Types of ALLC service offered:

• Private Wire 
• Data Circuit 
• Hotline

Specifications for ALLC Service

The relevant specifications for a Private Wire are:

 a. Line Loss

 The nominal loss is not greater than 28dB. The reference frequency used is 1004 Hz.

 b. Voice Frequency Band 

 The service provides a permanent controlled voice frequency band circuit in the range of 0.3KHz to 3.4KHz

The relevant specifications for a Data Circuit are:

 a. Line Loss

 The nominal line loss is not greater than 23 dB for a national circuit, and not greater than 15 dB for the national section of an international leased circuit (ie. from the Customer's premises to SingTel's International Gateway). The reference frequency used is 1004 Hz.

 b. Psophometric Noise

 The level of psophometric noise without presence of tone is better than -50 dBm, where applicable, measured with one end terminated at 600 ohms.

 c. Voice Frequency Band

 The service provides a permanent controlled voice frequency band circuit in the range of 0.3KHz to 3.4KHz for data transmission.

The relevant specifications for a Hotline are:

 a. The nominal line loss of a hotline is not greater than 28 dB. The reference frequency used is 1004 Hz.

 b. The service provides a permanent controlled voice frequency band circuit in the range of 0.3KHz to 3.4KHz.

Service Applications

Private Wire :

Available as 2-wire or 4-wire options. Private Wire is used for voice, telegraph, and alarms or telemetry devices. 

Data Circuit :

Available as 2-wire or 4-wire options. Data Circuit can be used for data transmission when used with analogue modem.

Hotline :

Hotline, also known as a Central Battery (CB) line, provides a 2-wire non-dial dedicated speech link between any two points within Singapore island. 

Product feature specs as follows :

1) Hotline is a permanent physical connection between two valid business locations which is connected to analogue phones (analogue phones are supplied by the customers)

2) The Hotline service enables the called party’s telephone to ring when the calling party lifts up the handset

3) Connection between the two parties will be established when the called party’s handset is picked up during ringing. The ringing will stop when the call is established

4) Both parties must replace the handsets for the hotline to be in a ready-to-call condition again

If the call is not answered, the ringing will stop after the called party replaces the handset.