[IRCA] The New Wellbrook K9AY Phased Array

["John H. Bryant" <bjohnorcas@xxxxxxxxxxxxxx>]

This is just a brief first impression of the new Wellbrook K9AY 
antenna trhat I am in the process of evaluating. I LOVE IT! Since we 
have returned to Oklahoma 10 days ago, I've managed to erect both the 
older first generation ALA100-based Phased Array and the 
all-new  K9AY version.  Both arrays incorporate twin Delta Loops with 
the two loops 40 meters apart.  I erected the two arrays parallel to 
each other, pointing due North-South for evaluation they are 
separated by about 300 feet, so there is little chance of interaction.

I've just spent two evenings running the two arrays, but I'm 
seriously in love. The ALA100 array has been my antenna of choice for 
the past three seasons and has been a wonder. The K9AY Array is even 
better, especially for domestic DXers.

Similarities in the two Arrrays:

Both have two 40 meter apart small delta antennas, the antennas are 
amplified at the head unit in each case

Both phase their two elements against each other to achieve very deep 
nulls that are instantly swappable fore and aft at the shack  (very 
important for domestic DXers and sometimes trans-oceanic ones.)

Both units can be easily expanded to operate two separate arrays so 
that one may cover all four cardinal directions, N, S, E, and West... 
or any two angles, since the two 2-antenna arrays are NOT 
interdependent. I'm actually running the two different arrays with 
one controller in the shack.

Both units were/are quite expensive (they are multi-unit Phased 
Arrays, after all)

Differences:

The K9AY array has a narrower front lobe (the ALA100 Array is, 
functionally, a full 180 degrees wide) This should help both in S/N 
ratio and in giving very different views of the band in each of four 
directions.

The K9AY array has deeper nulls.... so deep that they may not be 
fully measurable here in the winter, even at solar noon. EZNEC 
predicts about 5 to 10 dB deeper than the already deep 45 dB nulls of 
the ALA100 array.

The K9AY sports somewhat larger loop (base of each Delta is about 30 
feet, where the ALA100 unit base is about 20+ feet.) and the 
amplifier is technically even better and about 10 dB stronger.

The K9AY requires good grounding at each antenna element for best 
performance; the older ALA100 unit required no grounding.

Early Results:

I used my very accurate Winradio for these tests. HOWEVER, I paid no 
attention to the S-meter after peaking up the null before checking a 
frequency.

One test was at the lower part of the band from 540 through 730.  I 
maximized the null against the dominant southerly or northerly and 
then reversed the array.  I did this for each array, about 15 or 20 
seconds apart. There were 20 channels examined in that range (540 
through 730.)  On 15 of the channels, I marked something like "Much 
clearer on the K9AY" or "Much better on the K9AY" and, on virtually 
every channel, there was one station looking north and another 
looking south, at least on the K9AY.  One channel, 600, I marked 
"ALA100 seems better" and on one... 620 with Dallas and CKRM, the two 
antennas both performed equally well. The remaining three were inconclusive.

A couple of interesting notes: WWLS in Norman on 640 is one of my 
semi-local pests.  It is nearly impossible to completely null it with 
the ALA100 Array, especially at night.  The K9AY Array nailed it. WLS 
on 700 is off to the ENE and not nullable with this set-up, however, 
I had a strong Mexican beneath on the K9AY and nothing on the ALA100 
Array. I also snuck up to mid-bander 930, my favorite rock and roll 
station 50 years ago and a local pest that is VERY difficult to null 
with any antenna. I had CJCA to the North mixing with residual WKY on 
the ALA 100, but CJCA alone and stronger on the K9AY array. WONDERFUL!
.
On the upper part of the band, I just looked at 1600 to 1500 and the 
K9AY Array was superior here, too.  1600- had Cedar Rapids and 
Mexico, with the K9AY superior; 1590 was inconclusive as was 1580. 
1570 was my old buddy growing up, XERF. The K9AY was superior, but 
there was nothing identifiable in the null. 1560 was inconclusive; 
1550, 1540, 1530, 1520, 1510 and 1500 each showed the K9AY Array 
clearly superior! So three channels were inconclusive, due most 
likely to station locations and seven had the K9AY Array as the star.

1520 is worthy of special mention: that is the old rock and roll 
50,000 watts of KOMA, 50 miles due south of me, now a talker as KOCY, 
I think. It and 50,000 w - 740 KRMG in Tulsa, an equal distance to my 
east, is my worst nemesis.  I have never been able to null KOMA-1520 
with any antenna that I have ever usaed. KOMA is the only station 
that I had ever received here on 1520.... until two nights ago.  The 
K9AY Array put KOMA in the mud about 90% of the time and I heard 
WHOW, Clinton, Illinois-1520 along with at least one other station 
with almost no KOMA remaining.

I have yet to do any daytime test comparisons of the antennas or more 
formal evaluations, but I can already tell that the K9AY is a 
wonderful antenna.... the ALA100 was very good.... this is EXCELLENT.

In the coming weeks, I'll also be testing/comparing a two antenna 
Wellbrook Array based on two Conti Super Loops. That is not 
reversable from the shack, but probably out-performs even the K9AY 
Array as a single-direction antenna. Lastly, I'll be looking at the 
very modestly priced single Wellbrook FLG100 which appears to be 
superior for driving single flags, super loops, EWEs, KAZs, etc. The 
latter looks to be an EXCELLENT antenna for many at-home applications 
in suburban neighborhoods and even townhouses.  So, I've got an 
interesting winter ahead, here on the Southern Prairie.  Since these 
are all currently available Wellbrook antennas, I'll be able to post 
findings here in near real time, as well as finalize them in articles.

John Bryant
Stillwater, OK
WinRadio G313e + Ultralights
Wellbrook K9AY Phased Array







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