Abstract:
A circuit element is provided for mounting in an electrical connector. The circuit element includes a one-piece toroidal core made of a sintered, ferrite material. The core has a central bore therein defining an inner surface, an outer surface and oppositely facing top and bottom surfaces, and a plurality of equally spaced apart longitudinal channels formed in one of the top, bottom, inner and outer surfaces. A plurality of wires are twisted together in a uniform, repeating pattern to define a group of twisted wires. The group of twisted wires extends through the central bore and is wrapped around the core to define a plurality of uniformly spaced longitudinal turns with a portion of each turn being positioned in one of the channels.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Application No. 61/170,221, filed Apr. 17, 2009, which is incorporated herein by referenced in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates generally to modular telecommunications jacks and, more particularly, to a high speed modular jack having improved circuitry therein. 
         [0003]    Modular jack (“modjack”) receptacle connectors mounted to printed circuit boards (“PCBs”) are well known in the telecommunications industry. These connectors are typically used for electrical connection between two electrical communication devices. With ever-increasing operating frequencies of data and communication systems and an increased density of information to be transmitted, the electrical characteristics of such connectors are of increasing importance. In particular, it is especially desirable that these modjack connectors do not negatively affect the signals transmitted and that no additional interference is introduced into the system. Based on these requirements, various proposals have been made in order to potentially minimize negative influences of modjack connectors used with communication or transmission links. 
         [0004]    When used as Ethernet connectors, modjacks generally receive an input signal from one electrical device and then communicate a corresponding output signal to a second device coupled thereto. Magnetic circuitry can be used to perform filtering of the signals during transfer of the signals from the first device to the second and typically use either a transformer and a single or a dual channel ferrite choke. Such chokes typically are toroidal magnetic ferrite common mode chokes and are used to reduce the amount of unwanted common mode noise in differential signaling applications. Modjacks having such magnetic circuitry are typically referred to in the trade as magnetic jacks. 
         [0005]    For the elimination of in-phase interference signal noise components, U.S. Pat. No. 5,015,204 describes the use of a common-mode choke arranged in a connector housing around which the contact leads of a RJ-45 modjack connector are integrally wound. In this design, the common-mode choke takes up a substantial portion of the connector housing even though only two signal-conducting leads are used. Furthermore, the respective leads need a certain rigidity to provide resilient forces to continuously facilitate a secure contact with the associated modular plug connector. Unfortunately, this makes for difficult manufacturing conditions, especially when the rigid wires have to be wound around the conductive core of the choke coil and the entire assembly placed within the modjack housing. 
         [0006]    Typical magnetic jacks utilized a dielectric housing with conductive metal terminals therein for connecting to conductive metal terminals of a mating plug connector. The housing and terminals of the magnetic jacks are configured so that magnetic subassemblies may be inserted therein that are operatively connected to the terminals of the magnetic jack. These magnetics typically utilize a toroid-shaped magnetic core having a plurality of wires wound around the core in order to create a transformer and/or a choke. 
         [0007]    As system speeds have increased, increasing the speed of signals that pass through the magnetic jacks has become a significant challenge due to difficulties in maintaining the consistency of the magnetics. The significance of the inconsistencies depends on the speeds at which the magnetic jacks are expected to perform. Magnetic cores that operate within a predetermined range of electrical tolerances at one signalling frequency may have enough electrical inconsistencies so as to be out of tolerance or inoperable at higher signaling frequencies. 
         [0008]    Furthermore, even if the wound magnetic subassemblies are precisely manufactured, such subassemblies must also be mounted to housing during the manufacturing process. Given the small size of the magnetics and the connector housings, there is a potential for the magnetics to be damaged or to be become out of specification during installation. In some instances and depending on the speed of the signals passing through the magnetic jack, it may be possible to manually rework the magnetics so that the magnetic jack will operate effectively. In other instances, the magnetic jack may be beyond repair and must be discarded as scrap. Accordingly, in one instance additional labor is required to create an operative jack. In the other, the magnetic jack would be deemed defective. Both of these scenarios substantially increase the cost of manufacturing the magnetic jacks. According, improvements to the design of a magnetic jack would be appreciated by certain individuals. 
