Abstract: An electromagnetic shielding structure has conductive parts for blocking propagation of electromagnetic interference, whereof at least one has an appendage or an edge configuration that is shaped so as to bite into the edge of the other of the conductive parts, such as along a narrowing groove. The appendage or edge can have a structure resembling an insulation displacement connector, but is arranged to engage the edge of a sheet-like or planar shielding element, as opposed to biting into an insulated wire. The connection achieves both electrical and mechanical connection between the parts, preferably thereby completing at least part of a shielding enclosure.

Abstract: A transmitter comprises an oscillator, a phase lock loop, a serializer, and an electrical-to-optical converter. The oscillator is enclosed in a metal shield. The metal shield is soldered to a ground ring of the printed circuit board. In one embodiment, the oscillator is voltage-controlled oscillator.

Abstract: The present invention provides a shield case comprising a frame body having an interior divided by partition plates and housing electronic components therein and a closure for providing electric shield by covering an opening portion of the frame body, and having a slit piece integrally formed with the closure by cutting out a part of the closure along a periphery except for a base portion to a raised form, the slit piece for coming into contact with an end of the partition plate, the slit piece being formed in a gutter shape from the base portion to the other end. Furthermore, the slit piece has the gutter shape which becomes greater in curvature radius from the base portion to the other end. This enables the shield case of the high-frequency device of the present invention to strengthen the contact between the slit piece formed with the closure for providing grounding and the partition plates provided within the frame body, whereby the reliable high-frequency device can be provided.

Abstract: A self-sealing apparatus for containing electrical energy associated with electrical components. The apparatus includes one or more removable devices maintained by a housing. Each of the removable devices contains electrical components therein and is separated from at least one other removable device by a clearance gap formed therebetween. A self-sealing barrier can be formed from the clearance gap, wherein the clearance gap surrounds the removable device in order to contain electrical energy associated with the electrical components when the electrical components are maintained within the removable device or extracted or inserted from or into the removable device.

Abstract: A shielding strip generally includes a longitudinally extending central region and at least one transversely extending slot along the longitudinally extending central region. The slot has at least one enlarged portion at about at about a predetermined area of high stress concentration.

Abstract: An isolation device includes an upper portion, a lower portion, and an isolation area. At least one of the upper and lower portions is constructed with a flexible shielding material. The isolation device may also include a conduit having one opening in the isolation area and another opening outside the isolation area.

Abstract: A radio frequency apparatus comprising a printed circuit board mounting an electronic component including a coil as an inductance element, a metal frame body covering this printed circuit board and connected to the ground, a lid formed integrally with the frame body, covering the inductance element mounting side of the frame body, and a leg formed by cutting and bending from the lid, having a width nearly same as the width of the coil, in which the leg is disposed closely to the coil.

Abstract: An enclosure for an electronic device has a front opening and rear opening formed by a base casing and a U-shaped cover mounted together thereon. A plurality of modular plates with electrical components pre-mounted thereon are removably and interchangeably mounted at selected positions in the front opening and rear opening of the base casing. The modular plates have an extension bottom leg portion having a shape and configuration with a complementary to those of mounting openings formed in even spacings along the entire length of the edge portion of the base casing. The modular plates also have an upper extension lip engageable with elongated channels formed on an underside edge portion of the front edge and rear edge of the cover.

Abstract: A compact computer system board 10 comprises dual on PCB expansion zones 11, 12, expansion connectors 113, 123 which can be connected to expansion boards. Once a expansion board is connected to the expansion connector 113 (123) in the on PCB expansion zone 11 (12) to extent the application of the system 10, a metal housing cover 20 will be mounted above the on PCB expansion zone 11(12). The shield expansion apparatus formed by on PCB expansion zone 11 (12) and metallic housing cover 20 isolates the electromagnetic interference between add-on expansion daughter card and the environment outside of the shield expansion apparatus. The metal housing cover 20 as well as the on PCB expansion zone 11 (12) function as the heat sink of the add-on expansion daughter card inside the apparatus.

Abstract: EMI shielding is provided for power electronics circuits and the like via a direct-mount reference plane support and shielding structure. The thermal support may receive one or more power electronic circuits. The support may aid in removing heat from the circuits through fluid circulating through the support. The support forms a shield from both external EMI/RFI and from interference generated by operation of the power electronic circuits. Features may be provided to permit and enhance connection of the circuitry to external circuitry, such as improved terminal configurations. Modular units may be assembled that may be coupled to electronic circuitry via plug-in arrangements or through interface with a backplane or similar mounting and interconnecting structures.

