History
The need for loading coils was discovered by Oliver Heaviside in studying the disappointing slow speed of the Transatlantic telegraph cable. He concluded additional inductance was required to prevent amplitude and time delay distortion of the transmitted signal. The mathematical condition for distortionless transmission is known as the Heaviside condition. Previous telegraph lines were overland or shorter, hence had less delay and the need for extra inductance was not so great. Submarine communications cables are particularly subject to the problem, but early 20th century ones using balanced pairs were often continuously loaded by iron tape rather than discretely by load coils.
Read more about this topic: Loading Coil
Famous quotes containing the word history:
“It is remarkable how closely the history of the apple tree is connected with that of man.”
—Henry David Thoreau (1817–1862)
“It’s a very delicate surgical operation—to cut out the heart without killing the patient. The history of our country, however, is a very tough old patient, and we’ll do the best we can.”
—Dudley Nichols, U.S. screenwriter. Jean Renoir. Sorel (Philip Merivale)
“History ... is, indeed, little more than the register of the crimes, follies, and misfortunes of mankind.
But what experience and history teach is this—that peoples and governments have never learned anything from history, or acted on principles deduced from it.”
—Georg Wilhelm Friedrich Hegel (1770–1831)