       SUMMARY OF THE INVENTION 
       [0009]    Accordingly, a toroidal circuit element is provided that includes a one-piece toroidal core made of a magnetically permeable material. The core has a central bore therein defining an inner surface, an outer surface and oppositely facing top and bottom surfaces. A plurality of equally spaced apart longitudinal channels are formed in one of the top, bottom and outer surfaces. The toroid can used to provide a circuit element in an electrical connector. The circuit element could include the one-piece toroidal core made of a sintered, ferrite material. The core has a central bore therein defining an inner surface, an outer surface and oppositely facing top and bottom surfaces, and a plurality of equally spaced apart longitudinal channels formed in one of the top, bottom and outer surfaces. A plurality of wires are twisted together in a uniform, repeating pattern to define a group of twisted wires. The group of twisted wires extends through the central bore and is wrapped around the core to define a plurality of uniformly spaced longitudinal turns with a portion of each turn being positioned in one of the channels. In an embodiment, a modular jack may be provided that includes an insulative housing for receiving a mating plug. The housing can include a cavity therein that can receive the circuit element so as to allow for receiving a circuit element to condition signals passing through the jack and a plurality of terminals operatively connected to the magnetics and configured to engage contacts of a corresponding mating plug. Thus, certain aspects of the above-described problems encountered by conventional magnetic jacks can be addressed by providing a structure for maintaining consistent performance of the circuit elements within the magnetic jacks. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    Various other objects, features and attendant advantages of the disclosure will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views in which: 
           [0011]      FIG. 1  is a front perspective view of an embodiment of a magnetic jack; 
           [0012]      FIG. 2  is a partially exploded view of the magnetic jack of  FIG. 1  with the outer shielding removed; 
           [0013]      FIG. 3  is a partially exploded rear perspective view of the magnetic jack housing of  FIG. 2  with the internal modules in various stages of insertion therein; 
           [0014]      FIG. 4  is a rear perspective view of a single internal module; 
           [0015]      FIG. 5  is an exploded view of the internal module of  FIG. 4 ; 
           [0016]      FIG. 6  is perspective view of one of the component housings of  FIG. 5  prior to insertion of the noise reduction components therein and with the windings removed for clarity; 
           [0017]      FIG. 7  is a perspective view identical to that of  FIG. 6  with the noise reduction components inserted therein and with the windings removed for clarity; 
           [0018]      FIG. 8  is a perspective view of an embodiment of a transformer toroid; 
           [0019]      FIG. 9  is a top plan view of the transformer toroid of  FIG. 8 ; 
           [0020]      FIG. 10  is a side elevational view if the transformer toroid of  FIG. 8 ; 
           [0021]      FIG. 11  is a perspective view of an embodiment of a transformer toroid; 
           [0022]      FIG. 12  is a top plan view of the transformer toroid of  FIG. 11 ; 
           [0023]      FIG. 13  is a sectioned perspective view of the transformer toroid of  FIG. 11 ; 
           [0024]      FIG. 14  is a cross-sectional view of the transformer toroid taken generally along line  14 - 14  of  FIG. 12 ; 
           [0025]      FIG. 15  is a side elevational view of the twisted wires used with the noise reduction components of the disclosed embodiments; 
           [0026]      FIG. 16  is a perspective view of a transformer toroid of  FIG. 8  with only the central winding section wound thereon; 
           [0027]      FIG. 17  is a side elevational view of a two transformer and choke subassembly; 
           [0028]      FIG. 18  is a side elevational view of the two transformer and choke subassembly of  FIG. 17  inserted into a receptacle in the component housing; 
           [0029]      FIG. 19  is a front perspective view of an embodiment of a single port magnetic jack; 
           [0030]      FIG. 20  is a partially exploded view of the magnetic jack of  FIG. 19  with the outer shielding removed; 
           [0031]      FIG. 21  is a partially exploded front perspective view of the magnetic jack housing of  FIG. 19  with the internal module removed therefrom; 
           [0032]      FIG. 22  is a front perspective view of the internal module; 
           [0033]      FIG. 23  is an exploded view of the internal module of  FIG. 22 ; and 
           [0034]      FIG. 24  is perspective view of the component housing of  FIG. 23  prior to insertion of the noise reduction components therein and with the windings removed for clarity. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0035]    The following description is intended to convey the operation of the depicted exemplary embodiments to those skilled in the art. It will be appreciated that this description is intended to aid the reader, not to limit the invention. As such, references to particular features are merely intended to describe the feature, not to imply that every embodiment must have each of the described characteristic. Therefore, unless otherwise noted, features disclosed herein may be combined together to form additional combinations that were not otherwise shown for purposes of brevity. 
