Abstract: In the plating of wire, particularly gold plating of wire for terminal pins, obtaining a high quality fixed gold plate is a problem. The invention provides for testing the wire prior to plating to detect surface irregularities which affect the quality of the plate. A test length of wire has a length of tape wrapped spirally around, with at least an edge portion in contact with the wire. The wire, and tape, is then twisted, in the direction of the spiral of the tape, in a direction to tighten the tape. The tape is then unwound and the number of particles of wire material which have separated from the wire at defects adhere to the tape is counted. For premium grade wire, less than 6 defects per foot is a standard. Commercial grade wire, between 50 and 150 defects per foot is normal.

Abstract: A distributing frame, for telecommunications systems, comprises an upright hollow member, on the front of which are mounted a number of shelf members, spaced vertically, one above the other. Modules, containing connectors are mounted on the fronts of the shelf members, usually in pairs, a pair on each shelf member, the modules side-by-side. Further modules are mounted on the back of the hollow member, again usually in vertically spaced pairs. Access to the modules is provided from the interior of the hollow member. A number of such frames can be mounted side-by-side and the tops of the shelf members form continuous shelves for carrying conductors. In an arrangement of a plurality of frames side-by-side, the front is referred to as the horizontal side, while the back is referred to as the vertical side.

Abstract: An enclosure for electrical equipment is arranged in sections, typically vertical and with an equipment mounting section at the front and an air passage section at the rear. Air is constantly circulated through the two sections, in a closed loop, to maintain an even temperature and avoid hotspots in the enclosure. At the top, one or more fans are positioned over each section, and an air inlet and an air outlet are provided. A pivotal baffle has two positions. In one it shuts off access to the inlet and outlet and permits the closed circulation of air. In the other position it shuts off circulation between sections at one end and opens access to the inlet and outlet, giving an air circulation from the inlet, through the sections and out of the outlet. An additional fan can be switched on for the latter form of circulation.

Abstract: In the testing of dry circuit contacts, a constant current source is applied to the contacts. The open circuit voltage of the source is set to a predetermined maximum value and then the short circuit current at the contacts measured. If the current value is below a predetermined maximum value, the voltage of the source is increased to bring the short-circuit current to the predetermined value. The voltage drop across the contacts is then measured and the contact resistance calculated. This arrangement makes adjustments to take into account variations in the test circuit, such as different lead lengths and other variables, without subjecting the contacts at any time to an open circuit voltage or short circuit current above maximum values.

Abstract: A packaged optical fiber splice is held in a retainer formed by two pairs of cantilever members having inwardly facing ribs at their top edges. The members of a pair are spaced so that after pushing a packaged splice between the ribs, deforming the members slightly, the packaged splice is freely positioned between the cantilever members which are at least substantially stress free. The splice is retained by the ribs. A slot in the base of the retainer provides a seating for the lower edge of the splice and restrains the splice against longitudinal movement. A plurality of retainers are provided in an organizing tray.

Abstract: An overload protector for a telephone set or other telecommunications terminal comprises an electrical component having DC continuity and DC resistance mounted by leads on a circuit board, the leads soldered to the conductor pattern. A compression spring is positioned on each lead, held in compression between component and circuit board. An insulating member fits around the component. In application of an overload, the component heats up to a level at which sufficient heat travels down the leads to melt the solder. Usually both leads become unsoldered. A convenient component is a carbon block resistor, in the Tip or Ring line. The insulating member would be a sleeve loosely fitting over the resistor and retaining heat in the resistor.

Abstract: A lead frame with parallel side members and parallel transverse members defining chip receiving areas along the frame, has a chip pad at each area. A support lead extends from each corner of the chip pad to corresponding conjunctions of side and transverse members. A U-shaped support bar extends between each adjacent pair of support leads, each support bar including spaced parallel leg portions connected at inner ends to the support leads and at the outer ends by a lead support portion. Leads extend from each lead support portion towards the chip pad. By this means the chip can be assembled to the pad and wire bonding between chip and leads carried out and the leads can be preformed or not, as desired, prior to encapsulation. After encapsulation, the lead support portions can be trimmed off but the encapsulated device is still held in the lead frame but the leads are electrically isolated from each other. Testing can be carried out while devices are still in the lead frame.

Abstract: A lockable band clamp, such as clamping together the rims of a housing and a base of an equipment housing, has a flexible band with Vee-shaped portions for positioning around the rims, the rims positioned in the Vee-shaped portions. The ends of the band have end members through which passes a bolt, a tubular member threading on to the bolt. Relative rotation between bolt and tubular member acts to pull the end members together and tighten the band about the rims. The end members have projections which overlap. A locking member which, in a locked position, engages at one end over a rod through the tubular member and at the other end aligns with holes in the projections whereby a padlock can pass through the holes and a formation on the locking member, preventing relative rotation between bolt and tubular member.

