•	If the callback ring is not answered within 10 seconds, callback is canceled.
•	If the extension hears a busy tone before dialing the telephone number, only the CO line or CO line group is reserved. After answering the callback ring, the extension should dial the telephone number.
•	An extension can set only one Automatic Callback Busy. The last setting is effective.
•	Multiple extension users can set this feature for the same CO line at the same time. However, a maximum of four extension users can set this feature to one extension.
•	The priority of the callback is the setting order.
•	This feature cannot be used for calls to a Voice Processing System (VPS).

User Manual

1.2.4 When the Dialed Line is Busy or There is No Answer

Allows an extension user to interrupt an existing call to establish a three-party conference call.

Executive Busy Override Deny
It is possible for extension users to prevent their calls from being interrupted by another extension user.

•

Class of Service (COS) programming determines extension users who can use the Executive Busy Override (

Executive Busy Override [505]) and set the Executive Busy Override Deny mode (

Executive Busy Override Deny [506]).

•

This feature will not function when the busy extension:

a)	Has set Executive Busy Override Deny or Data Line Security ( 1.10.5 Data Line Security).
b)	Is being monitored by another extension ( 1.7.3 Call Monitor).
c)	Is receiving an Off-hook Call Announcement (OHCA) ( 1.7.4.3 Off-hook Call Announcement (OHCA)) or Whisper OHCA ( 1.7.4.4 Whisper OHCA).
d)	Is on a conference call ( 1.13.1 Conference Features).
e)	Is on a doorphone call ( 1.15.1 Doorphone Call).
f)	Is using Live Call Screening (LCS) or Two-way Record ( 1.21.2 Voice Mail DPT (Digital) Integration).
g)	Has a call on a consultation hold ( 1.12.5 Consultation Hold).

•

This feature is not available for a CO-to-CO line call via Direct Inward System Access (DISA) (

1.15.6 Direct Inward System Access (DISA)).

User Manual

Allows an extension user to listen to a busy extension user's existing conversation. The user can hear the conversation but will not be heard. If desired, the monitoring user can interrupt the call to establish a three-party conference call.

•

Class of Service (COS) programming determines extension users who can use this feature.

•

This feature is available only when the busy extension is in a conversation with another extension or outside party.

•

This feature will not function when the busy extension:

a)	Has set Executive Busy Override Deny ( 1.7.2 Executive Busy Override) or Data Line Security ( 1.10.5 Data Line Security).
b)	Is receiving an Off-hook Call Announcement (OHCA) ( 1.7.4.3 Off-hook Call Announcement (OHCA)) or Whisper OHCA ( 1.7.4.4 Whisper OHCA).
c)	Is on a conference call ( 1.13.1 Conference Features).
d)	Is on a doorphone call ( 1.15.1 Doorphone Call).
e)	Is using Live Call Screening (LCS) or Two-way Record ( 1.21.2 Voice Mail DPT (Digital) Integration).
f)	Has a call on a consultation hold ( 1.12.5 Consultation Hold).

•

This feature stops when the busy extension user presses the following buttons during a conversation (

1.18.1 Fixed Buttons,

1.18.2 Flexible Buttons):

—

FLASH/RECALL button

—

HOLD button

—

TRANSFER button

—

CONF (Conference) button

—

DSS button

—

EFA button

—

Two-way Record button

—

Two-way Transfer button

—

One-touch Two-way Transfer button

—

Voice Mail (VM) Transfer button

User Manual

1.2.4 When the Dialed Line is Busy or There is No Answer

When attempting to call a busy extension (i.e., an extension that is ringing or having a conversation), an extension user can send a call waiting indication to the busy extension (Call Waiting). The method of notification received depends on the called extension's personal setting and the telephone type:

Notification

Description

Details in

Call Waiting Tone

Sends a call waiting tone to the busy extension.

• 1.7.4.2 Call Waiting Tone

Off-hook Call Announcement (OHCA)

Allows the caller to talk with the busy extension using the built-in speaker and microphone of the called extension, while the existing call is continued using the handset.

• 1.7.4.3 Off-hook Call Announcement (OHCA)

Whisper OHCA

Allows the caller to speak to the busy extension through the handset.

• 1.7.4.4 Whisper OHCA

•

Each extension user can choose to receive call waiting tones, OHCA, Whisper OHCA, or none of these.

