On-line test method
1. select a traffic channel
2. find the port on the DDF corresponding to this channel
3. Connect one end of the test cable with the on-line test
connector of the port on the DDF and the other end with the
on-line test interface of the BER tester
4. set the BER tester, please refer to its usage instructions
5. there should be no bit error in 24 hours
Test of Bit Errors
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