         [0036]    As noted above, it is generally desirable to minimize electrical inconsistencies in the magnetic properties of a magnetic jack. It has been determined that inconsistent spacing in the windings results in electrical inconsistencies within a particular wound core such as differences in capacitance between adjacent windings together with differences in inductance from one winding to the next. In addition, inconsistencies from one wound core to the next will also typically exist and contribute to inconsistent performance between wound cores. In particular, when winding the wires around the toroid-shaped core, it is desirable to maintain equal spacing between the windings. However, since the toroid-shaped cores are very small, as are the wires wound therearound, the winding operation is typically performed by hand and thus the spacing is typically inconsistent to some degree. It has been determined that relatively minor inconsistency can have a significant impact on the performance of the magnetics as a 0.5 pF variation in the performance of the transformer core can cause the magnetics to be out of tolerance. 
         [0037]    In addition, since it is desirable to minimize the size of the magnetic jacks, the housing is generally small and thus the space into which the wound magnetic subassemblies are positioned in is also small. In an embodiment where the magnetic subassembly is placed into a cavity in the housing, insertion of the wound magnetic subassembly into its respective receptacle may cause the wound wires on the outer surfaces of the toroid-shaped cores to contact or snag on the edges of the receptacle into which the subassembly is being inserted; thus changing the spacing between the windings and potentially even damaging the windings. Thus, installation of the magnetics has the potential to negatively impact the electrical performance of the wound magnetic subassembly. As will be discussed below, one method to help compensate for movement of the windings is to provide channels in the core to help retain the winding in its desired position. The channels may even have sufficient depth to allow the windings to be completely protected by the channel. 
         [0038]      FIGS. 1-2  illustrate the front side of an exemplary embodiment of modular jack. As shown, magnetic jack  100  is a multiple input, stacked jack for receiving multiple Ethernet or RJ-45 type of plugs (not shown). The magnetic jack  100  includes a housing  102  made of an insulating material such as a synthetic resin (for example, PBT) and includes front side openings or ports  103  that are configured to receive Ethernet or RJ-45 type jacks (not shown). The magnetic jack  100  is configured to be mounted on circuit board  104 . A metal or other conductive shield assembly  106  surrounds the magnetic jack housing  102  for RF and EMI shielding purposes as well as for providing a ground reference. It should be noted that, as shown in  FIGS. 23-28 , a similar configuration is possible where only a single unit magnetic jack is desired. 
         [0039]    In this description, representations of directions such as up, down, left, right, front, rear, and the like, used for explaining the structure and movement of each part of the disclosed embodiment are not absolute, but relative. These representations are appropriate when each part of the disclosed embodiment is in the position shown in the figures. If the position of the disclosed embodiment changes, however, these representations are to be changed according to the change of the position of the disclosed embodiment. 
