Abstract: A heat sink absorbs heat from a chip or other component (32) and transfers the heat to a cooling fluid (36). The sink has a shaped part (22?) on which are formed at least one element (56?) for supplying cooling fluid (36) and at least one element (62?) for removing cooling fluid (36). The heat sink has a heat absorber (68?) with a heat-absorption side (112u) that absorbs heat during operation and a heat-transfer side (78) in contact with the cooling fluid (36) during operation. The absorber has a depression (118) in which are arranged a plurality of elongated thermally conductive elements (84?) which are each connected at a first end to the depression (118), and each have a free end (78) projecting away from the depression (118). Optionally, the heat sink can be coupled to a radiating or cooling unit (38), a fluid-circulating pump (39) and a fan (40) for directing air over the cooling unit, in order to quickly dissipate the heat transferred to the cooling fluid (36).

Abstract: An indirect evaporative cooler includes a number of heat transfer plates. Each plate has a wet side and a dry side, and the dry sides of adjacent plates face each other. The plate dry sides have low permeability to an evaporative liquid. Input air flows over the dry sides from an input end to an output end. Part of the input air becomes product air and exits at the output end. The rest of the input air passes through perforations in the plates to the other side of the plates to become working air. The other side of each plate is a wet side, which is wet by an evaporative liquid. Working gas flows over the wet side, evaporating the evaporative liquid and cooling the evaporative liquid, the plate, and finally the product gas by heat transfer. The perforations are formed both toward the input end of the plate and toward the output end of the plate.

Abstract: The invention is an air conditioning unit 10 consisting of a housing 11 having at least one air inlet 21 for receiving air to be conditioned and at least one outlet 19 for discharging conditioned air, at least one fan 24 for moving air from the inlet 21 to the outlet 19, an air to air heat exchanger 26 of the type that cools the air by diverting and cooling a portion of the air through an evaporative cooling means, heat exchange occurring across a plurality of barriers 27 between the evaporatively cooled air and said incoming air, a vapour compression-type cooling system having an evaporator coil 54 through which the outlet stream of air passes for further cooling of the outlet air, a condenser coil 55 through which the evaporatively cooled air, stream that exits the air to air heat exchanger 26 passes, and a control system 60 that at least determines the temperature of the room 12 air and controls the operation of the air-conditioner to operate only the air to air heat exchanger 26 when the temperature is ma

Abstract: The present invention relates to a cold air guide structure of an ice-making chamber of a cold chamber door. The structure including: the cold chamber door; an insulation case disposed inside of the cold chamber door, thermally insulated and having an ice-making chamber therein; an ice-making unit installed in the ice-making chamber of the insulation case, for icing a supplied water by an ice-making cold air and housing pieces of ice; an insulation cover for opening and closing the ice-making chamber of the insulation case; a cold air inlet port for sucking the ice-making cold air into the ice-making chamber; a cold air outlet port for exhausting the ice-making cold air from the ice-making chamber; and an ice-making cold air guide unit for guiding the ice-making cold air to a predetermined air passage to suck or exhaust the ice-making cold air into or from the ice-making chamber.

Abstract: In the improved cooling system for a commercial aircraft galley, heat is transferred from a galley food cart by a point-of-use heat exchange system to a liquid cooled condenser. Liquid coolant for the liquid cooled condenser is circulated in a liquid coolant loop to a heat exchanger expelling heat for cooling the liquid coolant. The liquid coolant may be water or a mixture of water and glycol. A flow of cooling air from a heat exchanger cooled by the liquid cooled condenser is cycled through an air over system, through an air through system, or from a thermal convection air cooling system providing at least one cooled galley food cart surface to provide cooling. Heat may be transferred from a plurality of galley food carts to the circulating liquid coolant.

Abstract: This invention relates to a cooling device 10, 40 insertable into a container 402 to cool the contents 404 thereof, which cooling device 10, 40 includes at least one cooling body 12 defining a cavity in which a coolant can be stored and having coupling means 22 for releasably coupling the body 12 to an elongate rigid support element 24 having complementary coupling means 26 and by which the at least one cooling body 12 can be removable inserted into a said container 402. The invention extends to a kit 100 which includes a plurality of cooling devices 10, 40 and support means 102 for supporting the plurality of cooling devices 10, 40 in spaced relationship.

