User's Manual

Table Of Contents
TB9400 Installation and Operation Manual 125
© Tait Limited December 2013 (Draft)
outbound
Describes the direction of a signal: from a fixed station over the air
interface to an SU.
over A single transmission, which begins when a user presses PTT and ends
when the user stops pressing.
P25 Project 25. A suite of standards and requirements endorsed by the TIA and
intended for digital public safety radio communications systems.
PA The Power Amplifier is a base station module that boosts the exciter output
to the required transmit level.
PCB Printed Circuit Board.
PMU The Power Management Unit is a module in the base station that provides
power to the subrack and monitors power conditions.
preamble A well-defined signal that is transmitted at the beginning of digital P25
calls to facilitate downlink voting and to allow the transmit buffer to fill.
privileges A set of access rights to the web interface functions. There are Guest,
Maintainer, and Administrator privileges.
Project 25 A project set up by APCO (the Association of Public Safety
Communications Officials), together with other US governmental
organizations, to develop standards for interoperable digital radios to meet
the needs of public safety users.
PSTN Public Switched Telephone Network: the public telephone network.
PTT Push To Talk. The button on an SU that keys the transmitter.
QoS Quality Of Service. A router feature that gives real-time data such as voice
calls priority over other data.
receiver number A unique number assigned to the members of a channel group.
reciter A module of a base station that provides both receiver and exciter
functionality.
repeater talkaround Allows the SU user to bypass repeater operation and so communicate
directly with other SUs. While repeater talkaround is active, all