Abstract: A shielding module is used for shielding an electrical device. In this case, the shielding module includes a heat-dissipating component, a casing and a connection component. The heat-dissipating component has a contacting portion to contact with the electrical device. The electrical device is located in the casing, which has an opening. The heat-dissipating component is disposed in the opening. The connection component and the casing fasten the heat-dissipating component on the electrical device. Furthermore, an electrical apparatus is provided and includes an electrical device, a heat-dissipating component, a casing, and a connection component. In this case, the electrical device is fastened on a circuit board. The heat-dissipating component has a contacting portion adjacent to the electrical device. The electrical device is disposed in the casing, which has an opening. The heat-dissipating component is disposed in the opening.

Abstract: A shield and method for inhibiting electromagnetic interference (EMI) emissions from an enclosure is disclosed. The shield includes a cover portion and a plurality of extensions adjacent the cover portion, the extensions together at least partially defining a channel extending along at least a portion of the cover portion, the channel having substantially parallel boundaries, the channel being configured to received a portion of the enclosure and to slidably engage the enclosure such that, when engaged, the cover portion inhibits electromagnetic interference emissions from the enclosure. The method includes aligning a plurality of extensions of a shield with a portion of the enclosure and sliding the extensions into engagement with the portion of the enclosure until the shield covers an opening in the enclosure, thereby inhibiting electromagnetic interference emissions from the enclosure through the opening.

Abstract: Apparatus for housing electrically powered components to protect such components from damage and interference caused by lightning strikes and other externally generated magnetic fields. Methods of manufacturing such enclosures are also disclosed. A cable entry port and door entry are also disclosed.

Abstract: A contact assembly having a spring contact strip and a contact element, in particular, a subrack front panel. The spring contact strip has a contact limb that is bent over, with an end that can be freely pivoted. To improve the mechanical stability of the spring contact strip, the inventive contact limb extends an entire length of the spring contact strip.

Abstract: A storage apparatus includes a first rack having electrical conductivity, on which are mounted channel control parts receiving data input/output requests, and disk control parts performing read/write of data from and to disk drives, a second rack having electrical conductivity, on which are mounted disk drives, and relay parts for relaying communications between the disk drives and disk control parts; and communication cables for connecting disk control parts to relay parts. The communication cables include a transmission medium through which to transmit data, a first conductor having electrical conductivity and surrounding the transmission medium, a second conductor having electrical conductivity and surrounding the first conductor, and a covering surrounding the second conductor. The first conductor is connected to ground potential supply circuits provided in at least either disk control parts or relay parts, and the second conductor is connected to at least one of the first and second racks.

Abstract: A system is provided for channeling high frequency signals through sheet metal containment within an electronic device. In exemplary embodiments of the invention, an electronic device employing the system includes a midplane circuit board. One or more interface modules may be coupled to the midplane circuit board, for example, for providing a high frequency interconnect with other devices such as Fiber Channel or the like. A midplane chassis shield is disposed within the device's housing adjacent to the midplane circuit board so that the interface modules interconnect with the midplane circuit board through apertures formed in the shield wherein the midplane circuit board, midplane chassis shield and interface module cooperate for providing a low impedance tunnel for channeling high frequency signals to ground.

Abstract: An automatic switch includes a main body having connector ports provided thereon, more than one or two sets of cable-connected connectors directly extended from the main body, and a circuit board provided in the main body and electrically connected to the sets of cable-connected connectors via signal cables. The main body has an integral enclosure formed through multiple times of injection molding to include a circuit-protecting layer for enclosing the circuit board, an outer case enclosing the circuit-protecting layer, and an anti-slipping layer coating an outer surface of the outer case.

Abstract: A modular device with a housing includes at least one slot adapted for receiving an insert module and including a housing connector, each insert module includes a module connector for providing a connection with the housing connector, a driving device drives at least one of: the insertion and removal of the insert module into and out of the respective slot and includes two driving members and an actuator cooperating with one of the driving members for providing a displacement between the two driving members parallel to the plugging direction of the connectors, one of the driving members is mounted at the housing, while the other is mounted at the insert module, the actuator and one of the driving members are mounted at the housing or at the insert module, and the two driving members of the driving device are a projection extending perpendicularly to the plugging direction of the connectors.

