Specifications

Chapter 7 Battery Reversal FXS/DPO
7-9
3. As an aid to network technicians troubleshooting audio problems, 4 seconds of continuous
ringback tone are also sent toward the T1 network.
4. After the 4 seconds of continuous ringback tone, the FXS channel will “busy out” toward the T1
network side.
Note: Each channel test switch can provide ringing during Trunk Processing (or even when the
T1 line is disconnected).
SELF TEST LOOPBACKS
If a Self-Test is in progress and Switch A is ON, setting a channel test switch to the ON position should
have the following result:
The affected channel receives 4 seconds of continuous ringing voltage (85 V) and the LED for that
particular channel turns RED. This allows a technician to ring the telephone and verify audio tone when it
is answered.
Note: During Self Test, a RED channel LED does not indicate a problem.