytop affixed to the plunger. A second coil spring is seated upon the membrane switch matrix and provides the means for application of electrical contact closure pressure. Each key housing includes an enclosure which is accessible from the top of the housing. The closure is adapted to receive and retain a cam follower which controls movement of the plunger. The key housings further include a hook which can support a torsion rod.

Abstract: A coding and decoding system for video signals includes means at the transmitter for applying sine wave amplitude modulation of approximate line frequency to the aural carrier to prevent the chrominance subcarrier from providing receiver synchronization.

Abstract: A membrane switch has a substrate and a plurality of first conductors formed on the substrate. A flexible membrane having a plurality of second conductors formed thereon is positioned relative to the substrate by a spacer which may be adhesively secured to both membrane and substrate. There are openings in the spacer in register with aligned first and second conductors. The membrane is caused to move toward the substrate through an opening to cause contact between the aligned first and second conductors in response to pressure upon the exterior of the membrane. There are vent passage means interconnecting the spacer openings, which vent passage means may be open to the atmosphere.