TONE DETECTIVE

E&MP128.013

Telegraph

June 1938

Ninety-six messages can now be sent simultaneously over a single pair of wires, Western Union announced, and demonstrated how this new development in communications science may be accomplished through the use of a Hammond electric organ. The organ generates musical tones, each of which can carry a separate message over the same wire. In the photo, Virginia Oman, organist, presses a key which supplies a channel over which a telegram is sent by the teleprinter operator. The Western Union "tone detective," by means of lights, shows which frequencies are being used. In regular service, the electric organ generator is concealed in a bank of other carrier channel equipment.

Original Caption by Science Service
^©Western Union