As a result of considerable investigation and study of the methods,
equipment, and manpower which might most effectively be used for cable
laying, it was decided that complete lengths of cable required for each
run would be preassembled and tested on shore. Assembly involved the
insertion of splice cases containing 88 mh loading coils at 6000 foot
intervals in the cable length. The splice cases were rectangular, ap-

proximately 6 inches by 28 inches and weighed about 95 pounds.

Based

upon the experience reported in connection with cable laying operations for the Sandstone Project, it was planned to lay the cable fram
a towed barge upon which the cable was arranged in a figure-8 pattern,
each successive coil of the figure-8 progressing by at least one diameter of the cable towards the stern of the barge. This type of

arrangement avoided the cable torque encountered during the Sandstone

activities. In addition, the tendency of the cable to stack up at the
crossover of the figure-8 was considered beneficial because each successive coil could slide off freely in the direction of the fair lead
to be provided on the cable laying barge.
The employment of a towed barge eliminated the propeller hazard
previously encountered in the use of a landing craft and, thus, also
made it possible to avoid the unnecessary flexing of the cable by lay-

ing it over the side of the ship.

The cable laying barge was equipped,

in addition to a set of fair leads for guiding the cable toward the
stern, with a mamally operated cable brake and a stern guide plate to

lead the cable off the barge at an angle between 30° and 60° from the

horizontal, Auxiliary equipment included winches, anchors, block and
tackle, splicing gear, and the like, The cable brake was designed to
be removable from the line of movement of the cable in order to permit
the passage of the splice cases. In order to avoid any possibility of

loss of efficiency, it was specified that communication cables were not
to cross other submarine cables laid in the lagoon. It was, therefore,
specified in addition that all existing cables should be accurately

located and that the paths of newly laid cables should be fixed by

successive sextant angle shots taken from the barge, during operations,
to fixed points on shore,
Cable landings designed called for a trench
line depreciation in which the cables were closely grouped amd covered
with a compacted mixture of Bitumul, sand, cement, and water. Upon the
completion of the laying of each cable, a series of tests was conducted
to supplement the information obtained from the prelaying tests. These
tests involved the contimity loop resistance of each pair in the cable
and the unbalanced resistance between wires of each pair; the insulation resistance of each wire to every other wire in the cable; transmission loss at 1000 cycles and 2500 cycles for loaded pairs and 1000
cycles and 5000 cycles for nonloaded pairs; and the measurement of near
end and far end crosstalk. The results of these tests are presented as
exhibits at the end of this volume together with other test records of
main telephone trunking cables and representative branch cables.
The successful operation of the mamal telephone system with submarine cable trunking justified the original recommendations. I+ was
possible, in addition, to allocate certain pairs of the submarine telephone trunking cable for control and signal use by at least one scientific group to serve their increased requirements. Trunking facilities

functioned satisfactorily throughout the operation.

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