Abstract: A housing adapted for receiving electronic cards therein, the housing comprising a chassis shielded from electromagnetic interference and having an opening in a face thereof. The chassis is adapted for receiving electronic cards therein. The chassis comprises a conductive cast shell Connector panels each have a printed circuit board body with a conductive plane, a card connector adapted for being connected to an electronic card in the housing, and input/output connectors. Each input/output connector is connected to the card connector by a printed circuit of the printed circuit board body. Each input/output connector is adapted for being connected to an input/output of a peripheral device. The connector panels are adapted for being mounted side by side and in shielding connection to cover the opening of the chassis so as to maintain an electromagnetic interference shielding of the housing.

Abstract: In the case of an electronic built-in device with a front wall and a built-in housing part comprising a cover, a base, side walls and a rear wall, and also with a printed circuit board, arranged transversely in relation to the rear wall, connected to at least two housing elements of the built-in housing part and carrying the electronic subassemblies and components of the built-in device and also a plug socket, the access to the contacts of the plug socket aligned parallel to the printed circuit board taking place through a clearance provided on the rear wall of the built-in housing part, it is provided that guiding surfaces are formed on the plug socket at right angles to the direction of the plug-in contacts of the plug socket, that the guiding surfaces of the plug socket are assigned within the built-in housing part a guide parallel to the rear wall, without any play, and that the diameters of the through-holes provided in the printed circuit board and serving for fastening the printed circuit board in the

Abstract: A shielding assembly and method for use with an electromagnetic field generating source. The assembly includes an outer housing that includes a conductive material. The outer housing defines a chamber in which the field generating source is located. A polymeric inner body substantially fills the chamber. The inner body is spaced from and circumscribes the field generating source. The field generating source may be the resonant oscillator of a microwave transceiver circuit and the inner body may advantageously include between 2–10%, by weight, of a semiconductive filler such as carbon or graphite. A printed circuit board may be attached to the outer housing to define the chamber together with the outer housing. The inner body may be secured within the chamber by compressive engagement between the printed circuit board and outer housing. Spacing elements are used to provide a clearance gap between the printed circuit board and the inner body.

Abstract: A shielding case for an electronic apparatus is provided. The shielding case houses a printed circuit board on which an electronic component and an output connector are mounted. The shielding case defines a recessed portion by its case wall. The recessed portion is provided with an opening located in a lateral direction from the mounting position of the output connector. The recessed portion is provided with an opening located in an upward direction from the mounting position of the output connector. The shielding case allows insertion of a cable either from above or sideways relative to the connector. Further, an aperture is provided in the case wall. The aperture is at a position that faces a side surface of the output connector when the connector is in the mounting position. It becomes possible to selectively employ one of a horizontal-insertion type output connector and a vertical-insertion type output connector.

Abstract: A system for dissipating static electric charge from electronics on a circuit board as the board is inserted into the enclosure, the system comprising one or more elastic, deformable and electrically conductive gaskets mounted within the enclosure for engaging ground pins on the circuit board.

Abstract: A shielding device includes an upper metal plate having downwardly extending and alternately disposed first and second plate sections and a lower metal plate having upwardly extending and alternately disposed third and fourth plate sections. Each of the first and fourth plate sections has an intermediate horizontal segment extending parallel to a respective metal plate. Each of the second and third plate sections has a recess structure such that after assembly the intermediate horizontal segments of the first and fourth plate sections are confined by opposite sidewalls of the recesses in the second and third plate sections, thereby preventing movement of the upper metal plate relative to the lower metal plate.

Abstract: An apparatus and method are provided for dissipating heat from an electronic component mounted in a conductive enclosure and for shielding electromagnetic radiation generated by the electronic component. A heat sink is configured to be mounted in thermal contact with the electronic component. An electrical conductor is operatively connected to the heat sink and configured to provide electrical contact between the heat sink and a surface of the conductive enclosure, thereby at least partially shielding the electromagnetic radiation generated by the electronic component.

Abstract: An audio rack has a first and a second storage location, the first storage location accepting a first electrical equipment that has a first width size, and the second storage location being disposed below the first storage location and accepting a second electrical equipment that has a second width size that is smaller than the first width size, the width of the second storage location being smaller than that of the first storage location.

