call drop
Date: circa 1884
Inventory Number: 8035b
Classification: Telephone Equipment
Dimensions:6.1 × 5.1 × 5.7 cm (2 3/8 × 2 × 2 1/4 in.)
Accessories: exchange jacknife switch (8035a)
DescriptionA telephone switchboard signal drop, roughly cubical in shape. The signal drop provided a visual means for a subscriber to signal the central switching station that the subscriber wished to make a call.
The device consists of a pair of electrical wire coils wound on cylinders and held by screws, parallel to one another, secured in a brass bracket. Above the coils is a plate with screw holes for use in securing the drop in place in a switchboard. Above the plate, a pair of metal columns supports a pair of plates, hinged together on one side. The top of the hinged pair has a metal half-sphere attached in the center. The movement of the hinged pair is restrained by a latch.
A length of electrical wire, covered with broken pieces of light-colored insulation, is wound around the drop.
In the switchboard the drop would be mounted in the switchboard so that the drop plate was vertical, and could be moved to an up or down position.
The device may have been collected by Robert G. Brown, an American engineer and inventor working in Paris on telephony in the late 19th C.