Abstract: A feed-forward amplifier utilizes frequency dependent delay elements to cancel the effects of phase dispersion in the amplifier to amplify a broadband, high-frequency signal with low distortion.

Abstract: Disclosed is a method for removing a layer of tin or tin-lead alloy from a copper substrate of a printed circuit board employing the two different reagents in a two-step procedure without damaging the substrate, and at the same time, preventing formation of whitish precipitates in the treating solution.In the first step, the layer of tin or tin-lead alloy is selectively removed with the first reagent having a comparatively mild oxidation capability, then in the second step the intermetallic layer consisting of tin and copper is removed with the second reagent having a comparatively strong oxidation capability.This process ensures a smooth and effective operation in the production of high quality printed circuit boards.

Abstract: A process for printing the flat top lines of a corrugated paper board in a single pass by a sheet of the board through a top printing rotary letter press printing press and then through a varnishing equipment while the ink is still wet. The sheet having the wet ink and varnish coatings is dried under an infrared heater while forcibly holding it flat against warping.

Abstract: A coiled spring making apparatus is provided, including a coiling section for forming coiled springs and a progressive forming section for progressively feeding the coiled springs formed at the coiling section to a plurality of stages on which the coiled springs are held and successively formed into the desired shape. The coiling section is of a bending die system of coiling section at which the coiled springs are formed with their axes kept vertical, and is mounted on a movable table which is movable to any position horizontally or transversely with respect to the progressive forming section and fixed there.

Abstract: The device includes at least one selection lever, one end whereof is arranged laterally facing the needle cylinder at the level of a heel of selection elements accommodated in the grooves of the needle cylinder below the selectors or sub-needles. The selection lever is movable towards or away from the needle cylinder from a first position, in which its end engages the heel of the selection elements, to a second position in which it does not interfere with said heel. The end of the selection lever has a rising portion which in the first position raises the selection element when the needle cylinder rotates with respect to the selection lever. As an effect of this lifting, the overlying selector is engaged by a lifting cam arranged facing the needle cylinder so that the overlying needle is moved to knit.

Abstract: This knitting machines includes a device for adjusting the stitch density and for offsetting the stitch cam with respect to adjacent knitting cams. The device comprises a stitch cam associated with a knitting cam supporting structure which is arranged facing a needle supporting element and is movable relatively thereto actuate the needles by means of the knitting cams. The stitch cam is controllably movable relatively to the knitting cam supporting structure along a direction which is substantially parallel to the axis of the engaged needles. The stitch cam is furthermore controllably movable relatiely to the knitting cam supporting structure along a direction which is substantially parallel to the tangent to the path of the knitting cam supporting structure in the motion relative to the needle supporting element to anticipate or delay the engagement of the stitch cam with the needles.

Abstract: This device for tensioning knitted fabric in a circular knitting machine. In particular of the large-diameter type, comprises a plurality of tensioning rollers arranged with their respective axes in succession along a broken line inscribed in a circumference which is concentric to the machine; the tensioning roller co-operate with presser counter-rollers to retain the knitted fabric, and actuation elements act on the tensioning rollers and rotate them to tension the knitted fabric while it is being formed. The actuation elements are constituted by hydraulic motors, each motor being arranged inside a respective one of the tensioning rollers and acting on the roller to controllably rotate it about its axis.

Abstract: A MMIC variable slope gain-equalizer varies the conductance of depletion mode Schottky gate FETs to controllably insert frequency dependent resonant members in a modified bridged-T configuration. Resistors connected from circuit input port to output port define the arms of the "T" and a T-node to which a first frequency dependent resonant member is connected in series with a first FET. A second FET and a second frequency dependent resonant member are each connected in series between the circuit ports, bridging the T. Preferably a third frequency dependent resonant member is series connected with the second frequency dependent member. Each frequency dependent resonant member resonates at about the highest frequency of interest, typically about 18 GHz. When the first FET is on and the second FET off, maximum attenuation at lower frequencies is inserted into the circuit, and when the first FET is off and the second FET on, minimum attenuation is inserted at lower frequencies.

Abstract: An improved method for assembling a travelling wave tube (TWT) including the step of forming a heat stripe along the barrel of the TWT to reduce the diameter of the barrel and create an interference fit between the barrel and internal components of the TWT.

Abstract: A token collecting safe (10) is described, which includes a parallelepipedal box that is provided with a fixed cover (15), including an upper cavity of semicircular shape (16) with handle (17), a rectangular opening with a recess (18) usually closed by means of sealing wax or a transparent sight-hole (20), an upper opening or device for token input (22) for token access to an upper token collecting trough (23) and a second token input device (24) for token access to a lateral token collecting trough (25). The token collecting troughs (23, 25) are built from a plastic material and are provided with slots (28, 31) in their respective free ends to ensure the irreversible fall of the telephone tokens into the safe.

