Showing papers on "Stub (electronics) published in 1988"

Microstrip/slotline transitions: modeling and experimental investigation

Abstract: An analysis of microstrip/slotline transitions is given using a network description through transmission-line models. Different transitions, such as transitions containing uniform and nonuniform lines as well as soldered and virtually shorted microstrip lines, are treated. Although a transition with a soldered microstrip short offers the largest bandwidth, optimal combinations of different microstrip and slot stub diameters can be found by modeling. In the case of a virtual short through an optimally chosen circular microstrip stub, the bandwidth is typically about 10% below the maximum achievable value of a soldered short. The validity of the modeling results is verified experimentally by measuring the transmission coefficient of a cascade of two transitions separated by a slotline in the frequency range from 1 to 16 GHz. For practical applications, design curves are given for 0.635-mm-thick alumina substrates. >

Plasma generation in electron cyclotron resonance

Abstract: Electron cyclotron resonance (ECR) is achieved in a source chamber of a size which is non-resonant with respect to propagation of the microwave power within the chamber. The microwaves are delivered into the chamber via a waveguide and window so that breakdown occurs initially only in a region in the vicinity of the window. A dielectric coupler between the waveguide and the window has a larger end and a smaller end and is filled with a dielectric material. The magnetic field generator for stimulation the electron resonance in the chamber includes a pair of conductive current carrying coils coaxial with each other and with an axis of the chamber, the coils being arranged in a Helmholtz configuration. The waveguide includes a microwave stub tuner for tuning the propagation and absorption of the microwave power in the plasma within the chamber to control the location and shape of the region in which the plasma is formed. A conduit provides a path for delivery of the plasma from one end of the chamber and is sized to be non-resonant with respect to propagation of the microwave energy. The magnetic field is controlled to cause the formation of the plasma with high absorption of microwave power occurring substantially within a columnar region centered on an axis of the chamber. The chamber has an insulative lining.

Method for bonding an article projection

Abstract: A method for repairing or manufacturing an article, such as a bladed disk, having an integral projection, for example an airfoil, includes first removing a damaged projection to provide a stub, or in new manufacture providing the stub. A collar shaped to register with the stub is provided and bonded to the stub to generate a stub-collar combination. Then a replacement or new projection member is bonded to the stub-collar combination. Finishing then provides the article. Apparatus includes the combination of a metal attachment die and a heating means retained in a recess of the die during bonding.

Optimum design of waveguide E-plane stub-loaded phase shifters

Abstract: Broadband low-insertion-loss E-plane stub-loaded rectangular waveguide phase shifters are designed with the method of field expansion into normalized eigenmodes, which includes higher-order mode interaction between the step discontinuities. Computer-optimized three-stub prototypes of 90 degrees differential phase shift with reference to an empty waveguide of appropriate length, designed for R140-band (12.4-18 GHz) and R320-band (26.5-40 GHz) waveguides, achieve typically +or-0.5 degrees phase shift deviation within about 20% bandwidth. For two-stub designs, the corresponding values are about +2.5 degrees /-1 degrees and 17%. Both designs achieve minimum return loss of 30 dB. The theory is verified by measurements of a compact R120-band (10-15 GHz) waveguide phase shifter design example milled from a solid block, showing measured insertion loss of about 0.1 dB and about +2.5 degrees /-0.5 degrees phase error between 10.7 and 12.7 GHz. >

Volume compensated fluid mount

Abstract: A fluid mount particularly suited for mounting an engine (E) in an aircraft. The mount includes a frame (20) which is fastened to the engine (E) and a support (30) movably mounted in the frame and adapted to receive a wing pylon stub shaft (10). Opposed liquid-filled chambers (40, 41) are provided on opposite sides of the stub shaft support (30) and are fluidly inter­connected by an elongate tube (45). An auxiliary chamber (50) is provided on the frame adjacent to the upper liquid chamber (40) and is divided internally into a gas-filled portion (54) and a liquid-filled portion (51) which is in communication with the upper liquid chamber via an orifice (52). The auxiliary chamber (50) accommodates changes in liquid volume without adversely affecting either the static or dynamic performance of the mount.