         [0040]    Shield assembly  106  includes a front shield component  106   a  and a rear shield component  106   b . These joinable shield components are formed with interlocking tabs  108  and openings  110  for engaging and securing the components together when the shield assembly  106  is placed into position around the magnetic jack housing  102 . Each of the shield components  106   a ,  106   b  includes ground pegs  112 ,  114  that extend into through-holes  116  on the circuit board  104  when placed thereon. As shown in  FIG. 3 , the rear portion of the magnetic jack housing  102  includes relatively large openings  115  that are sized and shaped to receive internal subassembly modules  118  ( FIG. 4 ). These modules  118  provide the physical contacts for engaging Ethernet plugs and also provide the electrical filtering functionality of the jacks. 
         [0041]    Referring to  FIGS. 4 and 5 , subassembly module  118  includes a contact module  120  that is electrically connected to a top PCB  122 . The top PCB  122  is mounted to a component housing  126 , which includes magnetic circuits and filtering components. Bottom PCB  124  is mounted on the bottom of component housing  126 . The top and bottom PCBs  122 ,  124  include the resistors, capacitors and any other components associated with the chokes and transformers located inside the component housing  126 , which together comprise the filtering circuitry of the magnetic jack. 
         [0042]    Contact module  120  includes a top contact assembly  121   a  and a bottom contact assembly  121   b  for providing a stacked jack, or dual jack, functionality. The top contact assembly  121   a  provides physical and electrical interfaces, including upwardly extending contact terminals  128 , for connecting to an Ethernet plug. The bottom contact assembly  121   b  is physically connected to the top contact assembly  121   a  and includes downwardly extending electrically conductive contact terminals  130 . The contact module  120  is electrically connected to the top PCB  122  through leads  132 , which are soldered, or electrically connected by some other means such as welding or conductive adhesive, to a row of PCB pads  134  that are positioned along the top of PCB  122  along one edge thereof and a second, similar row of PCB pads (not shown) on a lower surface of top PCB  122 . 
         [0043]    Referring to  FIG. 5 , component housing  126  is a two piece assembly having a right housing  136   a  and left housing  136   b  for holding the magnetics  151 . A shock absorbing foam insert  150  for holding and cushioning the magnetics is provided as well. The left and right housings halves  136   a ,  136   b  are formed from a synthetic resin such as LCP or other similar material and preferably are physically identical for reducing manufacturing costs and increased ease of assembly. A latch projection  138   a  extends from the right sidewall  142  of each housing. A latch recess  138   b  is located in the left sidewall  140  of each housing and lockingly receives latch projection  138   a  therein. Each housing half  136   a ,  136   b , is formed with a large box-like receptacle or opening  144  ( FIG. 6 ). This receptacle  144  receives the filtering magnetics  151  therein. 
         [0044]    The magnetics  151  provide impedance matching, signal shaping and conditioning, high voltage isolation and common-mode noise reduction. This is particularly beneficial in Ethernet systems that utilize cables having unshielded twisted pair (“UTP”) transmission lines, which are more prone to noise pickup then shielded transmission lines. The magnetics help to filter out the noise and provide good signal integrity and electrical isolation. The magnetics  151  include four transformer and choke subassemblies  152  associated with each port  103 . The choke is configured to present high impedance to common-mode noise but low impedance for differential-mode signals. A choke is provided for each transmit and receive channel and each choke is wired directly to the RJ-45 connector. 
         [0045]    Referring now to  FIGS. 5-7 , after the transformer and choke subassemblies  152  are assembled as described below, the component housings  126  are assembled. Each housing  136   a ,  136   b  receives four magnetic subassemblies  152 , and wire leads are connected to electrically conductive metal pins  154  such as by soldering as is known in the art. The foam shock absorbing insert  150  is placed inside one of the housing halves  136   a ,  136   b  and such insert  150  is sized such that a significant portion thereof extends out from the opening  144  of its respective housing half before the two housing halves are connected together. 
