Specifications

Trunks 53

Echo cancel when bridged

Enables or disables echo cancellation during a bridged TDM call. In principle, TDM bridged calls should not

require echo cancellation, but often times audio performance is improved with this option enabled. Default:

Echo Training

In some cases, the echo canceller doesn't train quickly enough and there is echo at the beginning of the call

which then quickly fades out. Enabling echo training will cause Asterisk to briefly mute the channel, send an

impulse, and use the impulse response to pre-train the echo canceller so it can start out with a much closer

idea of the actual echo. However, the characteristics of some trunks may change as the endpoint's become

connected and, if there is a considerable delay between the circuit being 'up' and the endpoint's being

finalised, the training impulse may measure the characteristics of the open trunk rather than the completed

circuit. Accordingly you may either specify a value between 10ms and 4000ms to delay before starting the

impulse response process or 'yes', which equates to 400ms. Default: undefined

Rxgain

Adjusts receive gain. This can be used to raise or lower the incoming volume to compensate for hardware

differences. You specify gain as a decimal number from -100 to 100 representing 100% to 100% of capacity.

Default value: 0.0

Txgain

Adjusts transmit gain. This can be used to raise or lower the outgoing volume to compensate for hardware

differences. Takes the same type of argument as rxgain. Default: 0.0

Call Logging Options

Asterisk normally generates Call Detail Records (CDR), being a log or database of the calls made through

Asterisk. This data can be used for Automated Machine Accounting (AMA).

Account Code

Sets the data for the "account code" field in the CDR for calls placed from this channel. The account code

may be any alphanumeric string.

AMA flags

Sets the AMA flags, affecting the categorization of entries in the call detail records. Possible values are:

* default: Let the CDR system use its default value.

* omit: Do not record calls.

* billing: Mark the entry for billing

* documentation: Mark the entry for documentation.

6.1.2.1.2 Zaptel

The zaptel.conf file is where you configure the TDM-specific interface parameters required for ZAPTEL

card(s).

Span number

Span number set which span this trunk is to use.

Span timing

Span timing sets where is zaptel going to obtain its timing from. Choices are: 0 (Telco), 1 (System) , 2 (?)

Line Build Out

Line build out sets the distance between service hardware equipment.

Framing

Framing used on this trunk.

Coding