7
Introduction
The 960 HF Telephone interconnect is designed to provide users on a HF network full interconnection with the
international telephone network. It is designed to be operated as a completely automatic facility with no requirement
for human operator supervision. A high level of security is incorporated to eliminate system abuse.
This manual is divided into two sections, the first part of the manual gives a brief system overview and details the
operation of the 960 telephone interconnect assuming the 960 has already been setup by a system supervisor. The
second part of the manual details the 960 setup procedures.
System Overview
The 960 telephone interconnect will make your HF network stations extensions of the international telephone
network.
The 960 telephone interconnect provides a fully automated interface between the international telephone network
and a HF network. Stations in a HF network equipped with selective call systems based on CCIR 493 can call up
to 98 numbers that can be stored in the 960 telephone interconnect. Stations fitted with a “Telcall” facility, based on
selective call format CCIR 493, can direct dial any telephone number on the international telephone network.
Telephone subscribers can dial into the 960 telephone interconnect from anywhere on the international telephone
network and call any station on the HF network.
The Barrett 960 telephone interconnect provides full network management facilities including multiple telephone
access levels for HF stations, call logging and remote supervision by dial up computer links
Operation
After switching on, the 960 performs a series of internal checks and displays important system information on the
front panel display. If Levels 2 or 3 are fitted, additional information is sent to the printer.
Automatic mode overview
In automatic mode the 960 HF telephone interconnect will:-
Scan all channels programmed for scan looking for an incoming Selcall or Telcall from a HF network station.
On receipt of a Selcall or Telcall, the 960 checks that the station calling is registered in the database and has
the required access privilege programmed by the system supervisor, if so it then initiates a telephone call and
connects the telephone party with the HF station.
Return to scan when the call is complete.
Answer an incoming telephone call, prompt the telephone caller with recorded instructions on how to select
a channel and how to send a Selcall to connect to a user on the HF network.
Periodic beacons if selected, will be sent on all channels to help the user determine if a particular channel is
suitable for communication at the required time. A beacon signal can also be requested from the transceiver
being called to check if a particular channel is suitable for use at the required time.
In the case of Level 2 or Level 3 960's - log all calls from both the telephone network and the HF network,
either sending the information to a local printer or in the case of a Level 3 960 storing the information internally,
ready to be interrogated by an external PC, loaded with 960 online supervisory software. A standard MODEM
is used to connect to the 960 via the telephone network.
