5.8.2. Dial Tone, Proceed-to-Send Signal on Outgoing Seizure 
There are users who wait for a proceed-to-send signal (usually a dial
tone) after the trunk group code. We recommend giving up this type of
dialing and continuing to dial immediately.
Using different parameters and settings, you can have the system request
that the user continue dialing.
- After the user dials the trunk access code, the system applies a tone even if it has
not
found a circuit:
AMO ZAND: TYPE=ALLDATA, CODTN=YES;
- Using LDPLN, you can configure the digit pattern so that the dial tone is applied
at any
position in the dialing. Here it is also the case that the system has not yet searched
for
(let alone seized) the circuit. You can also administer several dial tones here. Example
for
applying the dial tone after the user has dialed the code 528:
ADD-LDPLN:LDP=528-W-X,LROUTE=228,LAUTH=1;