Wheel bearing assembly

Abstract: A wheel bearing assembly comprises an outer bearing member which is secured to a steering knuckle, and a hollow spindle which is rotatably supported in a fixed longitudinal relationship in the outer bearing member by two rows of bearing balls. The hollow spindle has a splined bore which receives a splined stub shaft of a drive bell which is pulled through the splined bore by way of a pull groove in the free end of the stub shaft. A snap ring is assembled to the stub shaft to secure the hollow spindle on the stub shaft against the resistance of a deformed crush ring which is disposed between an inboard end of the hollow spindle and a shoulder of the drive bell. In an alternate embodiment the snap ring secures the hollow spindle on the stub shaft against the resistance of interengaging straight and helical spines of the hollow spindle and the stub shaft.

Equivalent circuit modeling of losses and dispersion in single and coupled lines for microwave and millimeter-wave integrated circuits

Abstract: Losses and dispersion in open inhomogeneous guided-wave structures such as microstrips and other planar structures at microwave and millimeter-wave frequencies and in MMICs (monolithic microwave integrated circuits) have been modeled with circuits consisting of ideal lumped elements and lossless TEM (transverse electromagnetic) lines. It is shown that, given a propagation structure for which numerical techniques to compute the propagation characteristics are available, an equivalent circuit whose terminal frequency and time-domain properties are the same as the structure can be synthesized. This is accomplished by equating the network functions of the given single or coupled line multiport with that of the model and extracting all the parameters of the equivalent circuit model by using standard parameters identification procedures. This model is valid over a desired frequency range and can be used to help design both analog and digital circuits consisting of these structures and other active and passive elements utilizing standard CAD (computer-aided design) programs. To validate the accuracy and usefulness of the models, results for a mismatched 50- Omega line in alumina and a high-impedance MMIC line stub are included. >

Adjustable stub guard assembly for corp cutting apparatus

Abstract: The adjustment between the stub guards of a sickle knife arrangement of a crop cutting apparatus is improved by the provision of an adjustment plate which is positioned between the upper stub guard and the support bar. The upper and lower stub guards are clamped onto the support bar by carriage bolts with the lower stub guard engaging against the under surface of the support bar and the upper stub guard engaging against the upper surface of the adjustment plate. The spacing and orientation of the adjustment plate relative to the support bar is adjusted by the three set screws which are threaded into the adjustment plate and engaged against the upper surface of the support bar. The adjustment technique is simple, requires few parts and avoids the necessity for shims.

Apparatus for detecting and locating leakage in underwater structures

Abstract: A system for leak detection in underwater structures wherein each critical leakage test point is maintained dry by an enclosure and a test cable is led down through the series of enclosures in fluid-tight manner to support a test probe within the dry test point volume. The test cable is a coaxial cable of selected characteristic impedance and each probe consists of a spirally wound, open-end dual pair supported on a plastic stub so as to constitute a parallel resonant circuit at a selected frequency. Thereafter, a test pulse is conducted down the coaxial cable and the impedance of any probe will be altered by the presence of water to produce a reflected pulse back up the coaxial cable to be detected and input to gating and counting circuitry to determine signal travel duration and, therefore, distance along the cable, as processing, printing and readout components provide output indications.

Rotary electrical machines

Abstract: A synchronous alternating current machine having a superconducting field winding on a hollow cylindrical portion of a rotor which is joined by hollow frustoconical transition members to supporting stub shafts. The field winding is cooled by cryogenic fluid from a refrigerator, which may be wholly or partly within the rotor, and heat leak into the winding is minimized by the hollow transition members, which are themselves cooled, and a radiation shield mounted on the outside of the rotor.

Model for multimode picosecond dynamic laser chirp based on transmission line laser model

Abstract: Laser chirp contributes significantly to the linewidth of near single-mode injection modulated semiconductor laser devices, and is a consequence of the carrier dependence of the active layer's refractive index. A model is developed that can accurately predict the multimode chirped spectra of Fabry-Perot devices based on the transmission line laser model (TLLM), with the addition of a transmission line stub and attenuator to the end facets. This time-domain model is easily interfaced to both drive circuit and fibre impulse response models. A 1550 nm InGaAsP device model under picosecond modulation is tested against experimental and analytical results of other workers.

