Abstract: EMI suppression technique that pseudorandomizes the positive or negative going transitions that are used to represent one binary state in a transmitted digital signal such as in an MTL-3 data format. By pseudorandomizing the selection of these transitions, substantial spreading of the spectral energy occurs. Descrambling need not occur since each transition is recognized as the encoded binary state. Thus, the data sender can encode the data and suppress EMI without any changes to the receiver's equipment.

Abstract: An apparatus for monitoring and testing a twisted pair, particularly useful for an Ethernet network. First and second DC currents alternated with one another are applied to both ends of the line, asynchronously. By monitoring the potential on the line, a determination is made as to the condition of the line. For example, shorted, crossed, improperly terminated or open conditions can be detected. A visual indication of the condition of the line is provided and additionally, the visual indication provides an indication of the traffic level in the network.

Abstract: An amplifier for use with a twisted pair LAN. Each stage of the amplifier provides amplification including higher frequency emphasis for a predetermined length of line. The correct number of stages are automatically activated within the amplifier. Thus a singly configured amplifier may be used for different line lengths.