Abstract: A soft sided insulated container assembly includes a first portion having an insulated, soft sided external wall structure, and an internal, substantially rigid molded plastic receptacle mounted therein. It has a cover structure that includes a reinforcement member for engaging a land region of the molded receptacle, thereby tending to yield an interface tending to have a sealing relationship. The container may also include a thermal storage element, and the container may have an accommodation for receiving the thermal storage element.

Abstract: A liquid cooling system utilizing minimal size and volume enclosures, air pockets, compressible objects, and flexible objects is provided to protect against expansion of water-based solutions when frozen. In such a system, pipes, pumps, and heat exchangers are designed to prevent cracking of their enclosures and chambers. Also described are methods of preventing cracking in a liquid cooling system. In all these cases, the system must be designed to tolerate expansion when water is frozen.

Abstract: Hydrogen is liquefied by a process comprising pre-cooling hydrogen feed gas by indirect heat exchange against pressurized liquefied natural gas (“LNG”) to produce pre-cooled hydrogen feed gas and pressurized natural gas, further cooling at least a portion of said pre-cooled hydrogen feed gas by indirect heat exchange against at least one refrigerant to produce condensable hydrogen gas and expanding at least a portion of said condensable hydrogen gas to produce at least partially condensed hydrogen. One advantage of such a process is that the power consumed during liquefaction is significantly less than that consumed in existing hydrogen liquefaction processes which pre-cool hydrogen feed gas by indirect heat exchange against other refrigerants, e.g. liquid nitrogen.

Abstract: A process is described for liquefaction of a hydrocarbon-rich stream, especially a natural gas stream, at least indirect heat exchange taking place between the hydrocarbon-rich stream to be liquefied and the refrigerant mixture of at least one refrigerant mixture circuit, and the refrigerant mixture being separated after completed supercooling into a gaseous fraction and a liquid fraction and these fractions being recombined before and/or during the reheating of the refrigerant mixture. According to the invention, a gas fraction (9) that is identical or similar in composition is added at least from time to time to the gas fraction (4) that has been obtained in the separation (D). In doing so, the addition of the gas fraction (9) that is identical or similar in composition takes place when a minimum amount of the gas fraction (4) obtained in the separation (D) of the refrigerant mixture is not reached.

Abstract: Air is separated in a cryogenic distillation system operating a dual reboiler/condenser cycle. Refrigeration for the system is usually provided by expanding a process stream. In the present invention, refrigeration is provided by introducing from an external source at least one refrigerant.

Abstract: A new and improved magnetic structure comprises a linear form or array of a plurality of magnetic components that facilitates the relative disposition of such magnetic components with respect to each other whereby the plurality of magnetic components can be utilized to form any one of various different jewelry items, toys, amusement devices, educational implements, and instructional aids. The magnetic components are connected to each other along point-to-point contact loci, and spherically curved surface-to-surface contact loci, and a plurality of auxiliary or secondary ferromagnetic components may be magnetically connected to the magnetic components so as to define annular ring-like arrays around the point contact loci. The magnetic components can be identical in size, or alternatively, two alternating sets of magnetic components can have different diametrical dimensions.

Abstract: Twisting and flipping of a necklace along its length may be prevented by restricting the articulation of the links. By providing one section with links that permit articulation only in a vertical direction and another section with links that permit articulation only in a horizontal direction, flipping and twisting can be prevented.

Abstract: A gemstone presentation that includes two or more gemstones arranged in a row or multiple rows to form an array. A pair of prongs are positioned on opposite sides of each gemstone and a shared prong is positioned between each gemstone in the row or array so that each adjacent pair of gemstones is at least partially retained by the common or shared prong.

Abstract: A primary, finger-worn ring is provided with a secondary ring hingedly and selectively coupled about a stone on the primary, finger-worn ring. The secondary ring may be shaped and sized in accordance with the goal of fitting about a solitary or other stone embodiment placed on the primary ring.

Abstract: A temporary protective coating is provided over a low-E coated glass substrate. The temporary protective coating is preferably applied in solid form (i.e., as opposed to liquid form) so that no significant curing is needed. Moreover, the temporary protective coating can be easily removed by simply peeling it off just prior to heat treatment. In certain example embodiments, the temporary protective coating is designed such that it is not water soluble so that it remains on and protects the low-E coated glass substrate during washing step(s) and thereafter during at least some post-wash handling.

