Troubleshooting the Communication Channel

TM11-5895-932-14&P

lines, require a special item of test equipment, a bit

AMME to the remote terminal equipment has

error rate tester (BERT). It generates a known

several functional areas that can degrade com-

digital signal that can be transmitted to itself for the

munications. The functional areas are shown on the

purpose of determining any errors created in the

block diagram. figure 4-1. The degradation of

transmission. The number of errors are received by

communication is a more significant problem to the

the BERT and totalized and the total provides an

repairman that the complete failure which is usually

indication of the quality of the transmission medium

quite easily pinpointed to a single defective

or circuits being tested. That is, a high number of

equipment. In the communication chain shown, a

errors represents a transmission through faulty

diagnostic program can be run on the AMME and

circuits whereas a low number of errors recorded

the terminal equipment. to determine whether they

represents normal transmission.

are degrading the system. The transmission system,

represented by the modems and communication

4-5