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TN556 ISDN BRI 4-Wire Interfaces

by Avaya

Availability: Yes
$59.00 Sale Price:
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TN556B - TN556D ISDN BRI 4-WIre Interface

Provides 12-ports connecting to ISDN-BRI terminals. Each port uses TXT, TXR, PXT, PXR signal leads. Range up to 3300 ft. maximum from the system to the voice terminal.


  • Ports connection to ISDN-BRI terminals: 12
  • Signal leads: TXT, TXR, PXT, and PXR
  • Up to 8 ports can be used for ASAI links
  • 2 B-channels
  • 1 D-channel
  • Range up to 3300 ft.
  • Compatible with Definity R7 or late
  • Requires a packet control circuit pack (TN778) if using R6si systems
  • One Year Warranty Included with Extended Warranty Options at Low Prices!

Package Includes

  • TN556D ISDN BRI 4-WIre Interface
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