Abstract: A MMIC variable att4enuator uses depletion mode Schottky gate FETS as variable conductance devices in a ".pi." configuration to vary attenuation as a function of a DC control voltage. Attenuation is flat within .+-.1 dB, VSWR is .ltoreq.2:1 throughout the operating frequency and control voltage range, and about 12 dB variable attenuation is provided. The ".pi." is formed by FETs in shunt to ground between attenuator input and output, and by a FET in series between input and output. Resistors and an inductor connected in parallel with the series FET extend attenuator bandwidth to 20 GHZ and improve attenuation linearity versus control voltage. A resistor in series with each shunt FET also improves linearity. The typically 0 to +3 VDC control voltage is applied to the FET gates and drain/source leads permitting attenuation control with a single control voltage.

Abstract: The process has: a first step of formation of an elastic border, a second step of formation of a tubular body of knitting starting from the elastic border for a preset number of complete rows, a third step in which a first group of needles and a second group of needles of the machine, which operate on mutually angularly spaced portions of the tubular body, are excluded from working to define a pair of missing portions which constitute the leg apertures of the briefs; the needles excluded from working gradually increase in number for a widening of the missing portions. In the second step, during the knitting of the last complete rows of the tubular body, a preset number of needles, which operate in the mutually angularly spaced regions, and, in the third step, a preset number of needles proximate to the first group and to the second group of needles, are fed with yarn and with elastic thread for the formation of an elastic border around the leg apertures.

Abstract: This device for the selection of the needles comprises a selector accommodated below a needle in a same groove of a needle bed of the machine. The selector is controllably movable from an extraction position, in which a heel thereof protrudes from the groove to engage with selection cams facing said needle bed, to a sunk position, in which the heel is accommodated in the groove so as to not engage with the selection cams. Between the selector and the bottom of the groove an elastic element is interposed which keeps the selector in the extraction position and a sinking cam is provided, rigidly associated with the selection cams, which causes the passage of the selector from the extraction position to the sunk position in contrast with the elastic element. A rod is engageable with the elastic element to keep the selector in the sunk position and actuators controllably act on the rod to cause disengagement thereof from the elastic element so as to obtain the passage of the selector to the extraction position.

Abstract: A spindle for working chairs having an adjustable height comprises an inner tube (1) which is slidably inserted in an outer tube (3) and extends therefrom and is adapted to transmit the load from the chair seat to the outer tube. The inner tube (1, 1', 1") is lockable in a plurality of positions relative to the outer tube. The load is transmitted from the inner to the outer tube through a threaded spindle (10, 10', 10") which is coaxial with the tubes and is rotatably mounted in the outer tube (3), and the threads of which engage a nut (8) which is stationary with respect to the inner tube. The threaded connection formed between the nut and the spindle has a pitch which is sufficiently large for the connection not be self-locking when the nut (8) is moved axially, but still sufficiently small to allow a substantial part of the axial load to be transfered to the threaded spindle (10, 10', 10").

Abstract: An electric wire having an insulating core rope made of aromatic polyamide fiber, an electric insulating intermediate layer of high heat resistant material which covers the electrical insulating core and an outer conductor which surrounds the intermediate core and is composed of wound conductive wires, elongated conductive pieces or a single bent plate. A pipe which may contain an optical fiber may be embedded in the core and the insulating core may include a heat generator located therein.

Abstract: A method of cladding a steel roll, such as a felt roll with a non-corrosive shell, ensures that the shell is tightly fitted to the core and is free to expand and contract on the core to avoid distortion problems. The method comprises the steps of preparing two stainless steel shells each having a length equivalent to the circumference of the core plus a predetermined extra, wrapping the shells about the core, side by side, leaving a predetermined circumferential gap between the shells, heating and clamping the shells tightly around the core until the longitudinal joints each attain a predetermined longitudinal gap, welding the longitudinal gaps, and circumferential gap between the shells while the shells are hot, ensuring the sheets are welded together and not welded to the core.

Abstract: This device for supporting cops in circular knitting machines, particularly in fixed needle cylinder knitting machines, comprises a plurality of frames which are arranged close together around the machine axis and carry the machine feed cops. Each frame is translatable parallel to itself along a direction having a substantially parallel component to the machine axis from a first raised working position to a second depressed position away from the machine axis to enable a floor-based operator to get at the cops of one frame when the latter occupies the second position; the device also comprises hooks for locking the frames in the first position.

Abstract: The device is provided with electric signal emitting members associated with one machine portion, electric signal receiving members associated with another machine portion, a first and second optical fiber element respectively attached to a first and second stationary machine portion, a third and fourth optical fiber element attached to a rotating machine portion included between the first and second stationary machine portion. The ends of the first and second optical fiber element mutually face respective ends of the third and fourth optical fiber elements, the ends thereof laying coaxial with the axis of the rotating machine portion and the first and third optical fiber elements being autonomous from the second and fourth optical fiber elements for contemporaneously transmitting different signals having different frequencies from one of the machine portion to the other.

Abstract: The device comprises a small plate elastically flexible, longitudinally flanked by a needle for plain knitting, or purl knitting, and movable in a direction longitudinal with respect to it. The needle has on one of its sides an inclined area with which at least one inclined area engages, defined by a bend of the small plate at the moment of its motion relatively to the needle. In this manner an elastic flexing of the small plate is obtained moving away from the needle which defines a loop within which a needle for purl or plain knitting can be inserted, in order to transfer a loop of knitting retained around the loop.