The broadcasters also dont fall for the resonance bit either; very few
radiators plus radials have anything to do with an actual resonance.
All of this was explained back in the 30's.
Carl
KM1H
----- Original Message -----
From: "Milt -- N5IA" <n5ia@zia-connection.com>
To: "Eddy Swynar" <deswynar@xplornet.ca>; <herbs@vitelcom.net>
Cc: <topband@contesting.com>
Sent: Friday, February 10, 2012 12:11 PM
Subject: Re: Topband: Radials help
> HMMMMM!!!!!!!!
>
> If that is the case, WHY do the pro broadcasters install all 120 radials
> at
> full length; even bare wire buried a couple of inches underground?
>
> Inquiring minds want to know where this conversation is going.
>
> I understand that when you are doing radials, with a few they are part of
> the resonance factor for the vertical.
>
> However, after a dozen or so radials are installed the length does NOT
> necessarily determine resonance as the FIELD of "radials" becomes a
> composite Ground Plane.
>
> Bigger Ground Planes are Better!!!!!! Think salt water.
>
> So, IMHO, the 1/4 WL radius from the vertical is most likely at the break
> point for "return vs cost". And the more Ground Plane you can place in
> that
> 1/2 WL diameter circle, the more efficient your vertical will be.
>
> If I was installing insulated "radials" I would make them full 1/4 WL
> regardless of the VF. It just makes good engineering sense.
>
> I am still learning, so if I am incorrect in any of these items please
> enlighten me.
>
> Mis dos centavos.
>
> 73 de Milt, N5IA
>
>
> -----Original Message-----
> From: Eddy Swynar
> Sent: Friday, February 10, 2012 9:48 AM
> To: herbs@vitelcom.net
> Cc: topband@contesting.com
> Subject: Re: Topband: Radials help
>
>
> On 2012-02-10, at 11:34 AM, Herb Schoenbohm wrote:
>
>> One advantage of using insulate wire is that the velocity factor of the
>> wire
>> on ground or (ROG) allows for shorter lengths. This is important if you
>> have limited yard space.
>
>
>
> Hi Herb,
>
> Interesting point...!
>
> According to either the ARRL "ANTENNA HANDBOOK", or ON4UN's "LOW-BAND DX
> HANDBOOK", the velocity factor of insulated wire placed atop the ground is
> 50%...
>
> I take that to mean that a 1/8-wave PHYSICALLY long wire radial has the
> ELECTRICAL equivalency of a wire radial that is 1/4-wave long...
>
> Maybe THAT'S the reason why I employ a total of 24 insulated radial wires,
> 65' long (each) beneath my "L" elements...it may not be an "exact
> science",
> but hope springs eternal...! (Besides, have you seen the price of copper
> wire lately...?!). : >)
>
> ~73~ de Eddy VE3CUI - VE3XZ
> _______________________________________________
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