Don
I’m afraid your information is not accurate, SAL is the same as a K9AY, the two
wires close to each other can be removed because they cancel each other. The
remain wires works like two vertical in phase, as the same in any flag, loaded
loop or pennant. The cardioid pattern is the same.
The is no implementation of two SAL in phase because it does not work, the
phasing system is too complex to phase two SAL.
If you know the people that actually tested the antenna, you know that the
claimed RDF was never achieved.
The RDF of the K9AY is the same of the SAL, the EZENEC does a horrible job with
loops close to the ground.
Saying that, both antennas are excellent receiver antennas if you don’t have
anything else.
73’s
JC
N4IS
Sent from Mail for Windows
From: Don Kirk
Sent: Thursday, January 6, 2022 7:19 PM
To: W0MU Mike Fatchett
Cc: topband
Subject: Re: Topband: K9AY Loop Questions
Hi Mike and gang,
It has been a long time since I looked at the SAL in which I modeled it
with the help of the designer of the SAL (KB7GF). The SAL is actually
different than the K9AY and other EWE types of RX antennas which have a
typical RDF value of around 7.8 because the SAL (Shared Apex Loop) antenna
actively uses two of its loops which are "in line" with each other for what
you might call the primary direction (direction in line with the loops),
and these two phased loops can provide an RDF value of around 9.2 depending
on the coupler locations. For the off axis directions (45 degrees to the
loops) I believe all 4 loops of the SAL are active (phased together) and
they provide a pattern more like what you would expect from the K9AY or
other EWEs with an RDF of approximately 7.8. Therefore in the 4 primary
directions of the SAL the SAL definitely has a better RDF than the K9AY or
other types of EWE receiving antennas.
When used "in line" the RDF of the SAL is around 9.2 as mentioned above
which is similar to what you would obtain using two phased verticals with
1/8 wavelength spacing.
Just FYI,
Don (wd8dsb)
On Wed, Jan 5, 2022 at 9:43 PM W0MU Mike Fatchett <w0mu@w0mu.com> wrote:
> The SAL is pretty much just an AY loop with a more functional
> controller? I have had moderate success with a pennant at V31 as well.
>
> W0MU
>
> On 1/5/2022 7:23 PM, john@kk9a.com wrote:
> > I tried an AY loop decades ago, without the Array Solutions adjustable
> > termination controller, and I do not remember it being that useful for
> RX.
> > The antenna is ground dependant so perhaps it works better for some than
> > others. Even a short Beverage may be a better choice. From my P40A
> station I
> > used a Pennant with decent results. It was inexpensive to build and not
> > ground dependant however it only covered one direction. The Array
> Solutions
> > Shared Apex Loop Array has great reviews and may be worth considering,
> Pete.
> >
> > John KK9A
> >
> >
> >
> > Pete Smith N4ZR wrote:
> >
> > I recently installed a K9AY loop (with the Array Solutions controller),
> > and have a couple of questions. Installation is pretty standard, with a
> > fiberglass pole at the center, ground rod at its base, and on the ground
> > radials under each direction of the loop.
> >
> > The antenna is directional, as demonstrated by tuning in broadcast
> > stations at the high end of the AM band and separating stations on the
> > same frequency so that I can hear one or the other. Atmospheric noise
> > is 1-2 S units more on my inverted L than on the K9AY antenna, but
> > signal strengths of stations in the favored direction of the loop seem
> > about the same or a bit lower than the inverted L. The Termination
> > adjustment is working, to judge by the switching transients, but seems
> > to make little or no difference.
> >
> > How do these results compare with others' experience? I didn't expect a
> > "magic bullet", but the K9AY loop seems a little bit underwhelming.
> >
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