The Tieline POTS G5 module can be used in the codec to stream high quality audio over a POTS (PSTN) phone line. The codec has two module slots available and it is possible to insert one or two POTS G5 modules, or a mix of POTS G5 and ISDN G5 modules as required. The Tieline Music algorithm can deliver 15 kHz quality bi-directional audio at bit rates as low as 24kbps over a POTS connection.

 

Modem Negotiation and Line Quality

The codec can send and receive high-speed digital information over a standard POTS telephone line via the modem in the POTS G5 module.

 

G5 POTS modems initially attempt to establish a link at the lowest Max Bit rate setting configured in the two modules being connected. If the POTS line doesn't support this bit rate, the modems will attempt to connect at the highest possible bit rate to suit the prevailing line quality at each end of the link. The modem then perform a process called ‘training’, during which the codecs at each end of the link analyze the line. The codecs will then 'renegotiate' the link downwards to the highest possible bit rate where line quality is greater than 70%.

 

The POTS G5 module contains a SmartDAA™ (Smart Data Access Arrangement) line interface, which isolates the modem from voltages on phone lines. It is important to select the correct country in the codec from which you are dialing. This allows the SmartDAA to automatically adjust for the line voltage present in that country.

 

 

Connecting to G3 Codecs using POTS

The codec will successfully connect to Tieline Commander G3 and i-Mix G3 codecs over POTS. These Tieline G3 codecs may use:

 

•POTS modules (older superseded version)

•POTS G3 modules (current version)

 

Connecting to POTS G3 Modules

POTS G3 modules operate in the same way as POTS G5 modules when connecting, e.g. they establish a link at the default bit rate of 28.8kbps and then 'renegotiate' the link downwards to the highest possible bit rate where line quality is greater than 70%.

 

Connecting to Legacy POTS Modules in G3 Codecs

These modules have slightly different characteristics when connecting. When dialing from a POTS G5 module to these older POTS modules the codecs will attempt to connect initially at 19.2kbps. If line quality is above 80% at this bit rate then the codec will ‘retrain’ the connection up to a maximum of 28,800bps (depending on modem handshaking). The codec will then renegotiate the link downwards to the highest possible bit rate where line quality is greater than 70%.

 

How to Configure POTS G5 Codec Connections

To configure the codec to dial using POTS for the first time:

 

1.Ensure that the correct country setting is configured in your codec via Settings > System > Country. This ensures the correct settings are used by the codec when making POTS connections.

2.When dialing between two Tieline codecs you normally only need to configure a POTS dialing program via Connect > POTS.

 

Other more advanced settings can also be configured:

 

1.Select Settings > Modules > [Select POTS Module] to adjust POTS module settings specific to your codec site. See Configure POTS Module Settings for more information. See Configuring POTS Modules to adjust settings using the Java Toolbox Web-GUI, or click here to adjust settings using the HTML5 Toolbox Web-GUI.

2.If you are connecting to non-Tieline codecs you may need to create an answering "Config" via Settings > Answering > POTS Answer Configs > [Select POTS Config], which will determine the module used and relevant settings for answering a non-Tieline POTS call. See Configure POTS Module Answering for more information. See Configuring POTS Answering to adjust settings using the Java Toolbox Web-GUI, or click here to adjust settings using the HTML5 Toolbox Web-GUI.

 

 

Making Analog Phone (Voice) Calls

All POTS G5 modules are capable of making analog voice calls. It may be necessary to make an analog call to dial a telephone hybrid, or to use for communications, or because there is no Tieline codec at the other end of the link. Remember analog voice calls are only 3 kHz audio quality. To select analog phone answering mode in a POTS G5 module navigate to Settings > Modules > POTS > Answer Mode [Analog phone].