Abstract: An electronic signal filter includes a cylindrical housing and a circuit board positioned therein having a plurality of peripheral edges and at least two circular through-holes formed therein. Each through-hole is inwardly spaced from one of the peripheral edges of the circuit board, defining a first distance between a respective one of the through-holes and a respective peripheral edge of the circuit board and defining a second distance between the through-holes. The filter also includes a ground strap attached to and spaced a distance above the circuit board. The ground strap includes a first portion, an integral second portion residing in and extending through each through-hole, and an integral third portion that contacts a portion of the second surface of the circuit board. At least a portion of the first portion of the ground strap contacts the inner peripheral surface of the cylindrical housing to ground the circuit board.

Abstract: An EMC shield is provided for electronic components on a printed circuit board, which has a housing which surrounds the electronic components at least on the sides not facing the printed circuit board and shields them against electromagnetic radiation, with the housing having a number of electrically conductive spring contacts which make electrically conductive contact with the printed circuit board, and the housing being pressed against the printed circuit board by means of at least one pressure contact-making device.

Abstract: An apparatus including a front panel (102) and a bezel (104) coupled to the front panel (102) and having a gasket (110), where the gasket (110) is affixed to the bezel (104) and electrically couples the bezel (104) to the front panel (102). Bezel (104) can be a mezzanine card bezel, a common mezzanine card bezel, and the like. A method of electrically coupling a front panel (102) to a bezel (104) includes providing a front panel (102) having an inner surface (112) defining a cut-out (114). Also, providing a bezel (104) having a perimeter (118), where the inner surface (112) of the cut-out (114) is designed to receive the bezel (104). Affixing a gasket (110) to the perimeter (118) of bezel (104) an the inner surface (112) receiving the bezel (104) where the gasket (110) is designed to be coupled to the inner surface (112), and electrically coupling the bezel (104) to the front panel (102) through the gasket (110).

Abstract: The position of a connector 36 in the forward direction (Ya direction) is determined by having front end surfaces 36f1, 36g1 of protrusions 36f, 36g of the connector that protrude from the left side surface and the right side surface of the connector, respectively, contacting vertical wall portions 72a1, 74a1 of positioning concave portions 72a, 74a of supporting plates 72, 74 of a housing of the shield case. The position of the connector in the backward direction (Yb direction) is determined by having a back surface 36h of the connector 36 contacting a protrusion 70a of a dividing plate 70. The motion of the connector in the right-and-left directions (Xa-Xb directions) is controlled by having the left side surface and the right side surface of the connector facing the supporting plates, respectively, in close proximity.

Abstract: There is disclosed an apparatus and method for protecting electronic devices against excessive heat build-up and particulate infiltration while implementing EMC shielding.

Abstract: A transceiver module assembly includes a printed circuit board (4), a plurality of transceiver modules, a plurality of electrical connectors (6) adapted to connect between the plurality of transceiver modules and the printed circuit board, and a shielding cage assembly (10) which is mounted to the printed circuit board for receiving the transceiver modules and the electrical connectors therein. The shielding cage assembly includes at least one shielding cage (21, 22), a spacer (3), and a hanger (1). The at least one shielding cage and the spacer are mechanically retained in the hanger, and the spacer mechanically engages with the shielding cage for good air ventilation.

Abstract: An electronic apparatus having a structure for protecting a flexible printed circuit (FPC) and a chip thereon is described, including a metal backplate, a first circuit and a second circuit respectively on the front side and the back side of the backplate, a metal frame plate at the periphery of the backplate, at least one FPC with at least one chip thereon, a metal screen plate, and at least one insulating elastic ring disposed around the FPC. The FPC has a first end connected to the first circuit and a second end connected to the second circuit over the frame plate, and the screen plate is disposed on the frame plate screening the FPC and the chip. The inner periphery of the insulating elastic ring closely contacts with the chip, and the outer periphery of the ring closely contacts with the frame plate and the screen plate.

