Ken,
I am thinking along the lines as Gregg. Try disconnecting the feedline
at the antenna and compare noise levels.
Do you have a choke on both ends of the feedline ?
Bob
K6UJ
On 4/26/16 6:00 PM, Ken K6MR wrote:
Good idea Gregg. I suspect there may be some common mode problems.
I did discover one problem thanks to questions from K6UJ: the resistors on the
loops need to be non-inductive and the ones I installed are not. Dumb error on
my part. When I lower the antenna to change the resistors I will be able to get
to the feedline connector. So that is something I can do easily. I also have
more ferrites so I may add some additional feedline chokes since I have to cut
the feedline loose from the mast anyway.
Thanks,
Ken K6MR
From: Gregg W6IZT<mailto:gregg.w6izt1@gmail.com>
Sent: Tuesday, April 26, 2016 17:34
To: topband@contesting.com<mailto:topband@contesting.com>
Subject: Re: Topband: Waller Flag construction and performance
Ken:
No directivity and noisier than the TX vertical. Perhaps you should look at
these as two separate observations. Try disconnecting the feedline at the
antenna. What is the noise level with the antenna disconnected and the pre-amp
gain adjusted for 35-40 dB?
73
Gregg
W6IZT
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Ken K6MR
Sent: Saturday, April 23, 2016 6:11 PM
To: Clive GM3POI <gm3poi2@btinternet.com>; topband@contesting.com
Subject: Re: Topband: Waller Flag construction and performance
No it does not and that’s a good point. I’m pretty sure the vertical 800 feet away is
not much of an issue, but the tower within 150’ could be a problem. The model is going to be
difficult because there are four yagis on the tower. Good project for a rainy day.
I have one other tower about 350’ away that also has multiple yagis but
hopefully that also is far enough.
The other option is to move it to one of the other towers and change to horizontal
polarization and up higher. N4IS seems to prefer that orientation. At the moment the
performance is so poor that I’m thinking I did something wrong in the assembly.
Ken K6MR
From: Clive GM3POI<mailto:gm3poi2@btinternet.com>
Sent: Saturday, April 23, 2016 15:03
To: 'Ken K6MR'<mailto:k6mr@outlook.com>
Subject: RE: Topband: Waller Flag construction and performance
on Locked="
Ken, When you say the EZnec model looks great does that include the other
towers.? If not include them and reassess.
73 Clive GM3POI
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Ken K6MR
Sent: 23 April 2016 18:38
To: Bob K6UJ; topband@contesting.com
Subject: Topband: Waller Flag construction and performance
Let’s start here and see how it goes. If someone complains we’ll take it off
line. Nothing like a public discussion to bring out the best ideas. I changed the subject
line so the discussion will make sense.
The 160 transmit vertical is about 800’ away. There is an 80’ tower with various
higher band yagis on it about 150’ away.
My loop size is 12’ high, 10’ wide. 4’ between loops. Vertical loops. The boom is 50’
high. The tower is near the house, but single story house so the boom is 35’ above the roof.
The EZNec model looks great (of course). The gain models a bit low, but the RDF
and gain test are in the right ranges. Right now the big problem is no
directivity and it is actually noisier than the vertical. I have the adjustable
gain pre-amp from DXE (KD9SV design) in the shack.
So that’s the background. Common mode problems would indeed be my first
suspect. Interested in how you handled it.
Ken K6MR
From: Bob K6UJ<mailto:k6uj@pacbell.net>
Sent: Saturday, April 23, 2016 11:00
To: topband@contesting.com<mailto:topband@contesting.com>
Subject: Re: Topband: The band sans noise
rue" Name="index 1"/> <w
Hi Ken,
Be glad to. It took me a while to get mine working, found some basic things I
needed to do and it now works very well.
First a question. How far is your flag from the house and also an antenna
tower or other metal structures ? I had to detune my tower it is only 40 feet
away from the Flag. After this we can go over the construction of the Flag and
its feed system issues like eliminating common mode interference. Maybe it
would be best to discuss this directly rather than the reflector ?
I can be long winded. hihi
Bob
K6UJ
On 4/23/16 10:42 AM, Ken K6MR wrote:
Interesting comments about the WF. I recently built one and so far it has been
a complete failure.
Care to share the details?
Ken K6MR
From: Bob K6UJ<mailto:k6uj@pacbell.net>
Sent: Saturday, April 23, 2016 10:30
To: topband@contesting.com<mailto:topband@contesting.com>
Subject: Re: Topband: The band sans noise
Bill,
Sounds great ! hihihi A lot cheaper than a Pixel too !
Until now I have kept my comments to myself about the Pixel.
I had a Pixel for a short time and sold it.
At the time I had electrical hash from one direction due to loose
hardware on a power pole.
It took forever for our utility company to fix it. I have a Waller
Flag for receive on 160 and it was very effective at nulling out the
power pole noise. I read all the rave reviews on the Pixel and
thought it would outperform the Flag for nulling out the noise and was
also curious how it compared to the flag on picking up 160 DX signals.
The Pixel did provide a nice null from the power pole noise but not
nearly as deep of a null as the Waller Flag. On discriminating
160 DX from the band noise level
it was very poor indeed. The Waller Flag way out performed the Pixel.
I could hear DX stations with the
flag and could not hear them at all on the pixel when receiving
stations close to the noise level.
The Pixel would be suited for someone in an apartment or with a small
lot and doesn't have the room for a larger receiving antenna like the
Waller Flag. It is a compromise receiving antenna but we have to work
with what we have as far as room for antennas.
73,
Bob
K6UJ
On 4/23/16 9:45 AM, william radice wrote:
:::: I have an antenna of very similar design and performance. It is
an all aluminum lawn chair on a pole.
BILL
On 4/22/2016 1:42 PM, Rob Atkinson wrote:
Throw bricks all you want to the end of time but you'll never change
the fact that we tested that antenna and saw its performance first
hand; The preamp was designed by Jack Smith at CliftonLabs..I'm sure
he'll enjoy reading your comments and get a good laugh.
73
Rob
K5UJ
On Fri, Apr 22, 2016 at 11:26 AM, JC <n4is@comcast.net> wrote:
SORRY am not getting into this PR.. PIXEL loop is a low RDF and LOW
performance receiving antenna, it is really snake oil.
I'm out of this discussion.
Regards
JC
In tests, the Pixel magnetic loop provided at least 20 dB null off
the sides. From my experience, that is much better "filtering" than what
would be had with a horizontal loop. Of course it isn't all in the
antenna itself--a great deal of the success comes from the special
preamp designed for use with the antenna.
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