Here is my answer to your question about a comparison between a K9AY
four square and that of a full size four square on 160 meters.
Assume a full size 160 meter 4 square 1/4 wave spacing and a K9AY 4
square using 40 meter spacing, and both use quadrature phasing, and make
the assumption that each is operating close to optimum, the full size
four square will be a little better overall.
In the azimuth direction front-to-back is close for both, with the full
size 4SQ slightly better (that's average rear response, not minimum
response value). The forward lobe beamwidth is also very close, for the
K9AY about 96 degrees at 24 degrees elevation, and for the full size 4SQ
about 98.6 degrees at 20 degrees elevation.
In the elevation direction, the K9AY 4SQ has a beamwidth of 52 degrees
with a take-off angle of 26 degrees. Straight up the response is down 11
dB. The full size 4SQ has a beamwidth of 38.6 degrees with a take-off
angle of 20 degrees, and a null overhead.
Overall the full size 4 square will have a better signal-to-noise ratio
because of less high angle response due to the narrower forward lobe in
the elevation direction. Less high angle response in these antennas is
very important because thunderstorm QRN originating in the US will be
arriving at high angles and these sources will have large signal amplitudes.
The performance of both of these antennas will improve significantly if
optimized phasing is used.
Jerry, K4SAV
Bob Maser wrote:
>Of course the $64 question is: How much is the 4 Square K9AY? I wonder how
>much better is it than a full size 4 square.
>
>Bob W6TR
>----- Original Message -----
>From: "Joe Szeliga" <j.sz@transam.home.pl>
>To: "Jay Terleski" <jayt@arraysolutions.com>
>Cc: <towertalk@contesting.com>; "Gary" <gary@aytechnologies.com>
>Sent: Tuesday, December 19, 2006 5:48 AM
>Subject: Re: [TowerTalk] K9AY Loop
>
>
>
>
>>Dear Gents,
>>K9AY is great antenna. But big improvement in reception
>>is obtainable to form it to 4 square.
>>20 set's was build and 13 are in use with big success
>>(7 sets are sill available on my stock.)
>>K9AY & 4SQUARE ...??? Yes !
>>The magic boxes including Phasing Networks and Switching Directions of 4
>>Square K9AY Array don't make magic its work perfectly,
>>remotely controlled from shack via feed line
>>details here:
>>http://www.sp3key.com/klub/k9ay_pro/index_en.html
>>
>>Jay was nice to see you in Friedrichshaffen
>>cu soon in USA.
>>I'm happy that all with the Hamation bandpass filter unit
>>has his happy finale.
>>
>>best regards
>>Vy 73's
>>Joe Wojciech Szeliga, SP9P
>>
>>
>>
>>>Gents,
>>>The K9AY new loop is still Gary's great antenna design.
>>>
>>>It does require a ground but not 1/4 WL radials only some that are say
>>>16 feet long if you need them at all with the required ground rod.
>>>In the latest incarnation of the K9AY loop that were doing not only do
>>>we have a ground rod provision but include a nice milled radial ring
>>>under the fiberlass poles in the mast kit to allow radials to be easily
>>>attached to beef up the ground if needed, like coral reefs, rocky soils,
>>>top of your garage roof, etc.
>>>
>>>It will perform as the spec. says, and it will allow DXpeditions and
>>>postage stamp backyards to play with the big boys with beverages if
>>>installed right.
>>>
>>>The loop is a great antenna idea and is like a short two element
>>>veritical with 25-30+ db of F/B. So the noise is reduced and you can
>>>hear.
>>>It needs to be set up with consideration to the TX antenna like any RX
>>>array. Furthar away is better. But it still works and doesn't cost an
>>>arm and a leg!
>>>
>>>Next step is to take this very directive element (array) and make it
>>>into a larger directive array. Which should open some eyes since were
>>>starting with a directional antenna and not a whip. Gary has agreed to
>>>help with this design. It doesn't suffer from being an open FET voltage
>>>sampler antenna, it is already a terminated matched device so it matches
>>>to your feedline without problems and doesn't need special inductors/
>>>swamping resistors inside. Another advantage to those of you who know
>>>about preamps and band pass pre-filters.
>>>It also is not an open FET or transistor input, it has the properly
>>>matched band pass filter ahead of the gain stage, so IMD is very small.
>>>We test it for this.
>>>
>>>Don't believe the negativity of Gary's design that you read on TTalk.
>>>Please. This is a well designed arrray, Gary knows his stuff. Many DX
>>>peditions have used it to hear your signals.
>>>And I have compared it to my 6 direction 600 ft beverage arrays. It's
>>>almost as good. Just like any antenna, if it is poorly erected it will
>>>perform poorly.
>>>
>>>Merry Christmas to all.
>>>
>>>Jay, WX0B
>>>
>>>
>>>
>>>>
>>>>
>>_______________________________________________
>>
>>
>>
>>_______________________________________________
>>TowerTalk mailing list
>>TowerTalk@contesting.com
>>http://lists.contesting.com/mailman/listinfo/towertalk
>>
>>
>
>_______________________________________________
>
>
>
>_______________________________________________
>TowerTalk mailing list
>TowerTalk@contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|