Abstract: An assembly for mitigating at least one of an electrostatic discharge and electromagnetic interference is provided. The assembly includes (a) first and second spaced apart electrical conductors 108 and 116 and (b) a mitigation module 300 electrically coupled to the first and second spaced apart electrical conductors to control a magnitude of an electrostatic discharge and/or electromagnetic interference in the first and second electrical conductors 108 and 116. One or more of the following statements is true: (i) the mitigation module 300 comprises a ferrite material 304; (ii) the mitigation module 300 comprises a lossy dielectric material 308; and (iii) an equivalent electrical circuit for at least part of the mitigation module 300 comprises at least a first circuit segment 512 comprising a first inductor and a first capacitor electrically connected in parallel and a second capacitor 504 electrically connected in series with the first circuit segment 512.

Abstract: An EMI shielding gasket for reducing the amount of force required during the mounting process. The present invention provides an extended lip feature on the gasket to facilitate the installation process and to function as a lead-in, such that less force is required by the assembler when mounting the EMI gasket. As less manipulation may be required to install the gaskets, gaskets may be mounted correctly more often, thereby preventing the occurrence of EMI leakage. The present invention also reduces the possibility that the EMI gaskets may become damaged due to excess manipulation, and assemblers may experience fewer physical problems related to manipulating the gaskets. By reducing the amount of force required to mount the EMI gaskets, the present invention may increase productivity by decreasing assembly time, decrease rework of improperly assembled or damaged gaskets, and reduce health risks and subsequent insurance claims of assemblers during manufacturing.

Abstract: A ball grid array package includes a chip having a substrate with a bottom surface, a plurality of solder bumps projecting outwardly from the bottom surface of the substrate, and an electromagnetic shield including a housing that defines an inner space which receives the chip and the solder bumps therein, and a bottom opening for access into the inner space. The solder bumps project outwardly of the inner space through the bottom opening in the housing.

Abstract: An electromagnetic interference (EMI) shielding cage for an electronic module is comprised an electrically-conductive bottom, an electrically-conductive rear panel electrically coupled to said bottom, an electrically-conductive, elongated cover electrically coupled to said bottom and first and second side walls that are electrically and mechanically coupled to said bottom, said rear panel and said elongated cover. Numerous ground lugs, electrically coupled to at least one of: said bottom; rear panel; and first and second side walls provide an electrical pathway for EMI signals to a reference potential. An electrically-conductive, compressible gasket encircling the bottom, top and side walls provides an electrical connection to a front panel, providing additional EMI suppression. Gasket engagement tabs in the top and bottom provide electrical connection between the gasket and panels.

Abstract: An integrated drive panel for a peripheral/drive bay within the case of a computer or like electronic device comprises a cover assembly having an integral EMI shield. The integrated drive panel does not require removal of the front bezel of the computer case or access to the peripheral/drive bay from inside the computer case during installation and removal.

Abstract: A power feedforward amplifier uses integral cavities to provide RF isolation between subcircuits of the power amplifier. The chassis includes a main chassis body and a lid structure adapted to couple with the chassis body and define the subcircuit cavities. The inner lid includes an amplifier dividing wall and interstage walls adapted to isolate the main and error amplifier subcircuits of the feedforward power amplifier and further to isolate individual components of the subcircuits. In one embodiment, the amplifier subcircuits are mounted on a single circuit board and isolated from each other by the dividing wall. A delay line subcircuit portion is integral with the main chassis body and is coupled beneath the error amplifier subcircuit to contain and electromagnetically shield a delay line filter subcircuit while providing direct connection with the error amplifier.

Abstract: According to one embodiment, a computer system is disclosed. The computer system includes a circuit board, and connectors mounted on the circuit board. Each connector supports a peripheral component interface (PCI) card. In addition, the computer system includes a shroud that encloses the connectors in order to separate the associated PCBs from other components on the circuit board.

Abstract: An electromagnetic shielding plate having high shielding effect is provided. The electromagnetic shielding plate is formed of a conductive plate having elasticity and is provided on the edge thereof with a connecting strip bent in such a manner that the tip thereof projects from the surface of the plate, and with a supporting portion. When the electromagnetic shielding plate and the printed substrate are connected, it is ensured that the ground pattern 201 of the printed board 200 and the connecting strip are brought into contact with respect to each other, thereby a high shielding effect can be obtained.

