Globalstar Product Management – Technical Support

The Globalstar fixed phones, GSP-2900 and FAU200, provide a standard POTS (Plain Old Telephone Service) interface which can be used as an outgoing “TRUNK” line for a PBX.    There are two standardized signaling methods which are used by PBXs to manage a POTS trunk line — “Loop Start” and “Ground Start”.

• Loop Start supervision is a supervisory signal from an end terminal to a switch in response to completing the loop path
• Ground Start is a signaling method from a terminal to a switch where one side of a cable pair is temporarily grounded

.

Requirements for PBX Configuration and Compatibility:.

• In order to use a Globalstar fixed phone as an analog trunk line on a PBX, the Globalstar tip/ring line must be connected to an analog FXO Loop Start voice port on the PBX.
• This is because the Globalstar “fixed phone” products, GSP-2900 and FAU200, only support Loop Start.

.

Globalstar Fixed Phone Features to Support PBX:

Loop Start and Ground Start

• The Globalstar GSP-2900 and FAU200 fixed phones detect Loop Start in accordance with BS 6305 and BS 6317.
• Ground Start is not supported

.

Additional Features
The GSP-2900 and FAU200 fixed phones provide the following signaling methods to support the PBX:

• Two-wire (tip/ring) Loop calling unguarded clearing protocol
• Loop Current Break (clear backwards)
  • When a call is unsuccessful or cleared down by the far end, the fixed phone line interface delivers an appropriate tone (as determined by the network) followed by a break of the loop current.
• Called Subscriber Answer (CSA) indication using Line Reversal
• Immediate Ringing, used instead of ground start to reduce glare (call collision)
• Call collision events are handled in a manner that gives priority to outgoing phone calls

Keywords:  Globalstar PBX compatibility GSP-2900 RAU GSP-2800 GSP-2400 FAU200 FAU-200