Abstract: An optical system that includes a molded optical element having a non-uniform refractive index distribution due to molding and a method of manufacturing the optical system is disclosed. Data of the non-uniformity of the refractive index distribution associated with molding of the molded optical element is acquired and used in order to determine the form of an aspheric surface of the molded optical element for correcting aberrations caused by the non-uniformity of the refractive index distribution. This data may be acquired by measuring the refractive index distribution of an optical element molded based on initial design values that are based on assuming uniformity in the refractive index distribution of the molded optical element or it may be computed based on the form of the molded optical element. The optical element may include a concave optical surface and may be a lens element that includes an aspheric surface.

Abstract: A method of manufacturing a precision glass sphere employed as a glass material (preform) in the molding of optical elements such as lenses, where the precision glass sphere that has been preformed with good weight precision and has an outer surface free of optically nonuniform layers. A method of manufacturing optical glass elements employing this precision glass sphere.

Abstract: A semi-convective forced air system for heating glass sheets during a heating cycle comprises a heating chamber having a length and a width, at least one heating element located within the heating chamber, a conveyor having a length and a width, the conveyor extending lengthwise through the heating chamber, a compressed air source, a plurality of air manifolds positioned within the heating chamber and in fluid connection with the compressed air source, each of the air manifolds having a length, and each of the air manifolds being oriented parallel to the length of the conveyor, and a plurality of nozzles mounted on each air manifold and in fluid connection with the air manifold for mixing together and directing toward the conveyor a combination of compressed air and over air to convectively heat a sheet of glass on the conveyor, the plurality of nozzles on each air manifold being spaced along the length of the air manifold.

Abstract: An apparatus for fabricating a soot preform for an optical fiber. The soot preform is fabricated by depositing glass particles on a starting rod capable of being rotated and pulled up. The apparatus comprises elements as follows. A reaction chamber is used for depositing the glass particles on the starting rod. An upper room is located above the reaction chamber for receiving the soot preform formed in the upper portion of the reaction chamber. At least one core burner is installed in the reaction chamber. A gas-supplying inlet is located in the top part of the sidewall of the reaction chamber closest to burner(s), and a gas-exhausting outlet is located in the top part of another sidewall opposite to the gas-supplying inlet. In addition, at least one cladding burner is installed in the reaction chamber.

Abstract: A control panel assembly for a washing machine is provided. The control panel assembly is installed at a case of the washing machine so that a user can handle the washing machine. The control panel assembly includes a circuit board, a cover and a member. The circuit board includes a given area having one or more displays densely attached thereon. The cover is attached on a case of the washing machine so as to cover the circuit board, and includes one window for showing all of the displays. The member is configured to be detachable from the window to thereby divide the window into several areas. The control panel assembly may further include a member attached on the window to thereby divide the window into several areas or cover boundaries between the displays.

Abstract: A detergent-supply system and a washing machine using the same. The detergent-supply system includes a guide rib formed on the bottom surface of a housing for guiding wash water, supplied to the rear part of the housing, to the front part of the housing, thereby washing out detergent remaining in the front part of the housing. The detergent-supply system further includes slits formed in the guide rib for spraying wash water, thereby completely eliminating the detergent remaining on the bottom surface of the housing.

Abstract: System with a machine for dyeing textile materials, of a type comprising a tank (10) inside which the dyeing of the materials (M) held in a basket (7) takes place and which is associated with means for the preparation and supply of a corresponding dyeing bath. The machine comprises a baskets-holding structure (5) able to be positioned within the relevant tank (10) and respectively removed therefrom; the said baskets-holding structure (5) intended for supporting a materials-holding basket (7) removably disposed thereon.

Abstract: A washing machine is provided with an out-of-balance correction system which can sense an out-of-balance condition of an inner tub during a washing cycle. More specifically, the correction system supplies an amount of balancing fluid to one or more receiving pockets formed in the inner tub about front and rear injection zones of the inner tub. Stationary injectors are provided to selectively dispense the balancing fluid through molded passages extending between an outer tub and the receiving pockets.