CAD-oriented lossy models for radial stubs

Abstract: A lumped equivalent circuit model for both series and double-shunt (butterfly) connected radial stub has been developed. The model-simple and effective-not only includes conductor and dielectric losses but also radiation ones, which play an important role in microstrip circuit elements. Experiments widely demonstrate its suitability for implementation in available CAD (computer-aided design) programs. Furthermore, a synthesis procedure for using radial stubs in circuit design is described. An application of the proposed design procedure and simulation tools in the development of very broadband nongrounded termination is also presented. >

Measurement of integrated tuning elements for SIS mixes with a Fourier transform spectrometer

Abstract: Planar lithographed quasioptical mixers can profit from the use of integrated tuning elements to improve the coupling between the antenna and the SIS mixer junctions. We have used a Fourier transform spectrometer with an Hg-arc lamp source as an RF sweeper to measure the frequency response of such integrated tuning elements. The SIS junction connected to the tuning element served as the direct detector for the spectrometer. This relatively quick, easy experiment can give enough information over a broad range of millimeter and submillimeter wavelengths to test both design concepts and success in fabrication. One type of tuning element, an inductive wire connected in parallel with a series array of 5 SIS junctions across the terminals of a bow-tie antenna, shows a resonant response peak at 100 GHz with a 30% bandwidth. This result is in excellent agreement with theoretical calculations based on a simple L-C circuit. It also agrees very well with the RF frequency dependence of the mixer gain measured using the same structure. The other type of tuning element, an open-circuited stub connected in parallel with a single SIS junction across the terminals of a bow-tie antenna, exhibits multiple resonances at 110, 220, and 336 GHz, with bandwidths of 9–15 GHz. This result is in good agreement with theoretical calculations based on an open-circuited stub with small loss and small dispersion. The position and the bandwidth of the resonance at 110 GHz also agrees with the RF frequency dependence of the mixer gain measured using similar structures.

Lock-up clutch

Abstract: A torque transmitting arrangement, for example an hydraulic torque converter of a vehicle transmission assembly, incorporates a direct coupling or lock-up clutch and comprises a fluid coupling (1) including torque input means to an impeller (2) and torque output means from a turbine (7). The lock-up clutch (17) comprises a clutch friction plate (19) including a friction member (20) which is engageable directly or indirectly with one of the torque input means and the torque output means. The clutch further comprises a first linking element such as a triangular weight (23) pivotally connected to the other of the torque input means and the torque output means by a stub (22), and a second linking element (25) pivotally connected to the clutch friction plate (19) by a stub (26) and to the first linking element (23). For a modification, the clutch directly engages the housing (3) and the stub (26) is mounted on the turbine (7). The linking elements and weights are stated to provide damping by two means.

Compact oil slinger and spring loaded retention device

Abstract: A quick connect apparatus (10) for attaching a stub shaft (14) to a main rotor shaft (16) of a generator. A rotatable retaining device (12) is secured to the end of the main rotor shaft (16) and includes channels (22) which are engaged by pins (30) projecting radially inward from an inner diameter portion of the stub shaft (14). A polgon drive portion (34) extends from the stub shaft (14) and engages a similar shaped polygon opening (18) formed in the end of the main rotor shaft (16) when the stub shaft (14) is attached. A biasing spring (40) is provided between the back of the polygon opening (18) and a recess in the mating polygon drive portion (34) for biasing the stub shaft (14) axially away from the main shaft (16).

Steering column coupling

Abstract: A steering column coupling for a motor vehicle has a pivoted link which swings onto a stub shaft from the steering gear. The link has one open side through which the shaft enters, and a captive bolt which can be slid along the link to close the open side once the shaft has been positioned.

Dual-Band Microstrip Antenna With Reactive Loading

Abstract: Effective but bulky coaxial stub replaced. Short-circuited microstrip transmission line serves as reactive loading element for microstrip antenna. Constructed integrally with stripline radiating element, shorted line preserves low microstrip profile and enables tuning of antenna for two-band operation.

