Tait TB9100, Инструкция по установке и эксплуатации

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58 Installation TB9100 Installation and Operation Manual
© Tait Electronics Limited May 2006
Coaxial Relay
Important
When the base station is used in simplex mode using a sin-
gle antenna with a coaxial changeover relay, the isolation of
this relay
must be > 40dB. The relay operating time must
be < 20ms.
To prevent damage to the base station, the relay must not switch whilst the
base station is transmitting, and the tranmsitter must not operate whilst the
relay is switched to the receiver.
System Interface
The reciter is fitted with industry-standard sockets which provide the
connections for the digital and analog lines, and the serial communication
link.
Figure 4.8 on page 52 shows the position of the sockets on the rear of
the reciter. Each socket visible from the reciter will be clearly labeled to
ensure proper connection.
Digital Line
The RJ-45 socket labeled ETH provides the Ethernet connection to the
other devices in the network. The 10BASE-T ethernet uses Cat-5 cable and
RJ-45 sockets to connect the base station to the network via a hub or router.
Refer to “Digital Interface Connection” on page 124 for a list of ethernet
connection pin allocations.
Analog Line
The RJ-45 socket labeled AUD provides the direct audio connection to a
local or remote dispatcher. This also provides a basic E&M signaling
interface. Refer to
“Analog Interface Connection” on page 123 for a list of
the analog connection pin allocations.
Important
The analog RJ-45 socket is keyed to ensure that the correct
cable (one with a keyed plug) is connected. If the analog
cable were to be connected to the digital RJ-45 socket, the
potentially high voltages on the E&M lines would damage
the ethernet interface.
Before connecting up any E & M or 4-wire audio circuit,
consult the Network Installation Guide for information on
circuit design and interface protection. On the E & M
circuit, the DC current flow must not exceed 150 mA
under any conditions. There must also be sufficient
suppression to absorb any inductive spikes. If DC is applied
to the 4 wire audio lines, it should also be limited to 150
mA. The nominal voltage should not exceed 48 V and the
peak voltage must never exceed 58V.