----- Original Message -----
From: "Al Williams" <alwilliams@olywa.net>
To: "WA8JXM" <wa8jxm@gmail.com>
Sent: Monday, May 23, 2011 9:43 AM
Subject: Re: [TowerTalk] Fw: Why radials improve radiation!
> No, it doesn't help me understand because it just rephrases what I tried
> to say in 2b of my question.
>
> In case of the dipole, if the two sides are of equal length then it would
> seem there is a place for the charge and discharge to be identical.
> However if the feedpoint is moved off-center the radiation according to
> EZNEC remains the same. Where is the current to charge/discharge the
> shorter side (to make up for the shorter wire) going?
>
> k7puc
>
>
> ----- Original Message -----
> From: "WA8JXM" <wa8jxm@gmail.com>
> To: "Al Williams" <alwilliams@olywa.net>
> Sent: Monday, May 23, 2011 9:26 AM
> Subject: Re: [TowerTalk] Fw: Why radials improve radiation!
>
>
> I don't know if this will help or not, but I'll try (at least according to
> my thinking):
>
> If you take a light bulb and run one wire to it from a battery, obviously
> the bulb will not light up. Why? because there is no place for current
> to go to.
>
> Likewise with an antenna. If you only have one connection (the center
> conductor), where will the current flow to? It needs either another
> element (such as the second side of a dipole), or a ground connection .
> Then you have two wires to accept your power.
>
> A good set of radials provides a good place for the rest of the circuit to
> send it's current.
>
> Does that help any?
>
> Ken WA8JXM
>
> On May 23, 2011, at 11:55 AM, Al Williams wrote:
>
>>
>> ----- Original Message -----
>> From: Al Williams
>> To: SteppIR@yahoogroups.com
>> Sent: Wednesday, May 18, 2011 8:23 AM
>> Subject: Why radials improve radiation!
>>
>>
>> Help, Help!
>> There have been many, many postings on how to set up the radials but
>> never a discussion on why or how radials actually effect the radials as
>> it seems to be "beyond the scope....".
>>
>> It is pretty easy to understand why from a circuit current loop viewpoint
>> i.e. the transceiver power output is divided between the radiation
>> resistance and the ground resistance (ignoring connector, coils, and wire
>> resistance).
>>
>> 1. However the radiation resistance is a make-believe or psuedo
>> resistance apparently derived from calculations of subtracting ground
>> system power (system loop current x ground resistance) from the
>> transceiver power output. Thus, since the loop current is known and the
>> remaining power is known, then the radiation resistance can be
>> calculated?
>>
>> But his seems analagous to lifting oneself up by pulling up on ones
>> bootsraps!
>>
>> 2a. For vertical antennas, it is said that there is no reflection
>> (radiation) from the ground system.
>> It isn't very clear why, horizontal or vertical polarization or ?
>> 2b. It is also that radiation is a result of the changing state of the
>> electrons in a material, caused by the changing current intensity. Thus
>> the material is acting like a capacitor (charging and discharging as the
>> current changes. For the material to charge/discharge there must be an
>> opposite charge/discharge somewhere?
>> 2c. Is this "somewhere" the ground or the radials? Do the radials allow
>> the antenna material to charge/discharge to greater amounts? Why and how?
>> 3. If 2c is true then "heating up the ground comments" hides what is
>> really happening?
>>
>> help help
>>
>> k7puc
>
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