Pressure vessel having a connection stub with a thermal protector

Abstract: A pressure vessel assembly includes a pressure vessel with a vessel wall having a connection stub with a stub wall. A thermal protector for the connection stub in the form of a first tube extends substantially parallel to the stub wall. The first tube has an inner surface, one end disposed at the stub wall and another free end extending into the pressure vessel. Brackets are disposed on the inner surface of the tube between the other free end and the stub wall. A second tube extends into the connection stub beyond the one end of the first tube. The second tube has slits formed therein defining prongs therebetween connected to the brackets.

Design procedure for inhomogeneous coupled line sections

Abstract: Design formulas are presented, along with a procedure for the design of inhomogeneous coupled line sections as an approximation to a series open-circuited stub for application in the realization of microwave pseudo-high-pass filters. The accuracy of the design equations is evaluated through the design and test of a seventh-order filter and it is found that the formulation predicts the performance of the section well beyond the quarter-wave frequency. >

Microwave filter design using radial line stubs

Abstract: The design of microwave filters using radial line stubs as reactive elements is investigated. To reduce the design complexity, a simplified model for radial line stub reactance versus frequency is first developed. This allows for an easy transition from the lowpass prototype to the desired planar circuit elements. The frequency-response characteristic of specific radial line stub filter is compared to ideal lumped-element equivalents, and also planar circuit realizations using more traditional straight transmission line elements. >

An SIS mixer for 85-116 GHz using inductively shunted edge-junctions

Abstract: A superconductor-insulator-superconductor (SIS) mixer is described that has a broadband integrated tuning structure. The mixer is tunable from 85-116 GHz, and a midband has a noise temperature of 6+or-6 K DSB (double-side-band) and unity DSB conversion gain. Referred to the mixer input flange, the receiver noise temperature is 9+or-6 K at midband. The integral tuning structure consists of a short two-wire transmission line stub with a quarter-wave superconducting transmission line as a DC and intermediate frequency (IF) block. Despite the relatively soft I-V curves of the two-junction arrays used in these mixers, low mixer noise temperature and conversion loss were achieved. >

Device for retaining cables, lines, hoses or the like

Abstract: A device for retaining cables, lines, hoses or the like, having a hollow-cylindrical assembly connection stub and a pressure screw which can be screw-connected thereto, exhibits, between connection stub and screws, a relatively steep multiple-start thread, by means of which it is possible to tighten the pressure screw by rotating it through a small angle.

Microwave automatic load matching circuit

Abstract: PURPOSE:To allow a load of a microwave band to reach an excellent matching state automatically in such a short time as within several seconds by employing two sets of composite stubs whose insertion length is varied continuously in a differential way CONSTITUTION:A detection circuit adopts five probes 61-65 to constitute a microwave automatic load matching circuit as shown in figure in combination with the two sets of composite stub matching devices 51, 52, and the circuit is operated with a traveling wave power of 5kw(at matching) in a frequency of 2450MHz, resulting that the load with the voltage standing wave ratio 10 (that is, 165kw reflecting power) is matched automatically into the reflecting power of<=50w within 3 sec In this matching state, the reflectin coefficient is 01 and the voltage standing wave ratio is<=122, that is a very excellent state In using said composite stub matching devices, since two adjusting parts exist and their characteristics are orthogonal over nearly the entire range, the automatic matching is easily and quickly applied

Friction member wear indicator for motor vehicle brake and friction member equipped with this wear indicator

Abstract: The indicator comprises an electrical conductor 2 embedded in a body 1 from which there extends a stub 3. A removable piece 17 is fixed at 18 onto a filiform part 1' of the indicator. In order to mount the indicator, the stub 3 is pushed into a hole 9 pierced in the support plate 5 for the friction member and the filiform part 1' is folded back around one edge 7 of the plate, in order to exhibit an opening 10' in the piece 17 facing the end of the stub 3. The groove formed at the end of the stub 3 makes it possible to retain the removable piece 17 against the support plate 5 in order to fix the indicator onto this plate. Application to disc brakes or drum brakes for motor vehicles.

