[Elecraft] OT: Grounding Question

[hawley, charles j jr]

I gave the reference. 4th edition of Terman, Electronic and Radio Engineering. Page 22. The chapter on skin effect. The rf current is pushed to the outside edge of any conductor because the rf current is distributed in such a way as to make most of it flow where it is encircled by the smallest number of flux lines. And that’s the outside edge of any conductor. The rf current in the center obviously would be encircled the most. Terman gives a very clear description if you can source his text. He states that it is not the amount of conductor surface, but rather the way in which the conductor material is arranged. And I do realize that this is a very misunderstood subject. I’m not saying that flat ribbon doesn’t have skin effect, but just where the rf flows. Much of the outside surface in the middle of the ribbon has a high resistance to rf. So if you are using a ribbon of wire, it would have to be much larger than a round wire to have any advantage.
I have the Radio Engineers Handbook also and it does not have the same chapter on skin effect.

Chuck KE9UW
c-hawley at illinois.edu

Sent from my iPad

> On Apr 25, 2018, at 1:34 PM, Josh <josh at voodoolab.com> wrote:
> 
> You're going to have to explain that to a whole lot of high current flat wound inductors & transformers. 
> 
> What are you referencing? The only Terman I have handy is Radio Engineer's Handbook. 
> 
> 73
> Josh W6XU
> 
> Sent from my mobile device
> 
>> On Apr 25, 2018, at 11:17 AM, hawley, charles j jr <c-hawley at illinois.edu> wrote:
>> 
>> RF does not flow on the entire surface of flat copper tape (Electronic and Radio Engineering by Frederick E. Terman 4th Edition, p 22). The RF current only flows on the outside edges of the strip, not on the middle outside surfaces. Think of looking at the end of a longitudinal slice out of a solid copper rod.
>> 
>> Chuck KE9UW
>> c-hawley at illinois.edu
>> 
>> Sent from my iPad
>> 
>>> On Apr 25, 2018, at 12:32 PM, Fred Jensen <k6dgw at foothill.net> wrote:
>>> 
>>> Sounds like you're following the rules.  You might consider flat copper tape instead of wire for bonding. Lightning is an RF event and currents will be confined to the outside surfaces of the conductors.  Consequently, the surface area rather than volume of the conductor is what matters most. The conductors on one of the original transmission lines from Hoover Dam to Los Angeles were hollow.
>>> 
>>> 
>