摘要:
A method and apparatus for monitoring telecommunication lines. A switch is disposed between the telecommunication lines to be monitored and a jack which is connectable to a signal monitoring device. The switch is positionable into a neutral position for permitting connection of the signal monitoring device to the jack and at least a second position where the signal monitoring device may monitor the signals of the telecommunication lines.
摘要:
A cable retainer assembly for retaining cables in a cable trough includes an elongated member that can be detached and secured to a trough. The member has a receptacle disposed at least partially along a length of the member. In one embodiment, the receptacle is a U-shaped channel which extends along the length of the elongated member. A retainer includes a flange that can be inserted in the receptacle and is sidable along the length of the receptacle. A second channel is provided for detachably securing the elongated member to a cable trough. A third channel may be provided on a front face of the elongated member for retaining a designation chart. The chart may be marked to indicate cable designations.
摘要:
A coaxial jack with an internal switch mechanism includes a cylindrical shell having an axial front opening, and an elongate center conductor supported coaxially inside the shell. A back end of an elongate resilient switch contact is fixed by a switch contact support at a back portion of the shell on one side of the shell axis. The switch contact extends inside the shell toward the front opening at a certain inclination and has a free end located on a side of the shell axis opposite the one side. The switch contact is configured and positioned to make an electrical connection with the center conductor in the absence of a mating plug. An elongate actuator is supported on the inner periphery of the shell and has an engaging part that protrudes into a defined plug travel path inside the shell. The engaging part is configured to cause the free end of the switch contact to deflect by an amount sufficient to break the electrical connection between the contact and the center conductor when a mating plug travels into the shell and displaces the engaging part of the actuator.
摘要:
A connection switch jack has first and second sets of pins, and a set of spring contacts for connecting the first and second sets of pins when the spring contacts are in a normally closed position. The jack has a receptacle for receiving a plug having a plurality of plug contacts, wherein receipt of the plug connects corresponding plug contacts to selected pins of the first set of pins via the spring contacts and then moves the switch off of the normally closed position to break the contact between the first and second sets of pins.
摘要:
A printed circuit board that reduces parasitic effects on devices mounted thereon. The printed circuit board comprises a top layer and a bottom layer of a first insulating material having a first dielectric constant. The layers are configured to form holes whereby each of the holes has a first part extending through the top layer and a second part extending through the bottom layer. The bottom layer is further configured to comprise a second insulating material having a second dielectric constant, which second insulating material surrounds the second part of the hole. The devices mounted onto the printed circuit board have pins that extend through the holes. When the second dielectric constant is less than the first dielectric constant, the parasitic effects on the pins of the mounted devices are reduced.