         [0046]    During assembly of the housings halves  136   a ,  136   b , the shock absorbing foam insert  150  compresses against the magnetics  151  so that the insert  150  is deformed to the point of filling in spaces and crevices between the various transformers and chokes. The foam insert  150  also presses the transformers and chokes against the sidewalls of the opening  144  of their respective housings to hold the magnetics in place and reduce the likelihood that a sudden or hard movement could possibly break the components or cause the windings to break. 
         [0047]    As described above, the magnetics  151  include two transformer and choke subassemblies  152  associated with each port  103  of the connector. Referring to  FIG. 8 , one embodiment of a magnetic subassembly  152  can be seen to include two magnetic ferrite transformer cores  160 , a dual magnetic ferrite choke core  180 , transformer windings  182  and choke windings  190 . 
         [0048]    A first embodiment of the transformer core  160  is depicted as a toroid or donut shape in  FIGS. 8-10 . Transformer toroid  160  includes substantially flat top and bottom surfaces  161  and  162 , a central bore or opening  163  that defines a smooth, cylindrical inner surface  164  and an outer surface  165 . Outer surface  165  is also generally cylindrical and includes a series of elongated channels or notches  166  formed therein that extend from the top surface  161  to bottom surface  162 . The toroid is symmetrical about a central axis  167  except for the channels  166 . A vertical cross section of the toroid  160  is generally rectangular. Channels  166  are evenly spaced apart on outer surface  165  around the central axis  167 . In the embodiment shown, nine evenly spaced channels  166  are depicted so that the channels are forty degrees apart around the central axis  167 . The actual number of channels is determined based upon the desired number of times twisted wires  183  are turned around toroid  160  as described below. The depth of the channels  165  is determined so that a portion of each twisted wire extends into its respective channel a sufficient depth to retain the twisted wire therein. In an embodiment, the channels  165  may have a depth sufficient to minimize any rubbing of the twisted wires when the transformer core is inserted into the respective housing. In other words, the channel may be of sufficient depth to not only restrain the winding in the desired location but also to ensure the wires do not extend beyond the outer surface (and/or top surface and/or bottom surface if the channel is so configured) so that when the transformer core is inserted the wires are protected from damage. In an embodiment, the depth of the channels may be greater than a diameter of the twisted wires. The toroid may be formed from a magnetically permeable material such as a soft ferrite or iron or by any other material with desirable magnetic properties. 
         [0049]    A second embodiment of the transformer toroid core  170  depicted in  FIGS. 11-14  is substantially similar to transformer toroid  160  except that the channels  176  extend into and around the top surface  171  and the bottom surface  172  of toroid  170  in an arcuate manner so that a upper portion  176   u  of channel  176  extending through the top surface  171  and a lower portion  176   l  of channel  176  extending through the bottom surface  172  are arcuate or generally “C-shaped” as best seen in  FIG. 13 . In other words, each channel  176  includes a generally straight outer section  176   o  along or through the outer surface  175  and a pair of arcuate upper and lower portions  176   u  and  176   l  that extend along or through the top surface  171  and the bottom surface  172 , respectively, of transformer toroid core  170 . The upper and lower portions  176   u  and  176   l  of channels  176  extend from the top and bottom of outer section  176   o  and end at the central bore or opening  174  which defines a smooth, cylindrical inner surface  175  of toroid  170 . 
         [0050]    As best seen in  FIG. 13 , a vertical cross section  178  of toroid  170  taken through channel  176  is generally oval-shaped while a vertical cross section  179  of toroid  170  taken between channels  176  is generally rectangular. The C-shaped upper and lower portions  176   u  and  176   l  are desirable so that the twisted wires  183  closely follow the channel  176  as they are wrapped around toroid  170 . Air gaps between the twisted wires  183  and toroid  170  can cause a loss of magnetic flux, which will tend to result in less efficient signal transfer and a resultant signal loss. Therefore, further beneficial consistency improvements are possible if the air gap can be reduced. 