•

OHCA and Whisper OHCA are enabled or disabled by the Class of Service (COS) of the calling extension.

•

OHCA and Whisper OHCA are not compatible with certain telephone types. In such cases, a call waiting tone will be sent to the called extension.

OHCA Mode of Calling Extension's COS

Called Extension's Call Waiting Mode

OFF

Call Waiting Tone

OHCA

Whisper OHCA

Disable

Call Waiting disabled

Call waiting tone

Enable

Call Waiting disabled

Call waiting tone

OHCA
(or Call waiting tone)

Whisper OHCA (or Call waiting tone)

•

The notification receiving methods (call waiting tone, OHCA, and Whisper OHCA) are available when the called extension is having a conversation with other party. If the extension is not having a conversation but is unavailable to receive the notification (dialing a number, for example), the calling extension will be kept waiting until the called extension becomes available. Even while waiting, the calling extension will hear a ringback tone.

•

If none of these methods of receiving notification (call waiting tone, OHCA, or Whisper OHCA) is set at the called party, the caller will hear a reorder tone after trying to send a call waiting notification.

User Manual

1.2.4 When the Dialed Line is Busy or There is No Answer

When an extension user attempts to call a busy extension (i.e., an extension that is ringing or having a conversation), a call waiting tone can be sent to the called extension to indicate another call is waiting.

•	This feature functions only if the called extension has activated call waiting. If it is activated, the calling extension will hear a ringback tone.
•	One of two call waiting tones can be selected (Tone 1 or Tone 2) through personal programming (Call Waiting Tone Type Selection).

User Manual

3.1.2 Settings on the Programming Mode

An extension user can talk with a busy extension through the built-in speaker and microphone of the called party's proprietary telephone (PT). If the existing call is using a handset, a second conversation is made using the speakerphone and microphone so that the called extension can talk to both parties.

•

Class of Service (COS) programming determines which extensions can use this feature.

•

This feature is available when the called extension uses one of the following telephones:

—

KX-T7625, KX-T7630, KX-T7633, KX-T7636

—

KX-T7436

—

KX-T7235

•

Off-hook Call Announcement (OHCA) cannot be used when

(a)

The OHCA mode of the caller's COS is set to "Disable".

(b)

The called extension's telephone is not compatible with OHCA.

(c)

The called extension is a digital proprietary telephone (DPT) which is connected via a USB Module to a computer running PC Console or PC Phone.

In these cases, a call waiting tone is sent to the called extension. (

1.7.4.2 Call Waiting Tone)

•

If an extension user makes an OHCA call while the called extension has placed an intercom call on hold, the calling extension will hear a ringback tone. The INTERCOM button on the called extension will flash to show another call is waiting.

•

While an extension is receiving an OHCA, if the extension user places the current CO line call on hold or transfers the current intercom call or CO line call, the OHCA will become disabled and the calling extension will hear a ringback tone.

•

While an extension is receiving an OHCA, if the extension user places the current intercom call on hold, the called extension can talk to the calling extension through the handset.

An extension user can speak to a busy extension through the handset.

•

Class of Service (COS) programming determines which extensions can use this feature.

•

This feature is available when the calling and called extension use one of the following telephones:

—

KX-T7600 series

—

KX-T7400 series

•

If the Whisper OHCA feature cannot be used due to COS or telephone type, a call waiting tone will be sent to the called extension. (

1.7.4.2 Call Waiting Tone)

•

If the called extension is not a KX-T7600 or KX-T7400 series telephone but forces Whisper OHCA, the announcement may be heard by both parties.

•

It is possible to enable Whisper OHCA on any telephone, however, it may not function properly. (The caller's voice may be heard by both callers, for example.)

•

If an extension user makes a Whisper OHCA call while the called extension has placed an intercom call on hold, the calling extension will hear a ringback tone and the INTERCOM button on the called extension will flash to show another call is waiting.

•

While an extension is receiving a Whisper OHCA, if the extension user places the current CO line call on hold or transfers the current intercom call or CO line call, the Whisper OHCA will become disabled and the calling extension will hear a ringback tone.

•

While an extension is receiving a Whisper OHCA, if the extension user places the current intercom call on hold, the called extension can talk to the calling extension through the handset.