Audible Ring Back Signal - Nortel DMS-100 Series General Description Manual

Audible ring back signal

Audible ring back indicates to the calling party the called party is being rung.
For all calls, the ring back signal is generated by the tone card in the peripheral
unit hosting the calling party.
The ring back signal in the DMS-100 switch operates on a 6-s cycle, which is
similar to but independent of the ringing cycle. The ring back signal is close
to, but not synchronized with, the DMS-100 switch ringing cycle. An
illustration of the timing between the audible ringing signal and the power
ringing signal is illustrated in the following figures.
Note: Because audible ringing and power ringing are driven by two
different peripherals, the two ringing cycles are not synchronized.
Figure 1-29 Timing of audible and power ringing signals - immediate ringing
disabled
Power ring
Audible ring
1 ringing cycle
2 s
0 1 2 3 4 5 6 7 8
Ring request
Audible ring starts
0 1 2 3 4 5 6 7 8
2 s
1 audible ring back cycle
DMS-100 Family DMS-100 Ringing System BASE15 and up
DMS-100 ringing overview 1-41
91011 0 1 2 3 4 5
Power ring
starts
91011 0 1 2 3 4 5
6 7 8 9 1011
6 7 8 9 1011