Small rectangular morse code communications sender. The sender is mounted on a solid base. It is operated by finger touch and has a pointer that has a number of spring and screw adjustable points. The code sender is operated by the finger of the operator.“PATENTED No. 217455 VIBROPLEX THE VIBROPLEX COMPANY INC 833 BROADWAY NEW YORK”passchendaele barracks trust, morse code sender, communications

A telegraph or Morse key, sends a series of electrical signals down a telegraph line or via radio frequencies; the signals are interpreted as Morse code, a binary form of language constructed of 'dots and dashes', combinations of which correspond to letters of the alphabet. The motion of the key acts to complete an electrical circuit between the sender and receiver, producing a short pulse 'dot' or longer 'dash,' the space between the code indicates a broken current or wave.Device used to transmit telegraphic messages in Morse code through the manipulation of electric signals. The metal 'key' sits in a central bracket on which it moves up and down aided by a spring, controlled by an operator pushing the black Bakelite knob on the protruding end of the device. The motion presses the key onto a circular metal disc, completing the circuit and sending an electrical pulse to the receiver. The apparatus is secured to a wooden base with wires attached to the terminals; a cut out section of the base suggests wires may have entered through this area, attaching to a battery.Printed ink on base: "PMG"telegraph, telegraphist, morse code, mechanisation