Hello and thank you for posting to our forum,
The best way to test calls in/out the FXO port is by using a Test Set with analog capabilities. This way the Test Set can act like the Central Office and will send and receive calls out the FXO port. Another way would be to use an ADTRAN Atlas unit or 2 Channel Banks to interface with the FXO port and switch calls back and forth.
Once you have the equipment connected to the FXO port, you can use the show command:
"show int fxo 0/0" (or 0/1, 0/2, etc. depending on the ADTRAN unit) to check the on-hook and off-hook conditions
Let me know if you need any configuration assistance with testing.
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