HOW CURRENTS TRAVEL

CD 2055052 E&MP5.019

Cables, Coaxial

about 1937

The high frequency signal currents travel in the surface layers of the inner conductor, and on the inner surface of the outer tube, which also acts as a shield on whose outer surface the unwanted interfering currents travel.

Like the shielding of a radio set, the outer tube keeps “static” out of the signal channel. 

Original Caption by Science Service
^©Bell Telephone