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Would the skin effect provide benefits or would capacitance/inductance cause problems?

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    $\begingroup$ What band is the J-pole for? Does the tinned braid include a metal foil layer? How would you get the tinned braid, would you pull the center conductor and the insulator out from coaxial cable, and then shove a narrow piece of PVC pipe inside? Please edit the question to give us more information. $\endgroup$
    – rclocher3
    Jun 30 at 17:18
  • $\begingroup$ OK, I'm just trying to decide if it's worth trying. I don't understand the reason for the downvote. $\endgroup$ Jul 1 at 13:43
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    $\begingroup$ I understand where you're coming from. This is a Q-and-A site and not a forum, so we like questions that could help other people who have similar questions in the future. Questions that are well-researched and well-written get upvotes. Yours probably got a downvote because it's a one-liner. By the way, a great place to get feedback on ideas that aren't fully-formed yet is the ham shack, our chat room, where there are a lot less rules. $\endgroup$
    – rclocher3
    Jul 1 at 16:07
  • $\begingroup$ Can we assume that what you're asking is, Is what you described better than a J-pole made from copper water pipe? Kindly edit your question to add these details. As it is, it's unclear what you're asking. $\endgroup$
    – Mike Waters
    Jul 2 at 22:14
  • $\begingroup$ It was downvoted because it needs more details. From ham.stackexchange.com/help/closed-questions: "Needs details or clarity - sometimes we need more information in order to help solve your problem. Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. Edit your post to be more specific about what you're looking for, and be sure to address any concerns that other users brought up in the comments." $\endgroup$
    – Mike Waters
    Jul 17 at 0:37
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For HF (e.g., 3MHz), the skin depth effect is <50 x 10^-6 m even for aluminum, and it is thiner for higher frequencies, so braid should be fine.

The bandwidth of the J-pole is affected by the diameter of the radiating element. The band is wider at higher frequencies, so to cover the 2m amateur band, you need about the diameter of rg58 shield. HF bands, being narrower, can stand a narrower diameter wire and still cover the band.

Having said that, I've made 20m and 10m j-poles, but I don't think a 160m j-pole is reasonable. :)

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    $\begingroup$ Haha! That DEFINITELY means we have to try it somehow! ;-) $\endgroup$ Jul 1 at 13:45
  • $\begingroup$ You mention aluminum. Does this apply to tin, which is what we're discussing here? $\endgroup$
    – Mike Waters
    Jul 17 at 0:32
  • $\begingroup$ Tin is irrelevant here. "Tinned" braid is probably nickel plated copper or something like that. (Although it could be tin.) The plating layer is less than the skin depth, so it's mostly copper. My mention of aluminum is because it's a good conductor with a thick skin depth. Most other good conductors will be thinner. $\endgroup$
    – user10489
    Jul 17 at 12:29
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RF will flow through the outermost layer of tin, in either tinned copper braid or tinned copper wire. Thus, very little current will actually flow through the highly conductive copper in the center.

The conductivity of copper is much better than tin. Tin is only 17% compared to copper at 100%. Will you notice a difference? The only way to tell is with two different J-poles and a proper test setup.

See this answer about tinned braid vs. solid copper. Note what might happen when the braid gets corroded and the individual wires get insulated from each other.

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    $\begingroup$ If that is the case, why bother EVER tinning copper braid? Why are all the ground cables tinned? $\endgroup$ Jul 16 at 23:13
  • $\begingroup$ @NonYaBidnezz To prevent corrosion. When copper corrodes, a poorly conductive oxide layer forms on each strand. Seems I read that that's bad when RF is involved. Perhaps there is another reason. In any case, I sprayed a clear coating on a shiny copper tank circuit strip in a homebrew 2m linear amp for that reason. (Silver plating would have worked.) However, this begs the (rhetorical) question, Will the coating break when flexed? $\endgroup$
    – Mike Waters
    Jul 17 at 0:21

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