A four-wire terminating set (4WTS) is a balanced transformer used to perform a conversion between four-wire and two-wire operation in telecommunication systems.
For example, a 4-wire circuit may, by means of a 4-wire terminating set, be connected to a 2-wire telephone set. Also, a pair of 4-wire terminating sets may be used to introduce an intermediate 4-wire circuit into a 2-wire circuit, in which loop repeaters may be situated to amplify signals in each direction without positive feedback and oscillation.
The 4WTS differs from a simple hybrid coil in being equipped to adjust its impedance to maximize return loss.
Four-wire terminating sets were largely supplanted by resistance hybrids in the late 20th century.
Famous quotes containing the words terminating and/or set:
“For, rightly, every man is a channel through which heaven floweth, and, whilst I fancied I was criticising him, I was censuring or rather terminating my own soul.”
—Ralph Waldo Emerson (1803–1882)
“Although knaves win in every political struggle, although society seems to be delivered over from the hands of one set of criminals into the hands of another set of criminals, as fast as the government is changed, and the march of civilization is a train of felonies, yet, general ends are somehow answered.”
—Ralph Waldo Emerson (1803–1882)