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

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

Thus, currents passing over a phantom circuit don't set up currents in the terminal apparatus of the side circuits.

From The Dream Doctor by Reeve, Arthur B. (Arthur Benjamin)

In phantom circuits formed merely by inserting repeating coils in physical circuits and doing nothing else, an exact balance of the sides of the phantom circuit is lacking.

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)

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