Topband: K9AY Loop Question

[James Wolf]

You can check the electrical operation of the relays on my page here in the FAQ.  http://wolfrfsystems.com/
Mark makes a good point.  A loop that is too close to the transmitting antenna can absorb enough energy to burn the termination resistors in the relay box at the antenna.  Decoupling the feedline is important at the antenna for max directivity.  

Jim - KR9U


-----Original Message-----
From: Topband [mailto:topband-bounces+jbwolf=comcast.net at contesting.com] On Behalf Of Mark - N5OT
Sent: Sunday, January 17, 2021 10:34 AM
To: TopBand List <topband at contesting.com>
Subject: Re: Topband: K9AY Loop Question

Hi Pete, I have a PILE of experience with K9AY loops, but I don't use them in the usual "one-support-two-loops-four-directions" 
configuration.  Mine are all individual loops on individual supports dedicated into arrays in various directions.

The first thing I would check is to make sure you have continuity through the torroid inductors/transformers.  I have had loops work only sort-of when it turns out one of the teeny wires opened up. So it ... 
"kind-of" worked.  Like I could hear some signals, but the loop just wasn't behaving like it was really supposed to.

Another thing you might check is to see that the termination resistor in the box is not somehow broken / open / shorted / something.  The other things you describe, shape of the loop, sloping ground, etc, seem to not matter in my experience.

Mark


On 1/14/2021 8:23 PM, N4ZR wrote:
> I'm in the process of putting up a K9AY loop, using the Array 
> Solutions/Wolf RF control boxes.  I had the antenna up last year but 
> it didn't seem to work very well, and I'm looking for suggestions.  A 
> couple of areas for which I've found no answers:
>
> How important is the geometry of the loops?  Illustrations I've seen 
> seem to imply that the lower legs should slope upward somewhat to the 
> corners, but without dimensions other than the total length of the loops.
>
> The ground around the antenna slopes slightly toward one side - should 
> I attempt to get the corners in the same plane, or the same distance 
> above ground?
>
> The relay box is mounted on the central fiberglass pole is 
> approximately 2 feet above ground.  Is this dimension important? The 
> relay box is grounded to a ground rod very close by.  Last year I 
> experimented with also laying a couple of radials on the ground under 
> the loops.  I read that suggested somewhere, but don't know if it's a 
> good or bad idea.
>
>

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