Nope, it can't get there that way. Nothing can get "thru" the chassis plate.
73
Gary K4FMX
> -----Original Message-----
> From: David Cutter [mailto:d.cutter@ntlworld.com]
> Sent: Friday, March 19, 2010 2:58 PM
> To: garyschafer@comcast.net; dezrat1242@yahoo.com; amps@contesting.com
> Subject: Re: [Amps] placement of RF choke bypass cap.
>
> Following logically from what you both say, my guess is that the load
> capacitors are fed with current via a nut and screw or the like. The
> current running from one surface of the chassis, via the screw head,
> along
> the surface of the thread to the nut and connection on the other side to
> the
> caps. Or have I got all wrong?
>
> David
> G3UNA
>
>
>
> > >>
> >> >
> >> >What do you think happens when you use a tube for an antenna
> element?
> >> >The whole element is charged. If you connect the feed line to only
> the
> >> front
> >> >side of the element there is still current on the back side of it.
> >> >How do you think the current gets around to the other side?
> >> >
> >> >But try to measure the current on the inside of the tube. You will
> find
> >> >none!
> >>
> >> REPLY:
> >>
> >> You raise an interesting question about current in a tube as opposed
> >> to a solid rod. In a sire or solid rod, the skin effect current is
> >> only present on the skin. In a tube however, I'm not so sure there is
> >> no current on the inner surface of the tube because that is also a
> >> skin. The issue is complicated because any skin current on the inside
> >> of the tube also "sees" the other side of the tube, unlike with a
> flat
> >> sheet where there is no other side. So that issue remains to be
> >> proven.
> >>
> >> Because a sheet has two "skins", and has no other side like a tube
> >> does, current flows on both "skins" of a sheet because it is repelled
> >> from the center. When one drains off current from one skin, the
> >> repulsion no longer exists and it is immediately replenished by
> >> current from he other side. Otherwise my load padder caps would not
> >> be connected to my load variable cap.
> >>
> >> Fascinating discussion.
> >>
> >> 73, Bill W6WRT
> >
> > Bill,
> >
> > My point is that there is no difference between the current on the
> outside
> > of a tube verses the current on your flat bar or a solid rod.
> >
> > Each skin acts independently of the other. One side of a sheet never
> knows
> > about the other side as far as current passing thru from one skin to
> the
> > other. This is very evident in a tube which has an inner and outer
> skin.
> >
> > Provided the material is several skin depths thick, there is never any
> > current on the inside.
> > Not because the current from one side acts against the current on the
> > opposite side but because the current on the "surface" sets up eddy
> > currents
> > just below the surface that oppose each other and cancel the deeper
> > currents. No current ever makes it to the center of the rod or plate
> or to
> > the inside surface of a tube.
> >
> > Current does not go "thru" the sheet or rod to get to the other side.
> It
> > flows around the edges.
> >
> > If current went thru the shield of coax then the coax would not work
> as it
> > does.
> > There is no way for current to enter the center part of a tube or rod
> or
> > flat sheet.
> >
> > 73
> > Gary K4FMX
> >
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