         [0051]    The dual magnetic ferrite choke core  180  is formed by sintering a magnetically permeable material such as soft ferrite or iron and includes a pair of bore or holes  181   a ,  181   b  through which the choke windings  190  are wrapped. By providing the two bores  181   a ,  181   b , the core may support two transformer channels. If desired, the dual magnetic ferrite choke core  180  could be replaced with a pair of toroid shaped cores similar to transformer cores  160 ,  170 . While dual magnetic ferrite choke core  180  is illustrated as having smooth surfaces about which wire  183  are wrapped and engage, channels similar to channels  166 ,  176  of toroids  160 ,  170  could be provided in dual magnetic ferrite choke core  180  in order to accurately position (and protect if the channels are deep enough) wires  183 . 
         [0052]      FIG. 15  illustrates a group of four wires  183  that are initially twisted together and wrapped around the transformer toroid  160 . Each of the four wires is covered with a thin, color-coded insulator to aid the assembly process. As used herein, the four wires  183  are twisted together in a repeating pattern of a red wire  183   r , a natural or copper-colored wire  183   n , a green wire  183   g , and a blue wire  183   b . The number of twists per unit length (if twists are used), the diameter of the individual wires, the thickness of the insulation as well as the size and magnetic qualities of the toroids  160  and  170 , the number of times the wires are wrapped around the toroids and the dielectric constant of the material surrounding the magnetics are all design factors utilized in order to establish the desired electrical performance of the system magnetics. 
         [0053]    As shown in  FIG. 16 , the four twisted wires  183  are inserted into central bore or opening  163  of toroid  160  and are wrapped around the outer surface  164  of toroid  160  and within channel  166 . The twisted wires  183  are re-threaded through central bore  163  and this process is repeated until the twisted wire group  183  has been threaded through the central bore nine times and the twisted wires positioned in eight of the nine available channels  166 . As a result, the twisted wires  183  wrap around the outer surface  165  of toroid  160  eight times. Through such structure, it is possible to precisely and evenly space apart the twisted wires  182  that are located in channels  166  along the outer surface  165  of transformer toroid  160 . It should be noted that the twisted wires  183  are wrapped around toroid  160  eight times even though there are nine channels  166  depicted. Depending on the desired electrical performance, it may be useful to align a portion of the windings with the remaining open channel so that nine turns are effectively created around toroid  160 . 
         [0054]    Referring to  FIGS. 16-18  the twisted wires  183  exiting from opposite ends of the central bore are separated and certain of the twisted wires combined and re-twisted as is known in the art. For example, the natural colored wire  183   n  exiting from one end of central bore  163  is combined with the blue colored wire  183   b  exiting from the other end of central bore  163  and twisted together to form natural and blue choke twisted wires  183   nb . Such natural and blue choke twisted wires  183   nb  extend into one of the bores  181   a  of dual magnetic ferrite choke core  180 . The choke twisted wires  183   nb  are re-threaded through bore  181   a  and this process is repeated until the choke twisted wires  183   nb  have been threaded through bore  181  ten times and the choke twisted wires  183   nb  evenly spaced around bore  181   a . Since the choke core  180  is of the type having two bores  181   a ,  181   b , the choke twisted wires  183   nb  may not be positioned completely around the entire circumference of bore  181   a . Regardless, it is desirable to maintain even spacing of the choke twisted wires. For example, if the result of inserting the choke twisted wires  183   nb  ten times into bore  181   a  is nine turns and the wires are spread out evenly over one hundred eighty degrees, the choke twisted wires  183   nb  will be approximately twenty two and one half degrees apart. If desired, channels similar to the channels  166  and  176  of transformer cores  160  and  170  could be formed in choke core  180  in order to accurately and securely position choke twisted wires  183   nb  in their desired locations. 
