Just maybe a moot point but if I remember my transmission line math
correctly, the center conductor and the shield form the boundary conditions
for the wave equation so the RF energy in a coax line is actually in the
dielectric. When used at DC it just prevents you from getting shocked.
Hardy N7RT
----- Original Message -----
From: "Gary Schafer" <garyschafer@comcast.net>
To: <dezrat1242@yahoo.com>; <amps@contesting.com>
Sent: Tuesday, March 23, 2010 1:09 PM
Subject: Re: [Amps] placement of RF choke bypass cap.
> Bill,
> Perhaps you could explain to us why coax cable does not allow RF energy to
> move from the inside surface of the shield to the outside surface if not
> for
> skin effect?
> You would agree that the inside surface of a coax cable carries RF current
> would you not?
>
> You might want to google "RF skin effect". It might be educational.
>
> Also look at this article on G3SEK's web site regarding skin effect.
> http://www.ifwtech.co.uk/g3sek/misc/skin.htm
>
> 73
> Gary K4FMX
>
>
>> -----Original Message-----
>> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]
>> On Behalf Of Bill, W6WRT
>> Sent: Tuesday, March 23, 2010 10:05 AM
>> To: amps@contesting.com
>> Subject: Re: [Amps] placement of RF choke bypass cap.
>>
>> ORIGINAL MESSAGE:
>>
>> On Mon, 22 Mar 2010 13:03:07 -0400, "Gary Schafer"
>> <garyschafer@comcast.net> wrote:
>>
>> >Yes Larry, but the conclusion drawn by the one doing the experiment was
>> that
>> >the current "must go thru the disk when placed in the middle". No
>> account
>> >for capacitance was given.
>>
>> REPLY:
>>
>> Yes, it was given. In both experiments, the disk was placed with the
>> wire in the center and then repeated with the edge of the disk
>> connected to the wire. The capacitance was essentially the same in
>> both cases, as evidenced by essentially the same resonant frequency.
>> The conclusion they drew was the right one - the current flows
>> directly through the disk, NOT from the center, out to the edge and
>> back down the far side.
>>
>> Both of the experiments (the one with the antenna and the one with the
>> loop over a ground plane) allowed for capacitance and both came to
>> the same conclusion. What more do you want?
>>
>> 73, Bill W6WRT
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>
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