Specifications

Installation and Operation Manual Chapter 4 Diagnostics and Troubleshooting
HS-RN MP-2100/2104 Ver. 12.6, MP-4100 Ver. 2.0 4-3
4.2 Troubleshooting
The loops available on the HS-RN module provide a rapid and efficient way to
identify the general location of a fault either of the HS-RN modules connected in
a link, in the external equipment, or in the connections to the channels.
If the LOS indicator of an HS-RN channel lights, or a complaint is received
regarding the transmission of data through one of the HS-RN channels, perform
the following procedure until the problem is located. After each step, continue to
the next step only if the previously specified test has been successfully
completed.
If the problem is detected when a connection between two new users is
activated for the first time, before starting the troubleshooting procedure
described below thoroughly check the timeslot allocation, the configuration of
the two Megaplex units that provide the new connection, and the configuration
of the user's terminal equipment.
• Request the user to perform a local loopback test on the local data
equipment. If the user equipment does not receive its own signal, the
problem is in the user equipment. After correcting the problem, continue
troubleshooting as explained below.
• If the signal is not received when the remote digital loopback is activated,
activate the local main link loop on the local Megaplex unit:
 If the user equipment does not receive its own signal when the main link
loop is connected, the problem is in the local unit.
 If the signal is received when the main link local loopback is activated,
activate the remote main link loop.
If the user equipment does not receive its own signal, the problem is
either in the timeslot allocation, or in the remote unit.
4.3 Frequently Asked Questions
Q When installed in the MP-4100 chassis, do the HS-RN modules operate
exactly the same as when installed in the MP-2100/2104 chassis?
A Yes, they do. All the differences between the two module locations are
purely chassis/common logic related (command line vs menu interface,
main link vs CL.1 or I/O ports as timeslot destinations, etc). The main
module-level difference is that the bidirectional broadcast mode (BID-BRD
RX) is not available for the module operating in the Megaplex-4100 chassis.
Note