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TM 11-5895-1012-10
equipment is available, spare circuits, which corre-
channels, rerouting of circuits, or cause interruption of
spond to the DCS options in use at the station, may be
service must generally be reported to higher headquar-
established to permit rapid restoration of circuits by
ters. The specific reporting procedures to be followed
in-station patching.
are contained in the current station SOP.
a Equipment Substitution. No operations reports
4-18. Patching Precautions
are required for the substitution of equipment during
a. Temporary Measure. The use of patchcords to set
routine maintenance operations. A Failure Report
up or rearrange circuits is intended as a strictly tem-
must be completed, however, if an equipment failure
porary measure. Service restoration patches should be
has occurred.
taken down as soon as the fault condition has been
b. HF Patching. Except as authorized in the current
cleared. In some cases, circuit orders may be issued
SOP, group patches may not be performed in the
which specify that patchcords be used to set up or rear-
multiplex ares without prior coordination with, and
range a circuit to fill an emergency or temporary re-
approval of, the DCA and ACC. Notice must be fur-
quirement. Such orders may specify, for instance, that
nished to the DCA and ACC following completion of
circuits be established without delay by patching, and
the HF patching operation.
c. Channel Substitution. The DCA sad ACC must be
later by cross-connected at the frame to make a per-
informed when a circuit is transferred to a spare chan-
manent configuration. The patch is to be taken down
as soon as the normal circuit is arranged. The opera-
nel, or to a channel of lower priority circuit. The notice
tional objective is to keep the jackfields as free of
should specify the time, circuit number, channel desig-
patchcords as possible. A multiplicity of patches in a
nator, reason, and expected duration of the rearrange-
ment. This report is normally submitted after-the-fact,
jackfield frequently results in confusion as to the pur-
since the Technical Controller must take immediate
pose and authority of the patches, and whether they
action when patching is required to restore service.
are still required. To preclude such confusion, identifi-
When it is necessary to preempt a lower priority cir-
cation tags should be attached to any pat&cord setup
cuit to obtain a substitution channel, the using agency
which is to be left in place at the end of a Technical
must also be informed. When the circuit is restored,
Controllers duty shift. The identification tag should
the using agency and higher headquarters must be
contain the following minimum information: circuit
number, terminal locations, using agency, mode of
operation, authority, and time to be taken down.
4-20. Patching Operations Condu
b. Patching Technique and Sequence. When patch-
the VF Patching Facilities
ing operational circuits, it is essential that interrup-
a. General. The jackfields associated with the VF
tion, or service outage resulting from the actual patch-
patching facilities are used to gain access to signals in
ing procedure, be kept to an absolute minimum dura-
voice-frequency (300 to 3400 Hz) circuits for monitor-
tion. In most patching operations, it is possible to limit
ing purposes, and to perform circuit rerouting, test
the effect on a VP circuit to a momentary click, and on
measurements, level adjustments, and restoration of
a TTY circuit to a few garbled characters. This mini-
service by equipment substitution. Representative
mum effect can be realized, however, only when the
patching operations are given in b, c, and d below. The
Technical Controller selects and follows the correct se-
patch panels and jacks used are discussed in Chapter 2.
quence in inserting the plugs in the jacks. The order in
The patching operations are shown in figures 4-1
which this is done is important. Each of the many pos-
through 4-3.
sible patching operations must be considered individu-
ally to determine the optimum order of events in the
The patching operations described below do
patching procedure. Experienced Technical Con-
not take into consideration the extension of
trollers always take a moment to think out the whole
E&M signalling leads through a patch panel.
patching procedure before plugging into the jacksets.
Where there is a signalling lead extension,
In general, the spare or alternate signal path should
use additional patch cords to transfer over all
be set up first. The plugs should then be loosely set in
portions of the circuit.
the proper NORMAL-THROUGH jacksets, located in
the signal path of the circuit to be transferred. Finally,
b. Transfer of a Circuit to a Spare Multiplex
in a coordinated procedure, the plugs should be simul-
Channel (fig. 4-1). The situation requires, for test or
taneously pushed all the way into the NORMAL
maintenance purposes, that the user assigned to
THROUGH jacksets at two locations that constitute
channel 5, be transferred to channel 2. This patch is
the end of the substitution path.
made at the equal level patch panel (fig. 2-15) and the
procedure is the same for Station A and Station B.
4-19. Reporting Patching Operations
(1) Place two patch cord plugs loosely into channel
Patching operations which result in reconfiguration of
2 REC LINE and TRANS LINE jacks.

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