User's Manual

DRAFT 4
86 Installation TB9400 Installation and Operation Manual
© Tait Electronics Limited September 2011
5.6.7 Connecting a 1 PPS Source
A 1 PPS signal is required for simulcast base stations. This and the external
frequency reference can be provided, for example, by a Tait T801-4
Frequency Reference. For more information, see the T801-4 Installation
and Operation Manual (MBA-00033-xx).
Use a 50 Ω coaxial cable (RG58 or RG223) to connect the source to the
base station’s 1 PPS input. You can daisy-chain up to six base stations using
T-junctions. We recommend that the cable length between the first and last
load is kept to a minimum. This will reduce any propagation variation
between base stations. The maximum overall cable length is 30 m. Terminate
the last connection with a 50 Ω resistor, otherwise reflections of the 1 PPS
pulse may occur.
5.6.8 Ethernet Connection
The RJ-45 socket on the reciter’s rear panel provides the 10BASE-T or
100BASE-T Ethernet connection to the other devices in the network. Use
Cat-5 cable to connect this socket to the TaitNet P25 Network via a router
or switch.
If necessary, refer to “Ethernet Connector” on page 109 for a list of Ethernet
connection pin allocations.
Figure 5.11 Daisy-chaining a 1 PPS input
The longest length of cable must be between
the source and the first base station
use short lengths of cable
between each base station
maximum of six base station
loads on one 1 PPS output
50 Ω termination