Abstract: A docking apparatus for printed circuit boards including a cassette housing, having a housing base, a housing cover and a housing wall, wherein the housing base and the housing wall are disposed relative to each other so as to define a housing cavity for containing a printed circuit card and wherein the housing wall includes a cable opening disposed so as to be communicated with the housing cavity, a housing bezel, disposed relative to the cassette housing so as to be associated with the cable opening and translatable therein, the housing bezel is in electrical communication with the printed circuit card and translatable therewith when the printed circuit card is engaged and disengaged with a printed circuit board, and an EMC sealing device disposed between the housing bezel and the cassette housing, the EMC sealing device configured to provide a movable EMC seal proximate the cable opening while still allowing airflow therethrough while covering a portion of the cable opening created between the housing and

Abstract: There is provided a portable communication device for minimizing the SAR of electromagnetic waves. In the portable communication device, a slim upper housing has an FBC on which a keypad is mounted, a lower housing is vertically spaced from the slim upper housing by a predetermined distance and includes a PCB assembly, and a middle housing is positioned between the slim upper housing and the lower housing, spatially isolated from the lower housing by a separation plate to minimize the adverse effects of electromagnetic waves generated from the PCB assembly, and has a slot opened from the front end to hold an object in the lengthwise direction. A sliding battery pack is insertable to and detachable from the middle housing in the lengthwise direction.

Abstract: A supplemental shield is used to cover a radiation leakage path through a chassis of the system. The supplemental shield is attached to at least one surface in the system to cover the radiation leakage path. In one arrangement, the supplemental shield has an adhesive portion to attach the supplemental shield to the at least one surface.

Abstract: The present invention provides in-line equipment and methods for manufacturing an EMI/RFI shield that is integrated formed in a formable sheet. The EMI/RFI shield may comprise a shaped thermoform shell that has one or more conductive layers applied to one or more surfaces. The EMI/RFI shield may be integrally formed with the formable sheet via attachment tabs that are positioned along one or more edges of the EMI/RFI shield.

Abstract: A secure electronic circuit on a printed circuit board is disclosed. The electronic circuit is enclosed in a housing comprising two shells located in abutment with opposite faces of the printed circuit board. One shell is provided with a first element that extends through an aperture in the printed circuit board and the other shell is provided with a second element that irreversibly engages with the first element and thereby secures both shells to the circuit board and inhibits removal of either shell. The construction is such that removal of either shell results in irreversible damage to the housing.

Abstract: An expansion enclosure allows additional expansion cards to be used with a computer system. The enclosure exhibits a small footprint (e.g., one rack unit, or 1¾ inches) for installation in a rack or other area in which space is limited. The enclosure accepts one or more (e.g., four) expansion cards, which are connected to a removable expansion card cage. The removable cage forms part of the structure of the enclosure and provides strength and rigidity. A stabilizer may be removably but securely installed in the enclosure to stabilize or hold the removable cage as a card is installed in or removed from the cage.

Abstract: A keyed filler panel with removably-coupleable airflow resistive filler card assembly is disclosed. In one embodiment, the present invention is comprised of a filler panel body. The present embodiment is further comprised of an airflow resistive filler portion removably-coupleable with said filler panel body. The airflow resistive filler portion adapted to couple with the filler panel body without additional hardware.

Abstract: An adapter using an electrically-conductive wall within the adapter to channel EMI emissions to ground. In a preferred embodiment, the adapter comprises: (a) an elongated housing having a first and second end and defining a first passageway extending axially from the first end toward the second end, and a second passageway extending axially from the second end toward the first end, each passageway configured to receive an optical connector plug; (b) an electrically-conductive wall traversing the adapter between the first and second passageways, the wall being sized to cover a substantial portion of the opening when the adapter is mounted to the chassis; and (c) at least one portion of the wall extending outside of the housing to electrically couple with the chassis of the computer system when the adapter is mounted to the chassis forming an electrically-conductive path between a point on the wall and the chassis.

Abstract: A seismic data acquisition module includes a motherboard that is environmentally protected as a independent unit by an integral sheath, envelope or encapsulating cover. The motherboard unit is suitably configured for rapid and frequent manual removal from the interior cavity of a protective outer housing for compact and more secure packaging as well as more convenient transport over great distances, if necessary, to successively different survey sites. At a new survey site, the motherboard units may be inserted into more bulky but also more rugged or waterproof outer housings that are provided with environmentally tight cable connectors. The outer housings, having a capital value of only a fraction of the electronic motherboard units, may have arrived at the new site at a different time and may even be distributed in the new survey field at the time the motherboard units arrive.