I did not find that white paper very useful. Lightning protection planning normally assumes a direct attachment, and multiples thereof. I have rarely seen anyone go to such great lengths to explain effects of only a nearby strike, which happen on the scale of thousands of times more often, and with little if any effect, to a protected system. At the least it should not be labeled or implied that antenna and coaxial design would consider only their assumptions. The authors also failed to mention that proper grounding of the tower and proper shield grounding of coaxial cable would prevent the need for such unrealistically robust protector equipment as theirs reasoning suggsst are required, especially for only a nearby-strike, were that somehow the only consideration. Surge protectors and connected equipment can survive multiple direct attachments and thousands of insults from nearby strikes before failure when properly installed. When equipotential systems reach overload from the inductive effects of the high energy/fast rise times oif a direct attachment, current division via adequately sized conductors is the next defense. The surge protector equipment is the last defense, and there is scarcely a shadow of the massive potential of the original attachment or its current left by that time. Coaxial cable can only deliver about 5500v potential before it ruptures and shorts to ground. Maintaining equipotentiual along coaxial runs with frequent references to earth maintain a much lower potential than that, Thanks to our courteous authors for their donated paper, but there seems little if any practical design information in the work. Jack Painter
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