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Re: [Amps] placement of RF choke bypass cap.

To: <dezrat1242@yahoo.com>, <amps@contesting.com>
Subject: Re: [Amps] placement of RF choke bypass cap.
From: "Gary Schafer" <garyschafer@comcast.net>
Reply-to: garyschafer@comcast.net
Date: Wed, 24 Mar 2010 15:45:02 -0400
List-post: <amps@contesting.com">mailto:amps@contesting.com>
>>why do you think that
>>there is not skin effect in a flat plate conducting RF current?

> On Behalf Of Bill, W6WRT 
> REPLY:
> 
> I never said there wasn't, in fact I agreed there is. Go back are read
> my previous posts in this thread.

Bill,
How many times do you want me to quote you saying that "skin effect does not
keep RF from flowing thru a plate"? it has been in almost every one of your
posts. That is what started this whole thread and continues it.
---------------------------------------------
This is one quote:
"If what you say was true, all our radios and amps would not work.
There are dozens if not hundreds of places where RF passes through sheet
metal from one side to the other, such as through the shield side of a coax
connector."
---------------------------------------------
This is another quote:
"Having said that however, the skin effect does not stop current from
flowing through the chassis. A good thing too, or stuff wouldn't work.
73, Bill W6WRT"
---------------------------------------------

Then you get off on this tangent with the plates inserted in antenna legs to
try and bolster your position. 
That is a whole other kettle of worms and a lot more going on there, as I
said before, than just a matter of skin effect or no skin effect. There are
currents being coupled from end to end of the antenna and around the plates
that are not readily apparent. 
That model can not be used to prove or disprove skin effect.

If you want an experiment that does show how skin effect isolates one side
of a plate from the other re-read W8JI's experiment. It is the closest thing
to the RF current flowing on an amp chassis as you will get. Signal injected
across two points on one side. It can be measured on that side with a probe
and can not be measured on the other side of the sheet. 
http://www.w8ji.com/skindepth.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 10:37 PM
> To: amps@contesting.com
> Subject: Re: [Amps] placement of RF choke bypass cap.
> 
> ORIGINAL MESSAGE:
> 
> On Tue, 23 Mar 2010 19:54:46 -0400, "Gary Schafer"
> <garyschafer@comcast.net> wrote:
> 
> >
> >So if there is skin effect in play inside of the coax why do you think
> that
> >there is not in a flat plate conducting RF current?
> 
> REPLY:
> 
> I never said there wasn't, in fact I agreed there is. Go back are read
> my previous posts in this thread.
> 
> What I did say was that the presence of skin effect did not prevent RF
> from flowing through a flat plate at a 90 degree angle, as the two
> recent experiments proved.
> 
> Electrons respond to both electric and magnetic fields. Skin effect is
> primarily a magnetic effect caused by eddy currents in the body of the
> conductor which repel electrons away from the center and toward the
> skin, but that repulsion can be overcome by a positive charge which
> pulls the electrons in a different direction. The skin effect current
> and the "wire through the plate" current are at 90 degrees to each
> other. The effect of on the other appears to be very small.
> 
> As the two gentlemen showed, there is no reason both effects can not
> be present at the same time.
> 
> 73, Bill W6WRT
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