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TN556B ISDN BRI 4-Wire Interface

Like New: $29.99
This product is eligible for 2 Year Platinum Protection!

TN556B Features

  • Provides 12-Ports connecting to ISDN-BRI terminals
  • Each port has TXT, TXR, PXT, and PXR signal leads
  • Up to 8 ports can be used for adjunct switch application interface (ASAI) links
  • Each port operates at 192 kbps per second and has 2 B-channels and 1 D-channel
  • Requires a packet control circuit pack (TN778) when used in R6si systems or packet bus-equipped R6vs systems
  • Range of up to 3300 ft. maximum from the system to the voice terminal
  • Can connect 24 terminals where each terminal uses 1 B-channel and shares the D-channel
    Compatible with Definity R7 or later

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