Correction to below: Change the word "frequency" to wavelength. It should read;
There is no "high frequency cutoff" but as the spacing of the center conductor and shield gets larger compared to WAVELENGTH a point is reached where the propagation mode of the cable changes and other modes come into play (where multiple propagation modes exist) and the multiple modes can interfere with each other causing partial cancellations. This causes additional losses. There is no "high frequency cutoff" but as the spacing of the center conductor and shield gets larger compared to frequency a point is reached where the propagation mode of the cable changes and other modes come into play (where multiple propagation modes exist) and the multiple modes can interfere with each other causing partial cancellations. This causes additional losses. 73 Gary K4FMX