         [0055]    Referring to  FIG. 17 , a completed two transformer and choke subassembly  152  is shown. The twisted wires  183  (other than the natural wire  183   n  and the blue wire  183   b  that form the choke twisted wires  183   nb ) are generally grouped together such that the red wires  183   r  and green wires  183   g  extend downward while the natural wires  183   n  and the blue wires  183   b  extend upward. The two transformer and choke subassembly  152  is then inserted into receptacle  144  of housing half  136   a ,  136   b  and the wires are connected to electrically conductive metal pins  154  such as by soldering as described above. As best seen in  FIG. 18 , receptacle  144  is only slightly larger than two transformer and choke subassembly  152 . Thus, without channels  166 ,  176 , the transformer windings  182  are likely to be displaced from their pre-insertion, evenly spaced positions around transformer core  160 . In addition, it is possible that the movement of such winding may be unnoticed because of the tight fit and corresponding limited visibility. 
         [0056]    It should be noted that channels with relatively narrow depth will aid in the manufacture tolerances. However, the use of channels with less depth (less than the radius of the wire(s) being wound, for example) may allow the wound wire(s) to migrate slightly during installation of the magnetics. Therefore, to provide greater levels of consistency, it may be beneficial to help ensure the windings do not migrate during the manufacturing process by using channels with a depth greater than the radius of the wire(s) being wound. 
         [0057]      FIGS. 19-20  illustrate the front side of an alternate embodiment a modular jack. As shown, magnetic jack  300  is a single port jack for receiving multiple Ethernet or RJ-45 type of plugs (not shown). Inasmuch as many of the components of single port magnetic jack  300  are identical to those of multi-port magnetic jack  100 , like numbers are used for like elements. Magnetic jack  300  includes a magnetic jack housing  302  made of an insulating material such as a synthetic resin and includes a single front side opening or port  303  that is configured to receive an Ethernet or RJ-45 type jack (not shown). The magnetic jack  300  is configured to be mounted on circuit board  304 . A metal or other conductive shield assembly  306  is used to surround the magnetic jack housing  302  for RF and EMI shielding purposes as well as for providing a ground reference. Shield assembly  306  is a one piece member having a rear flap  306   a  that folds down over housing  302  to fully enclose and shield the housing as is known in the art. 
         [0058]    Referring to  FIGS. 21 and 22 , subassembly module  318  includes a contact module  320  that is electrically connected to a PCB  322 . The PCB  322  is mounted to a component housing  326 , which includes magnetic circuits and filtering components. The PCB  322  includes the resistors, capacitors and any other components associated with the chokes and transformers located inside the component housing  326 , which together comprise the filtering circuitry of the magnetic jack. Contact assembly  321  provides physical and electrical interfaces, including contact terminals  328 , for connecting to an Ethernet plug. The contact module  320  is electrically connected to the PCB  322  through leads  332 , which are soldered, or electrically connected by some other means, to a row of holes  334  that are positioned along one edge  335  thereof. 
         [0059]    Referring to  FIGS. 23 and 24 , component housing  326  is a one piece member for holding magnetics  151  therein. As described above, the magnetics  151  provide impedance matching, signal shaping and conditioning, high voltage isolation and common-mode noise reduction. The structure of the transformer and choke subassemblies  152  are identical to those described above and shall not be repeated. However, rather than inserting the transformer and choke subassemblies  152  into the sides of component housings  126  as described above, the transformer and choke subassemblies  152  are inserted through an opening  344  in the bottom of component housing  326 . The wires  183  associated with the transformer and choke subassemblies  152  are soldered to electrically conductive metal pins  354  as described above. After the leads are soldered, epoxy may be inserted into the opening  344  if desired. Finally, the PCB  322  is mounted on the component housing  326  to complete the assembly of contact module  320  and such module may be inserted into magnetic jack housing  302 . 
         [0060]    The disclosure provided herein describes features in terms of preferred and exemplary embodiments thereof. Numerous other embodiments, modifications and variations within the scope and spirit of the appended claims will occur to persons of ordinary skill in the art from a review of this disclosure.