An Experimental Clogston 2 Transmission Line

Clogston 1 has discovered that it is possible to reduce skin effect losses in transmission lines by properly laminating the conductors and adjusting the velocity of transmission of the waves. During a period in late 1951 and early 1952, a transmission line completely filled with laminated material was constructed and its loss was measured in the frequency range from 1 to 25 mc. This structure is referred to as the Clogston 2 stack to distinguish it from the Clogston 1 described by Black, Mallinckrodt and Morgan. 2 The measured loss was compared with the loss computed by Morgan for a uniform line and was found to match at low frequencies, but to rise to a value of twice the computed loss at 10 mc. The ratio of measured loss to computed loss was nearly 2 to 1 over the 517 518 THE BELL SYSTEM TECHNICAL JOURNAL, MARCH 1 9 5 9 remainder of the measured frequency range. The explanation of this difference awaited the work of Raisbeck 3 on the effect of lack of uniformity in a laminated line. The measured loss was then compared with the loss computed by Raisbeck and was found to match reasonably well in the frequency range where the computation is expected to be valid. A description is given of the construction of the line and the technique used for measuring, with some emphasis on the way this line departs from the ideal. I I . CONSTRUCTION O F T H E L I N E