Internally disposed welded binding

Abstract: A passbook is provided that substantially prevents alteration or counterfeiting. The passbook is formed from a plurality of sheets of flexible material that are bound to one another at selected locations thereon by welding to define a substantially integral stub. The free edges of the welded pages are then folded back over the welded stub such that the stub is disposed interiorly. The welded stub is difficult to disassemble and reassemble without providing some indication of tampering. Furthermore, the disposition of the welded stub enables the passbook to be laid flat without creating stresses on the stub that could result in separation or delamination.

An alternative approach for designing microwave circuits using a personal computer

Abstract: A computer-aided design (CAD) program, Puff, for designing microwave integrated circuits is presented. The program runs on an IBM PC, PS/2, or compatible computer, and features a single interactive-graphics screen which displays all aspects of the design. Circuit elements, such as transmission lines, coupled lines, and lumped elements, are selected from a parts list and drawn on the screen using cursor keys. The circuit analysis is then performed directly from the screen drawing. To demonstrate the various features of Puff, predictions for a 10-GHz patch antenna with a stub matching circuit are compared with measurements made with an HP 8510 network analyzer. >

Integrated amplifier circuit

Abstract: PURPOSE:To attain the application of the titled circuit to the component of a class F amplifier by making an output matching circuit in an integrated circuit package match with both the fundamental frequency and its 2nd order harmonic component CONSTITUTION:The output matching circuit 12 is provided with a fundamental wave matching stub circuit 31 and a 2nd order harmonic matching stub circuit 32 Moreover, the fundamental wave matching stub circuit 31 and the 2nd order harmonic matching stub circuit 32 are placed on a strip circuit with a proper distance In designing the length properly, the output impedance of an FET chip 22 is to be matched at two frequency points of the fundamental wave and its 2nd order harmonic component The level of the fundamental wave component and the 2nd order harmonic component in the output signal of the FET chip 22 is not lowered, and the signal is fed to an output terminal 17 of an IC package 21

Valve, particularly a water valve for motor vehicles

Abstract: The invention relates to a valve with an inlet stub, an outlet stub and a slide which can be actuated by means of a drive. To allow simple and unproblematic sealing and to ensure a low resistance to the flow of medium in the open condition, a hose is provided, and this hose connects the inlet stub and the outlet stub to one another. A web-like abutment, against which the hose rests, is also provided. The slide is in the form of a web and the hose can be compressed between the slide and the abutment.

Shaft connection for torque transmission

Abstract: A method of making a torque transmitting connection between a shaft (10) and a sleeve (16, 17, 18), by swaging the sleeve into engagement with a portion of the shaft provided with e.g. splines (12), wherein the sleeve is deformed firstly (at 15) into engagement with a locating formation between sets of spines (12) on the shaft to determine the relative axial position of shaft and sleeve during the rest of the swaging process. The invention improves the positional accuracy of the connection between the shaft and the sleeve. The swaging is carried out by dies which impact radially on the sleeve. The shaft (10) may be the stub shaft of a motor vehicle constant velocity ratio universal joint.

Torque sensor control circuit

Abstract: PURPOSE:To stop the assisting power from a motor at the time of the breakage of wire or short circuit by processing an output signal from a Hall element by a sensor output processing circuit and, then, sending said output signal to a microcomputer via a connector. CONSTITUTION:When a relative change takes place between a stub shaft 100 and a pinion shaft 40, a Hall element 70 and a magnet 80 make relative rotational displacement. Thereby, the magnetic field of the magnet 80 which acts on the Hall element 70 is changed causing a voltage outputted from the Hall element 70 to change. The output of the Hall element 70 is inputted into a signal processing circuit 72 which is fixed to the stub shaft 100 and amplified in the circuit 72 and outputted. This output signal is transmitted from ring plates 91 fixed to a ring base 76 integrally formed with the stub shaft 100 to a brush holder 93 side via a brush 92, and fed to a microcomputer by means of lead wires 94.