Cisco 7000 Hardware Installation And Maintenance page 221

Figure 5-20 Location of Jumper J6 on the E1 Port Adapter—Partial View
DS2
T1
T2
J6
3 2 1
Spare
jumpers
E1 port adapter
Table 5-11 E1 Port Adapter Jumper J6 Settings and Functions
Pins and Impedance Function
1 and 2 for 120 ohm Controls capacitive coupling for either 120-ohm or 75-ohm operation. An installed
2 and 3 for 75 ohm jumper directly connects the Rx shield to chassis ground.
To prevent problems with the E1 interface and to reduce the potential for injury, jumper J6
Warning
should be installed by trained service personnel only. For either impedance option, a jumper installed
at J6 bypasses the AC-decoupling capacitor to ground, thereby coupling the interface directly to AC.
This is a setting that could pose a risk of severe injury. By default and for safety, J6 has no jumper
installed.
After you set jumper J6, proceed to the section "Removing and Replacing MIP Port Adapters" in
this chapter.
CR3
CR1
J7
Cable
connector
Jumper
J6
Installing and Configuring Processor Modules
Maintenance 5-217