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When You Least Expect It, Expect It! Post #729

Antenna Feed Line Problems: Expect the unexpected
Accessed on 28 March 2016, 00:03 hrs, UTC.
Author:  Patrick Greenlee (NJ5G).
Please click title link to read the full article.


This intriguing article from Patrick Greenlee (NJ5G) entitled "When You Least Expect It, Expect it!" can apply to many radio amateurs who have unexplained and often frustrating SWR problems on their coaxial fed antennas.  In the past whenever I ran into the problem described by Patrick, I just "junked" the old coax, substituted a new coax cable feeder, checked SWR, and continued to enjoy "warming the ether."  Patrick has taken this troublesome issue one step further. He actually dissected his old coax to find the real cause of the unwieldy SWR readings he was getting.  He eventually discovered that the inner wire of the coax had shorted to the coax shield, thus giving erratic SWR readings.  He also found some coax "barrel" connectors and other attachments weren't made properly, leading to a multitude of issues.  Those responding to this well-written article offered some valuable tips on caring for coaxial cable:  coil  coax loosely, avoid tight turns and twists; buy quality coax and connectors; and replace old coax when SWR starts to rise.  Nicely done discussion on a feedline problem faced by many radio amateurs.

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Thanks for joining us today!  Aloha es 73 de Russ (KH6JRM).


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