Abstract: A washing machine includes an out-of-balance correction system having a plurality of injector valves each having an associated solenoid element. Each of the injector valves is adapted to selectively inject a balancing fluid into a pocket carried by an inner tub to offset the out-of-balance condition. The valves are rapidly and repeatedly cycled to achieve a timed dispensing of the balancing fluid. To reduce the effects of the repeated cycling on the solenoid, a cushion element is mounted to a rear portion of a plunger carried within a solenoid coil. Additionally, a texturing process is applied to a pole piece arranged within the solenoid coil to establish a controlled leakage of air from a central portion of the cushion element once the plunger contacts the pole piece. With this arrangement, the service life of the injector valve is increased and proper control and timing of the injector valve is assured.

Abstract: A washing machine includes an inner tub rotatably mounted within an outer tub having a rear wall portion and a main body portion. A balancing fluid reservoir is molded to an upper region of the main body portion of the outer tub. The reservoir includes an opening leading to a plurality of fluid delivery channels molded along the rear wall portion of the outer tub. Preferably two channels are molded into the outer tub for delivering the balancing fluid to the inner tub, and a third channel for returning the balancing fluid to the reservoir. A cover plate, having a pair of receiver openings for injector valves, is positioned to close off the first, second and third channels.

Abstract: A multipurpose seal with a lock, including a mobile closure apparatus of a casing containing a lock and an attachment element designed to be locked in the casing. The lock includes a barrel configured to move in the casing between a locked position and an unlocked position. A remote-interrogatable electronic component including a data-storage is maintained in a housing, which passes through part of the casing and part of the lock barrel when the lock barrel is in the locked position. Thus, any rotation of the barrel from the locked position causes the component to break.

Abstract: An improved interlock device arranged in a locker comprises a cylinder, a poking rod, a frame, a plurality of wedging blocks, a latch structure, and a safety device. Wherein, the cylinder is arranged at the upper portion of the front panel of the locker and is adapted for locking or unlocking the locker; the front of the poking rod is connected to the cylinder, and the frame, being arranged at the rear of the locker, is a hollow square bar, and the latch structure is fitted inside the frame and is capable of moving upwardly and downwardly with the poking rod by connecting an side of the latch structure to one end of the poking rod, and the latch structure further comprises: a latch piece and a poke-positioning mechanism.

Abstract: A keyless latch for an anti-burglary window is positioned between an anti-burglary net window body and an outer window body, including a swing plate for swinging in the inside of a room, a helical member engaging with the swing plate, which then engages with and moving a latch body to shift linearly. Then the latch body can accordingly extend in or out of a latch hole so as to lock or unlock the anti-burglary net window body without a key. Then the anti-burglary window can form a through space for persons inside the room to escape out thereof in case of emergency. The swing plate can be hidden and protected to prevent the glass of the inner or the outer window body from cut illegally. At the same time the swing plate is located inside and impossible to reach from the outside, even if the inner window body is opened, attaining the anti-burglary effect.

Abstract: The invention provides a locking pin for a steering column lock assembly. The locking pin includes a dual taper defined by the first and second truncated cone portions. The first truncated cone portion narrows at a first angle and the second truncated cone portion narrows at a second angle, wherein the first and second angles are different from one another. The second angle can be less than the first angle. The dual taper of the locking pin reduces the likelihood that extreme torsion will not induce camming forces urging the locking pin out of engagement with a locking plate connected to the steering shaft.

Abstract: An operating device for a motor vehicle lock having a door lock actuator includes a grip plate and a grip with one bearing arm that extends through the grip plate and is swivellably linked to a rear side of the grip plate by means of a bearing block by way of a plug-type shaft. A securing element for the plug-type shaft secures the latter against sliding-out. A protective covering, which at least partially covers the rear side of the grip plate, has at least one extension that serves as a securing element and is situated next to an end of the plug-type shaft.

Abstract: Pushbutton lock where size reduction can be achieved by reducing the external dimension, including a planetary gear mechanism 18 where a drive gear serves as a sun gear 31 that is concentrically arranged within a casing 2 with an outside-house knob (operating member) 5, and a planetary gear 32a is arranged so that the range of revolution thereof with respect to the sun gear 31 overlaps the range of movement of a slider 17. Thereby, the slider 17 is moved in the unlock direction in response to the turning operation of the knob 5.

Abstract: A self-latching device is disclosed which is arranged to latch, in a predetermined position, two members which are otherwise movable relative to each other such as a hinged gate. The device comprises a latch arm having a latch element and a manual actuator mounted on one of the members and which is movable between a latched and a retracted position, by upward manual displacement of the actuator, and a retaining element incorporating a permanent magnet mounted on the other member. The latch arm is spring biased into the retracted position but, when in the predetermined position, is caused to move by the magnetic field generated by the magnetic into the latched position wherein any substantial relative movement of the two members is prevented by the latch arm engaging the retaining element.

