TELSTRA is a digital transmission system, with exchange
function. There are three types of sets available: TELSTRA MASTER ISDN,
TELSTRA MASTER PSTN,and TELSTRA BASIC. For connecting the analog two-wires
sets it’s enough to add an adapting module TA-Z, that also ensures
the interface with a door-phone with 5 wires and ringer.TELSTRA system
offers up to 4 external lines with maximum 8 extensions system-sets
and 4 analog two-wires extensions The internal network that links the
sets and the modules of the system consists of a cable (BUS of the system)
on which internal and external communications in digital format can
be selected..ISDN type TELSTRA system allows: · Up to 2 ISDN
point-multipoint (S0) Basic Accesses with MSN (multiple subscriber number)
possibility and SUB orUp to 2 ISDN point-point (T0) Basic Accesses with
DDI facility· Up to 12 extensions consisting of 8 system sets
(MASTER+BASIC) and four analog sets with DTMF dialing (eg: Fax machine,
answering machine, modem)It is allowed to install two sets “TELSTRA
MASTER ISDN” or “TELSTRA MASTER PSTN” to create the
link with an external line by modulation of two analog lines or basic
access/set .The connection of the analog sets will be made through the
TA-Z module by modulating two analog interfaces/module.. The system
accepts up to two TA-Z modules. The link with a door-phone can be made
through a TA-Z module equipped with an optional door-phone board. In
this case, one of the two plugs for the standard set will not be used.The
total number of simultaneous bidirectional communications will be of
up to 5In the case of connectiong of two external lines (only one MASTER)
there are only three internal communications available ; in the case
of the maximum capacity usage (4 external lines) only one internal communication
is available. Anyway, redialing and an eventual transfer making during
an external conversation doesn’t imply an internal line
