NEC Univerge SV8100 Features And Specifications Manual page 1300

Issue 12.0
To receive a Reverse Voice Over Call while busy:
1. Press the Voice Over key (Program 15-07 or SC 751: 48).

The voice over key allows you to switch back and forth between the initial call and the Reverse Voice Over Call.
To return to your initial caller:
1. Press the Reverse Voice Over key again.

If the co-worker you call hangs up, you return to the initial call automatically.
When the telephone is idle:
To place a call to your Reverse Voice Over destination:
1. Press your Reverse Voice Over key (Program 15-07 or SC 751: 47 + destination extension).
 You can optionally lift the handset after this step for privacy.
2 - 1270
UNIVERGE SV8100
Reverse Voice Over