Abstract: Impedance tuners used in high power measurements suffer fast heating and consequently thermal expansion of the center conductor, which has a very small mass and is thermally isolated from the environment and tuner housing. This leads to false measurements or catastrophic tuner failure (short) of either the DUT or the tuner. Modified center conductors are made of two pieces and comprise a flexible joint between them that allows longitudinal center conductor expansion and contraction, thus preserving tuner accuracy and safety. Practical tests have shown significant improvement in thermal behavior.

Abstract: A tunable filter wherein coupling sections (51, 52, 53) are formed in an input/output line along its lengthwise direction, each coupling section including a gap (G51, G52, G53) formed in the input/output line and coupling electrodes (E5a1, E5b1, E5c1) arranged in the gap in the longitudinal direction of the input/output line; and resonators (41, 42) capable of varying the resonance frequency are connected to the input/output line at the positions between adjacent ones of the coupling sections. Switch means (71, 72, 73) are provided for selectively grounding the coupling electrodes of the coupling sections or selectively short-circuiting the coupling electrodes and the input/output line, and resonance frequency varying means (4m1, 4m2) are provided for varying the resonance frequency of the one or more resonators in association with the switch means.

Abstract: A microwave applicator for heating loads being a waveguide transition between the rectangular TE10 and TE20 modes comprising a TE10 mode section and a TE20 mode section. The location of the load being inside said TE20 mode section and with its major axis perpendicularly to the major propagation direction of the TE20 mode, close to a shorting wall of said TE20 mode section and also close to the centreline of said propagation direction.

Abstract: An enhanced tunable coaxial cavity filter that may be tuned while it is shorted. The coaxial cavity filter may have one or more cavities. One or more of the cavities may include a switch for shorting the cavity. When a plurality of cavities are implemented, the cavities may be coupled in series such that shorting one of the cavities effectively shorts the entire filter. The switch for shorting the cavity may include a solenoid switch. The solenoid switch may be disposed within a stator that is stationary with respect to a rotatable rod for tuning the filter. Such a design has shown to be extremely robust for wear, vibration, and other considerations, even in high stress environments.

Abstract: An EMP-eliminator is to be created which is simultaneously applicable for multiple frequency bands and highest frequencies and at the same time allows transmission of AC/DC supply voltages. For this purpose a casing (20) set in an outer line (10) is provided as well as a line (24) connected in an electrically conductive manner to an inner line of a coaxial line (30). The line (24) is connected in an electrically conductive manner with the equipment casing (20) or its face side via a gas filled overvoltage suppressor (28). The gas eliminator (28) is set into a threaded cover and thus can be exchanged. Between the equipment casing (20) and the line (24) several bushes (25,26) connected electrically to the line are provided. The length of the line (24) corresponds to the .lambda./4 length of the lowest transmitted frequency band. Several serially connected resonant cavities result which are matched in their length to different midband frequencies.

Abstract: A coaxial resonance cavity of either the fingered or unfingered variety having a metal heat conducting barbell shaped structure inside the movable tuning plunger to conduct heat from the inner surface of the movable plunger to the inner surface of the fixed stub or directly to the shield to provide for a heat conductive path to the shield to carry heat away from the inner plunger. The barbell is an integral structure machined from stock aluminum, but resembles three right circular cylinders butting end to circular end. The upper cylinder has a diameter appropriate to maintain tight contact with the stub. The lower cylinder has a smaller diameter, appropriate to maintain contact with the movable plunger.

Abstract: A coaxial short-circuit device has an inner conductor which is surrounded by an outer conductor and is electrically connected to the latter by a shorting plunger. In order to allow the axial movement of the shorting plunger, the inner conductor accommodates a spindle which is connected in a force-locking manner to a first carriage arranged between the spindle and the inner conductor. A second carriage is arranged between the inner and the outer conductor and cooperates with the first carriage in such a manner that upon rotational movement of the spindle the first carriage is axially shifted along the spindle and this movement is transmitted to the second carriage and eventually to the shorting plunger which is connected to the second carriage in a force-locking manner.

Abstract: Coaxial filter having at least one of the internal and external conductors which is divided into sections (S.sub.1 to S.sub.4) separated by breaks having to form of annular slits whose thickness is very slight in relation to the wavelength.Each section comprises at least one reactive tuning element such as an open or short-circuited coaxial line portion and at least one switch element located in the vicinity of the corresponding break in order selectivity to short-circuit the said break or bring about the insertion of the corresponding reactive tuning element in response to electronic control devices.Application to telecommuncations.

Abstract: The resonator is formed with a primary line which is slightly less than a ltiple of a half wavelength long, a tee, and a matching stub. The primary line and the stub are adjustable to make the total length a multiple of one half wavelength. A mechanical link can be connected across the two adjustable lengths so as to maintain a total length of a multiple integral of one half wavelength.

Abstract: A coaxial resonator is provided having an outer conductor with top and bottom closures and a substantially central opening through the top closure through which a tubular member forming a center conductor extends. The center conductor also comprises a plunger which is moveable within the tubular member such that the electrical length of the center conductor can be varied to effect tuning of the resonator.The tubular member and the plunger are spaced apart in slidable relationship one with the other and as the bottom end of the tubular member represents essentially a short circuit, at that point there is no physical electrical contact provided between the tubular member and the plunger, thus overcoming several disadvantages of prior art resonators which utilized "finger" electrical contact at that point.