To truly have SWR, there needs to be a transmission line of a significant
part of a wavelength long. The line must be long enough for a standing wave
to develop.
Standing waves also exist on antennas.
Reflected power, the cause of standing waves, can exist whether there is a
transmission line of any length or not.
In the case of the antenna being connected directly to the plate of the
tube, it may resonate the tube plate with the plate capacitance and antenna
inductance.
There needs to be a resonant circuit in the plate to get maximum power
transfer.
Reflected power reaching the tube plate, not likely.
73
Gary K4FMX
> -----Original Message-----
> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]
> On Behalf Of Bill, W6WRT
> Sent: Wednesday, April 07, 2010 2:38 PM
> To: amps@contesting.com
> Subject: Re: [Amps] Hmmmm...Legal limit boiled the oil in the cantena
>
> ORIGINAL MESSAGE:
>
> On Wed, 7 Apr 2010 11:44:16 -0500, "Jeff Blaine AC0C"
> <keepwalking188@yahoo.com> wrote:
>
> >I agree with you for the real case. But to say by definition there
> can't be
> >swr - I think that would only be the case with infinitely small source
> and
> >loads and zero spacing between.
> >
> >So that for whatever conductor and distance there does exist between
> the
> >ultimate current sources and sinks "point zero", there would exhibit
> the
> >standing wave due to the mismatch. Even the anode, in a sense, has a
> >distributed conductor shape. Pretty smeared over the geometry involved
> -
> >but it's got to be there.
>
> REPLY:
>
> I have this pictured as the antenna bolted directly to the tube's
> anode. If that is not exactly the case, then SWR would exist.
>
> 73, Bill W6WRT
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