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Crossover T1 Cable

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The below diagram is not quite correct. For industry references, see instead: T1 Crossover Cable

When I got my Adtran TSU 600 unit for use with a Digium T100P card, it shipped with a straight-through T1 Cable, however, this setup (and I’d assume all using T100P) requires a crossover cable. Instead of destroying the cable that it came with, I created my own using standard Cat-5 cable used for ethernet. I had a spool available and a few ends, so I cut off a few feet (the TSU and server are in a rack mount) and got a couple ends.

It’s also useful to check if the configuration for a TE4xxP card is correct or to check if the card is functioning.

The wiring is:

  • 1 — 4
  • 2 — 5
  • 4 — 1
  • 5 — 2
Crossover T1 Cable

Side 1 (left is cable end, clip underneath):

  • Pin 1: Orange Striped
  • Pin 2: Orange Solid
  • Pin 3: none
  • Pin 4: Blue Solid
  • Pin 5: Blue Striped
  • Pin 6: none
  • Pin 7: none
  • Pin 8: none

Side 2 (left is cable end, clip underneath):

  • Pin 1: Blue Solid
  • Pin 2: Blue Striped
  • Pin 3: none
  • Pin 4: Orange Striped
  • Pin 5: Orange Solid
  • Pin 6: none
  • Pin 7: none
  • Pin 8: none

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