Abstract: A key blank and key for a core having a plurality of pin bores penetrating from the core surface to the keyway, and a plurality of activator pins and filler pins, such that the installer can locate one or more activator pins in any of the pin bores, and one or more filler pins in any of the remaining bores, to thereby define a code to be provided in the respective flank or flanks of an authorized key. The key or key blank has a bonnet for grasping with fingers and a blade extending from the bonnet and having top and bottom edges spaced along a blade height direction and left and right opposed flanks having planar surfaces spaced apart along a blade width direction. Each of the flanks has a recessed longitudinal channel, and each channel has at least one raised node in the plane of a respective planar surface.

Abstract: A lock assembly incorporating a number of features designed to defeat attempts to pick or destroy the lock. The lock cylinder assembly employs multiple arrays of pass key pins, making picking of the lock much more difficult. Second, the arrangement of the pass key pins in separate arrays requires that multiple cuts would have to be made into the lock housing mogul or cylinder blank in order to defeat the lock cylinder assembly. Third, the lock cylinder assembly of the present invention may incorporate multiple sets of hardened dowel pins to prevent drilling through the lock housing mogul in the area of the driver pins. Fourth, the lock cylinder assembly of the present invention may incorporate a hardened cylinder shield behind the front face of the cylinder blank to prevent drilling through the cylinder blank.

Abstract: A process for conversion of organic wastes into biofertilizers such as soil conditioning agents of fertilizer grade, culture grade and soil grade is provided. Also provided is a process for conversion of organic wastes into material for converting waste water into reusable water. The invention provides methods for conversion of organic solid wastes to biofertilizers and reusable water in the presence of a geophagus earthworm Pheretima elongata culure to produce a variety of valuable soil conditioning products and reusable water.

Abstract: A hydroforming system includes a dual conical tube formed from a blank. The dual conical tube has a first end, a second end and a central portion positioned between the first and the second ends. The central portion has a smaller cross sectional area than the first and the second ends. A shaping die is adapted to receive the dual conical tube, and the shaping die is subject to pressurize such that the tube substantially approximates the shape of the shaping die.

Abstract: A thread rolling attachment (50) is adapted to be mounted on a machine tool and to be selectively moved in an axially direction relative to a workpiece (W) having a cylindrical surface upon which a thread is to be rolled.

Abstract: The present invention relates to a making method for a seamless metallic tube with a tilting roll type piercing rolling mill (piercer). According to the making method for a seamless metallic tube of the present invention, the rotary forging effect and the circumferential shearing strain can be significantly suppressed without generating uncompleted engagement of a billet. Accordingly, a product having reduced inside defects and excellent inside quality can be produced in high productivity. Further, by strengthening a plug nose rolling portion, a sharpened plug nose is obtained and an engagement limit can be increased. Additionally, a product further excellent in the inside quality can be efficiently produced. Accordingly, the present invention can be applied to wide fields of the piercing rolling of the seamless metallic tube.

Abstract: On a machine for bending rod-shaped or tubular workpieces, which includes a bending head having a bending mandrel mounted on a rotational axis and rotatable by means of a rotary drive, and having a clamping device for pressing the workpiece to be bent against a forming groove on the bending mandrel and also a feeding device for the workpiece to be processed, whereby the clamping device is positionable relative to the bending mandrel and can is also pivotable concentrically to the rotational axis of the bending mandrel, the clamping device is attached to two mutually independent rotary drives, one of which performs its pivoting movement about the rotational axis of the bending mandrel, and via the other of which it can be moved with respect to the bending mandrel by using an interposed conversion transmission that converts a rotary motion to a linear motion, whereby the bending head includes three concentrically nested rotary shafts for transmitting the drive of the three rotary drives to the bending mandrel,

Abstract: The invention relates to a device that is used to drive and support a tube (10) that is to be bent in relation to a bending head (3) which is disposed at the end of the frame (2) of a bending machine (1). Said device comprises: a guide shaft (11) which is solidly connected to tightening means (12), said tightening means being applied against the inner wall of the tube (10) to be bent; and movement means (6) which are common to the shaft (11) and the tightening means (12).

