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Re: [IRCA] (Big Loop antennas)



Andy, is the same true for the ALA 100 loops? (ie the 2 turn loop).    In
Masset, my main ALA is quite a large circumference, about 20' base x 35'
height, and I have 2 loops.  Is there a need for separation of the 2
loops?  Mine are about 10 cm apart.   73,   Walt

On Sun, Apr 19, 2015 at 8:45 PM, Andrew Ikin <andrew.ikin@xxxxxxxxxxxxx>
wrote:

> Hello Chuck,
>
> W8JI's words as to the operation of terminated loops is disputed by K9AY.
> Gary Breed K9AY is quite correct when he states the antenna relies on the
> both interaction of the E and H Fields. The H field response of any loop is
> proportional to the antenna area.
>
> The termination resistance performs two functions; to balance the
> resultant EMFs induced in the antenna and reduce the phase difference of
> these EMFs. Hence, the antenna gain is dependant on the loop area.  BS
> Collins, who designed a Terminated loop array in the 70s and R Keen in the
> 1927 ed. of Wireless Direction Finding when describing a French design of
> the Terminated loop similar to the K9AY, both describe the antenna
> operation in a similar manner as Gary Breed.
>
> As a matter of interest one can double the loop area of the K9AY by using
> a two turn loop to increase the gain by approx. 5dB.
>
> 73
>
> Andrew Ikin
>
> -----Original Message----- From: Chuck Hutton
> Sent: Sunday, April 19, 2015 8:26 PM
>
> To: irca@xxxxxxxxxxxxxxxx
> Subject: Re: [IRCA] Station #500! (Big Loop antennas)
>
> For those interested, http://w8ji.com/k9ay_flag_pennant_ewe.htm has a
> paragraph describing the fact that the pickup for K9AY  and other
> "terminated loops" depends solely on the "vertical" aspect of the slanted
> wires and no pickup is contributed by the horizontal section on the bottom.
> Area of the antenna (as referenced in the article below) is therefore
> meaningless.
> Chuck
>
> From: charlesh3@xxxxxxx
> To: irca@xxxxxxxxxxxxxxxx
> Subject: RE: [IRCA] Station #500! (Big Loop antennas)
> Date: Sat, 18 Apr 2015 20:11:26 +0000
>
>
>
>
> Guy -
> The John Bryant article is only about KAZ antennas and doesn't touch the
> DKAZ version.I have some issues with the article - using a "surface area"
> concept to compare antennas whose gain is largely dependent only on the
> height of the vertical sections is not right.
> Chuck
>
>  From: dx@xxxxxxxxxxxxx
>> Date: Sat, 18 Apr 2015 13:03:33 -0700
>> To: irca@xxxxxxxxxxxxxxxx
>> Subject: Re: [IRCA] Station #500! (Big Loop antennas)
>>
>> Hi Nick,
>>
>> John's article on large DKAZ antennas is the one that came to mind for me
>> in this discussion of Super Loops. Although I believe a Super Loop is
>> rectangular, the big DKAZ may be of interest to Brian:
>>
>> http://www.dxing.info/equipment/kaz_bryant.dx
>>
>> John compared 112 Ft. X 28 Ft.and 40 Ft. X 10 Ft. DKAZ antennas for this
>> article.
>>
>> 73,
>>
>> Guy Atkins
>> Puyallup, WA
>>
>>
>>
>>
>>
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