Figure 4-91. Vf subscriber circuit loop-back, fault isolation flow chart (sheet 1 of 2)

TM 11-5895-1012-10

(15) After the fault has been cleared, remove any

patches which have been established and complete sta-

tion records in accordance with established proce-

dures.

c. Fault Isolation of a VF Subscriber Circuit by the

Loop-Back Method. This procedure followed is outlined

in flow-chart fashion in figure 4-9. The Technical

Controller is notified by a local subscriber that the cir-

send point of the same channel under test at the equal

cuit level is not correct. A spare channel is available

level patch panel.

and the circuit is patched over onto the spare circuit so

(3) The local Technical Controller inputs a 1

that the normal path can be available for out-of-service

Hz test tone on the send circuit at a level of 0 dBm at

testing. The basic procedure is to clear the local station

the equal level patch panel. The same test tone should

Vf subscriber circuit loop-back, fault isolation flow chart (sheet 1 of 2)