Abstract: A roller support block 10 supports rolling rollers (6˜9) in four stages and moves in a guide hole (13) of a pipe holder (5) to sequentially bring the rolling roller into pressure contact with a pipe (2) held immovable by the pipe holder (5) through an aperture (35) made in the pipe holder (5). In this process, the first-stage rolling roller (6) first comes into rolling pressure contact with the pipe for preliminary shaping of a recess. Subsequently, the second-stage and third-stage rolling rollers (7, 8) advance the preliminary shaping to enlarge and deepen the recess. Finally, the fourth-stage rolling roller 9 finally shapes the recess to a first locking groove (3 or 4).

Abstract: Rectilinear drawing machine for drawing material, especially bars, pipes or sections, with at least two movable drawing cars which are driven on a path, one run being assigned to each drawing car, and the runs can be fixed in a variable manner.

Abstract: A punch tool for punching orifice that has wall surfaces extending at an angle relative to a generally planar surface of a workpiece. The punch tool of the preferred embodiments is provided with configurations that, at the very least, increase the life of the tool, reduce damages to the workpiece during punching in the formation of the angled orifices.

Abstract: A method for draw forming a desired contour to the outer diameter of a tubular work piece provides that the selected work piece have a wall thickness uniform throughout its length. The outer diameter of selected work piece is reduced along essentially only a part of the starting metal blank by drawing the metal blank only partly through a die or only partly through each one of a succession of dies. The resulting drawn reduced diameter will have essentially the same wall thickness as the starting blank. If a thinner wall thickness is desired on the reduced outside diameter, an internal mandrel can be inserted in the starting tube, which will work with the draw die to decrease the resulting wall thickness of the drawn tube to an amount less than the starting tube. The workpiece recovered after the drawing method is useful for producing an automotive fuel tank filler tube or an automotive instrument panel support beam.

Abstract: An electromagnetically driven punch press is described. The punch press has an engine plate and a die set and a ram between the engine plate and die set. The engine plate has an assembly fixed thereto having a solenoid with windings that create a magnetic field when a current is applied. The engine plate has a feedback means positioned on the engine plate to provide real-time data on the position and velocity of the ram with respect to said engine plate.

Abstract: A method for enhancing the accuracy of a sensor is provided. The method includes determining a measure of the output of the sensor, determining whether the measure falls outside of an acceptable range for the output of the sensor, and, when the measure falls outside the acceptable range, modifying the measure of the output such that the measure falls within the acceptable range for the sensor.

Abstract: The invention relates to a method for determining the threshold value of screens which enable an evaluation of a sound coupling during the ultrasound testing of a series of spot welding joints of a selected type. Initially, a geometrical minimal thickness dMin is established for the spot welding joints. At least one echo of the front surface (entrance echo) is received in addition to one echo of the first reflection on a rear wall of the spot welding joint (first rear wall echo) and at least one further (n-th) rear wall echo. The propagation time tMin of the ultra sound pulse is defined for the path to the front surface to the rear wall and back to the front surface at a minimal thickness dMin and a propagation time tT for the total thickness. A first screen (B1) is set for the signal of the rear wall echo, starting at a moment in time t1S=tE+tMin?tSA and ending at a moment in time t1T=tE+tT+tSE, whereby tSA and tSE are additional small security measures.

Abstract: A method for carrying out operating tests of vibration level switches for liquids or solid bulk material or mixtures thereof is provided, whereby a vibration resonator (1) of a level detection sensor is excited by an oscillation exciting feedback circuit to oscillate, whereby at least one excitation parameter of a plurality of signal processing blocks (5, 6, 7, 8, 9, 10) of the feedback circuit is varied, and the resulting oscillation change is compared by a microprocessor (14) to datasets comprising data of corresponding oscillation changes of a failure free system. Moreover, a vibration level switch for measuring the level in containers for carrying out the inventive method is provided.

Abstract: The clipping diodes used to limit voltage during medical diagnostic ultrasound imaging operation are used during calibration operation for measuring amplitude and phase differences. The amplitude and phase measurements using clipping diodes as the calibration node may operate at any frequency, including frequencies less than 20 megahertz as well as frequencies above 20 megahertz. By using the diodes already present, a smaller or more compact calibration system may be provided. More simplistic integration may also result.