Users Manual Part 1

4.8.6
GPS Interference Avoidance
You can employ the following two strategies to mitigate against jamming signals:
• Determine a location where adequate GPS signals are available using a hand held receiver and
move the Base station GPS antenna to this location.
• Construct a shield (Cardboard Foil is adequate) to exclude the jamming signal. Locate the shield
approximately 6 cm from the antenna body and connect it to an earth point.
4.9
X.21, E1-120Ω
Cabling
A cable connects the network termination unit (NTU) and the E1/X.21 interface on the MTS Junction
Panel, see Figure 75: E1/X.21 and Ethernet Site Link Connectors on the MTS LiTE Junction Panel on
page 145 for MTS LiTE, Figure 76: E1/X.21 and Ethernet Site Link Connectors on the MTS 2 Junction
Panel on page 146 for MTS 2 and Figure 77: E1/X.21 and Ethernet Site Link Connectors on the MTS 4
Junction Panel on page 146 for MTS 4.
The E1 or X.21 (only one of them can be used) connectors on the Junction Panel are connected with
the Site Controller through an internal extension cable. For more information, see E1 and Ethernet
Cabling on page 176 and User Alarms/Controls, X.21, RGPS, and GPS Cabling on page 170 in
Interconnection and Internal Cabling on page 163.
NOTICE: Figure 76: E1/X.21 and Ethernet Site Link Connectors on the MTS 2 Junction Panel
on page 146 and Figure 77: E1/X.21 and Ethernet Site Link Connectors on the MTS 4 Junction
Panel
on page 146 depicts the newer version of the MTS Junction Panel. There may be small
differences in older configurations.
Figure 75: E1/X.21 and Ethernet Site Link Connectors on the MTS LiTE Junction Panel
X.21
Ethernet
Site Links
E1
X.21
Ethernet
Site Links
E1
X.21
Ethernet
Site Links
E1
X.21
Ethernet
Site Links
E1
6802800U74-AP
Chapter 4: Hardware Installation
145