troller should proceed as follows:
rapidly as possible.
(a) Patch the monitor teleprinter into the MON-
ITOR jack appearance of the subscriber's receive cir-
cuit at the dc equal level patch panel. A defective
Individual circuits are restored in accordance with
DLIU is indicated if perfect page copy is obtained at
their assigned restoration priority.
this point. If not proceed to (4) below.
a. R&oration of service to users can basically be ac-
(b) Temporarily replace the normal DLIU with a
complished by repairing or replacing faulty equip
spare unit through patching operations.
ment, rerouting the circuit around the disrupted seg-
(c) Request that local maintenance personnel re-
ment of the circuit by using spare facilities, or by pre-
pair the defective unit.
empting a lower priority circuit to make a higher pri-
(d) When the repaired DLIU is returned to the
ority circuit good. In order to maintain continuity of
normal channel assignment, the Technical Controller
service for all users of the DCS, the correction of
should remove any temporary patches which were
equipment should be used in lieu of preempting anoth-
made to restore service to the subscriber.
er working circuit when the time required by each
(e) Complete station records in accordance with
method is nearly the same. Where trouble in a high
priority circuit has been localized to the transmission
(4) VFCT Channel Equipment Check. If the moni-
media between two circuit end points and lower priori=
tor teleprinter connected in (3)(a) above produces gar-
ty circuitry exist between these two points, the lowest
bled page copy, the isolation procedure should con-
priority circuit(s) should be preempted if this will
tinue following the procedure outlined in b above.
restore the higher priority circuit in substantially less
(5) Distant Terminal Check. If the degraded signal
time than the other methods of restoration.
is present in the voice frequency signal ((4) above) a de-
b. To assist the Technical Controller in visualizing
fect in the VFCT equipment at a distant station is indi-
the additional possible reroute paths available, block
cated and the fault isolation should continue following
diagrams will be prepared at each Technical Control
the procedures outlined in c above.
Facility for the area of interest, showing links between
connected stations and any appropriate extension
4-37. Circuit Status
that would permit a reroute to be made. These dia-
grams should be maintained in a conspicuous location.
The duty supervisor of the Technical Control Facility
c. C-reference data will be prepared to permit
must know at all times the status of circuits and equip-
ment removed from service because of failure or sub
proper designation of facilities required during coordi-
nation for the r&oration of service. For example,
standard performance. Positive action must be taken
commercial numbers will be used to identify circuits to
to ensure that:
commercial agencies. The cross-reference file will be
a. Notification is made when a circuit is determined
to be below acceptable quality standards and is to be
maintained in a position readily accessible to the Tech-
nical Controller on duty.
removed from service to restore it to an acceptable lev-
d. Within the DCS, Technical Controllers will, when
el. This notification should include the status of the
accomplishing control action& refer to circuits by
(1) The appropriate control offices have been noti-
CCSD, and will refer to trunks by the DCS trunk
nator. In all cases, it is essential that Technical Con-
(2) That service has been restored using a spare
trollers use equipment nomenclature and language
that is readily understood.
e. The primary responsibility for reroute action nor-
(3) That a spare channel is not available, and serv-
mally rests with the receiving Technical Control Facil-
ice to the user has been temporarily interrupted.
ity. The appropriate control office will be notified
(4) That a spare channel is not available, and serv-
when reroute action cannot be accomplished.
ice is restored by preemption of a lower priority user.
f. When the trouble on the original path of a rerout-
The prerempted circuit must be identified by CCSD.
ed circuit has been cleared and tested, the Technical
b. When user service must be interrupted, the Tech-
Control Facility initiating the reroute will take action
nical Controller coordinates with the local mainte-
to have the circuit returned to its original use and con-
nance activity for initiation of immediate repair ac-
figuration. Also, this TCF will take action to return
the path, used for the reroute to its original use and
c. Periodic progress reports on the restoration of
service will be provided to the duty supervisor so that
he can assure that the circuit is returned to service as