Topband: GAP Vertical Question

[Carl]

My own experience with 1/2 wave verticals is that they certainly do require 
a good ground.
Maybe a rod in a saltwater marsh is sufficient but not in many other cases.

Examples:

A Shakespere CB whip in my 66 Corvette which was advervtised for fiberglass 
cars. It couldnt be heard a mile away with 4W. I added "radials" from the 
base on the rear deck to the frame on all 4 corners and then it worked much 
better. This was back in the late 70's for several years.

A 80/40M 6 wire cage vertical, a full quarter wave on 80 and hanging from a 
tall pine tree branch at a prior QTH. With 60  65-70' radials it was 
competitive on 80 and on 40. With the radials removed it was a dud on 40. 
With another phased 1/4 wave on 80 it delivered the gain and F/B expected 
and 40 was improved with a pair of figure 8's but still not up to 
expectations. A 4el 40M KLM at 120' fixed that.

Carl
KM1H



----- Original Message ----- 
From: "Richard (Rick) Karlquist" <richard at karlquist.com>
To: "Donald Chester" <k4kyv at hotmail.com>
Cc: <topband at contesting.com>
Sent: Saturday, December 15, 2012 3:58 PM
Subject: Re: Topband: GAP Vertical Question


>
>
> On 12/15/2012 12:03 PM, Donald Chester wrote:
>>
>> From: charlie-cunningham at nc.rr.com
>>
>>   Could you support a vertical 1/2 wave for 160 with aballoon?
>> You could end -feed it at the base through a 1/4 wave of 450 ohm
>
>> But feeding a half wave vertical with the base near the  ground
> > still  results in substantial ground losses without a radial system.
>
>> Don k4kyv
>
> And this statement is based on what?  Publications, measurements,
> modeling?
>
> I have built a number of 1/2 wave verticals without radials and compared 
> them to 1/4 wave verticals with radials.  They are
> indistinguishable in performance and certainly do not exhibit
> substantial ground losses AFAIK.  The PAR electronics 1/2 wave
> end fed antenna seems to have a good reputation, unlike some
> GAP verticals.
>
> However, I don't recommend feeding it through 1/4 wave of 450
> ohm open wire line.  I just use an LC matching network.
>
> Rick N6RK
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