NEC DS1000 Feature Handbook page 101

Trunk (Line) Queuing and Callback
To queue for a busy line:
1. Press line key for busy line.
OR
Press
(e.g., 401 for line 1).
2. Dial
3. When the line becomes free, you automatically connect.
place your call again.
To leave a Line Callback for a busy line:
1. Press line key for busy line.
OR
Press
(e.g., 401 for line 1).
2. Dial
3. When the line becomes free, the system automatically
calls you back.
from the outside line.
system cancels the Callback.
and dial the line's Direct Line Access code
; do not hang up.
When you hear dial tone from the line, you can
and dial the line's Direct Line Access code
CLBK
or press
If you answer within 4 rings, you hear dial tone
If you don't answer the Callback ring, your phone
, then hang up.
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