But remember the antenna current will pass right thru that cone on the end
of the antenna. :>) :>) we have that from our local expert!
73
Gary K4FMX
_____
From: TexasRF@aol.com [mailto:TexasRF@aol.com]
Sent: Thursday, April 08, 2010 9:01 AM
To: garyschafer@comcast.net; amps@contesting.com
Subject: Re: [Amps] Hmmmm...Legal limit boiled the oil in the cantena
The corona ball at the tip of a mobile antenna is really important to proper
standing wave management. If it is completely symmetric, then
omni-directional radiation is assured. If it is asymmetrical, then increased
field strength can be obtained by proper orientation of the asymmetry. If it
is inverted cone shaped, the angle of radiation is lowered and concentrated.
Any CB field strength contester is aware of these little known phenomena.
73,
Gerald K5GW
In a message dated 4/7/2010 9:38:26 P.M. Central Daylight Time,
garyschafer@comcast.net writes:
Standing waves on the antenna are necessary for it to radiate. They are not
necessary to transfer power from the plate of the tube.
I hope that Bill Orr book arrives soon.
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 9:36 PM
> To: Amps reflector
> Subject: Re: [Amps] Hmmmm...Legal limit boiled the oil in the cantena
>
> ORIGINAL MESSAGE:
>
> On Wed, 7 Apr 2010 15:39:03 -0400, "Gary Schafer"
> <garyschafer@comcast.net> wrote:
>
> >Reflected power reaching the tube plate, not likely.
>
> REPLY:
>
> Not so. With the antenna connected directly to the plate (or through a
> DC blocking capacitor) I guarantee you there will be some reflected
> power returning back to the plate. Why? Even a perfectly resonant
> antenna does not radiate 100% of the power fed to it on each half
> cycle. Some power is reflected back from the end of the antenna to the
> feed point (plate of the tube) where it combines with the next half
> cycle. Antennas 101.
>
> The only exception would be an infinitely long antenna, and you are
> not likely to ever see one of those, especially mobile. :-)
>
> However, that reflected power does not contribute to SWR if there is
> literally no transmission line. It's just reflected power.
>
> 73, Bill W6WRT
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> Amps@contesting.com
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