Abstract: In the production of coatings on semiconductor wafers, fragile equipment is used and also difficulties in obtaining uniform coatings arise. The invention provides a form of boat for holding wafers and a manifold structure for feeding gases to the boats, and wafers which are less fragile cheaper and easier to manufacture and give more uniform coatings. The boats are relatively short, of semi-cylindrical form with slots through which gas can flow, and with rails for positioning and holding wafers at correct heights. The manifolds have apertures which are spaced at varying distances along the manifold as compared to the conventional longitudinal slot. The invention is particularly applicable to producing oxide coatings and polycrystalline silicon coatings on silicon wafers.

Abstract: A rotatable latch, as for the door of an enclosure, has a positive indication of latching, the indication capable of being felt and heard. A rotatable latch member mounted, for example, on the door, has a radially extending finger which engages with a latch plate mounted on the door frame. The latch plate has an inclined surface up which moves the finger, against a spring bias. At the end of the inclined surface is a detent into which the finger snaps, under the action of the spring bias, when the rotatable latch member is in a fully latched position. The snapping of the finger into the detent can be both felt and heard.

Abstract: A termination tool for holding cross-connect connectors, as used in telecommunications systems, while inserting conductors into the back edge of the connector, is adapted to be releasably mounted on the support member on to which the connectors are eventually mounted. The tool, of open frame form, having spaced sides, back member and a rotatable front member, has formations at the back ends of the side members which engage with the support member. A connector is inserted in a slot extending along the front member with a back edge facing forward. The conductors can be inserted, a retainer snapped over the back edge of the connector, the rotatable member rotated approximately 90.degree. to bring the back edge of the connector and the retainer facing upwards, and then the connector and retainer removed from the tool and mounted on the support member.

Abstract: A surface mounting electronic component is provided with a layer of solder attached to each end of the component. Preferably the solder is flux cored. By this means deposition of solder paste on printed circuit boards and similar members is avoided, and high quality solder joints obtained.

Abstract: A handset for a telephone set is provided with a receive amplifier which is compatible with both electronic and electro-mechanical telephones, that is telephones having electro-mechanical transmitters and telephones having electronic transmitters. The operational amplifier is powered from the telephone line, from the power input to the telephone network, and is driven via an impedance matching circuit exhibiting a low AC impedance and having a capacitor to short out AC signals such as voice signals on the telephone line and a special transistor which has high AC impedance and low DC resistance to block out AC signals and provide DC power. The operational amplifier is of special characteristics, stabilized to work down to very low voltages, e.g. 1.1 volts and also capable of operating at higher voltages, e.g. 20 volts.

Abstract: An adjustable mounting for supporting one body, such as a visual display unit, relative to another, such as a console, has a plunger attached to one of the bodies. The plunger extends into a chamber in a part of, or secured to, the other body and is frictionally located in the chamber, specifically by a collet of synthetic plastics material. In a preferred mounting arrangement for a visual display unit, the visual display unit is pivotally interconnected to a support at a position which is spaced from the longitudinal axis of the plunger towards the display screen of the unit. Then extension and retraction of the plunger tilt the display screen relative to the viewing axis. The plunger is preferably spring-loaded to compensate for increased loading on the plunger due to displacement of the center of gravity of the visual display unit as the unit tilts.

Abstract: A combined pushbutton and lamp for a telephone dial has two housings connected together to form an enclosure for a lamp and a switch. A pivoted pushbutton is mounted on the housings, with a center part over the lamp, pivot members on one side of the center part fitting on pivots or one of the housings and a lever extending on the other side of the center part and actuating the switch. A bezel member snaps over the center part of the pushbutton and holds it assembled to the housings. The lamp extends up into the center part of the pushbutton which has restricted movement, the lever amplifying this movement to actuate the switch.

Abstract: Secondary surge protection means for equipment connected to transmission lines, for example line-powered amplifiers interconnecting T1 or T1C telephone lines, includes two diode bridges and a pair of surge diverters. One diode bridge has its cathode/anode nodes connected one to each conductor of an incoming transmission line. The other diode bridge is connected in like manner to an outgoing transmission line. Each surge diverter interconnects the anode/anode node of one bridge and the cathode/cathode node of the other bridge. When a surge on one line causes the voltage across one or other diverter to exceed a predetermined threshold, the diverter conducts, shunting the surge past the amplifier to dissipate in the other line. The two transmission lines may be coupled to the input and output, respectively, of one amplifier, or to the input of one amplifier and the output of a different, oppositely connected amplifier.