phantom circuit

American  

noun

Electricity.

1. a circuit derived from two suitably arranged pairs of wires, each pair being a circuit side circuit and also acting as one half of an additional derived circuit, the entire system providing the capabilities of three circuits while requiring wires for only two.

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Etymology

Origin of phantom circuit

First recorded in 1880–85

Example Sentences

The phantom circuit uses one of the physical pairs as a wire of its line.

From Cyclopedia of Telephony and Telegraphy, Vol. 2 A General Reference Work on Telephony, etc. etc. by McMeen, Samuel

As I was saying about this phantom circuit, it is used a good deal now.

From The Ear in the Wall by Reeve, Arthur B. (Arthur Benjamin)

A phantom circuit is formed most simply when both physical lines end in the same two offices.

From Cyclopedia of Telephony and Telegraphy, Vol. 2 A General Reference Work on Telephony, etc. etc. by McMeen, Samuel

One uncanny device, which would seem to be a mere inventor's fantasy if it had not already saved the telephone companies four million dollars or more, is known as the "phantom circuit."

From The History of the Telephone by Casson, Herbert Newton

When four wires are arranged to provide three metallic circuits for telephone purposes, two of the lines are physical circuits and one is a phantom circuit.

From Cyclopedia of Telephony and Telegraphy, Vol. 2 A General Reference Work on Telephony, etc. etc. by McMeen, Samuel