Owner`s manual

MT56DSU-R Owner's Manual
40
4.3.6 DSU Back-to-Back Test
This test lets you connect two MT56DSU-Rs with a back-to-back
cable to verify proper DSU operation. Using a DSU that is known to
be operational, you can test a second DSU that is suspect.
1. Obtain a DSU Back-to-Back cable (CADSURBB) from Multi-
Tech, or assemble one. Refer to Appendix B for instructions on
building the Back-to-Back cable .
2. On the good DSU board, set DIP switch #9 to the down
position.
3. Set one DSU to internal clocking and the other DSU to DDS
clocking.
4. Plug the Back-to-Back Cable into the line backplane connector
on each DSU.
5. If you send data from your DTE, it should be "looped back" to
your DTE. If you have access to a Bit Error Rate Tester, this
can be used in place of the DTE.
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