Topband: 160 4 square

Mon Aug 28 07:47:15 EDT 2017

Hi Lee

Good question, The HWF has a deep null on vertical signals, propagated noise
like ground wave can be attenuated over 80 db. The tower on the center of
the WF does have little effect adding noise into the HF. Actually the WF
load the tower and lower the resonance as result.
I detained my tower in 2006 when I started to use my vertical WF, called Big
Waller Flag by Doug. I never noticed any interaction with the HWF from 2009
to 2015. I used a local BC signal as reference to detune the tower and take
polar plot diagram. 
The noise during the day on my WF is always zero. It means below the
sensitivity of my receiver system  near 1 db NF. Two year ago I had a power
line noise very close to my home, 500ft or less, I posted a video about the
contest under that kind of QRM.  With that QRM I noticed some noise during
the day. Pete N8PR come to help me to check it and we adjust the tuning
capacitor and I was able to remove 6 more db of noise fining de-tuning the
tower, Just a reference I was using 35 pf and after I removed it, 0pf) I got
-6bd of noise reduction, Whiteout the strong local QRM I was not able to
notice it before. 

Detuning the tower can bring -20 to -30 db  noise re-radiation, but
re-radiation is not zero, Some HF antennas sharing the same mast with a WF
can interact with the WF on the same frequency, balance is the name of the
game. Unbalanced loops cannot cancel 100% of the noise, but the interaction
in most case are not severe with HF beam and good performance is expected in
most installations. However Inverted V and re-radiate almost 2 s units of
noise and must be detuned open fiscally the wires near the coaxial feed line
or balun.

The advantage of a horizontal antenna besides noise is the horizontal
propagation on low bands, Refraction is more intense on 160m than 40m, it
means the signal bent more on the topband, as a result the path for
horizontal signal is not the same as vertical polarized signals, It is
common to see signals from deep Asia, Nodir as example EY8MM signal direct
is 10 degree here but several times I can hear only between 60 and 90 degree
when there is no copy from 10 degree. 

Long path or really SSW SSE propagation is another propagation mechanist
that brings the signal horizontal most of the time. On 80m I can hear south
Asia HS0 XU 9M2 almost every day during the DX season, 160 is very common
SSE SSW as well. I can compare the difference with my Vertical WF and also
with other folks in Florida , like Doug NX4D that's uses only vertical pol,
during 2010 when the SSE SSW was very strong I could hear XU7ACY 80% is the
time and Doug only 5 % of the time.

Vertical signals are always strong, as well the noise. Sometimes there are
not horizontal signals as well. However I manage to work almost  DX
expeditions like VK0,E31,H40,FT4, 3D0A, ET, VP8's,EP FT5ZM, 9M0 , I missed
only H44 due QRN. I was not able to work YB, BY  JT XX9 XV XW and few others
SSE/SSW path on 160m, 80m is so easy SSE SSW that signals can be hear 2
hours after sunrise, and sometime 2 hours before sunset.

Regards
JC
N4IS

-----Original Message-----
From: Lee STRAHAN [mailto:k7tjr at msn.com] 
Sent: Monday, August 28, 2017 2:03 AM
To: JC <n4is at comcast.net>; 'GaryK9GS' <garyk9gs at wi.rr.com>; 'Greg'
<n4cc at windstream.net>; 'topband' <topband at contesting.com>
Subject: RE: Topband: 160 4 square

 Hello All
    JC, Greg knows quite a bit about receiving on 160 meters as he has had a
Hi-Z 8 element array for some years now. Actually he has done quite well
with it. Especially when he was neighbors with our dear departed friend N4NN
in Florida.
   JC, I have a question. If the Waller flag does not respond to vertical
signals why do you have to detune your vertical tower? The second part of my
question is if you do not have any local power line noises covering vertical
signals what advantage would a horizontal RX antenna be?

Lee    K7TJR

-----Original Message-----
From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of JC
Sent: Sunday, August 27, 2017 8:05 PM
To: 'GaryK9GS' <garyk9gs at wi.rr.com>; 'Greg' <n4cc at windstream.net>; 'topband'
<topband at contesting.com>
Subject: Re: Topband: 160 4 square

HI Greg

You need to detune the tower and the 4 square will work fine. But if you
want to have a good RX you need a Horizontal Waller Flag at 140ft or more.

You can  see the two webinars about Waller Flag at  www.wwrof.org archives

http://wwrof.org/webinar-archive/n4is-waller-flag-construction/

http://wwrof.org/webinar-archive/high-performance-rx-antennas-for-a-small-lo
t/

Doug NX4D 160m DXCC is # 304 confirmed, from a 1/5 acre lot, I started 3
years later with a Waller Flag and am at #293 confirmed. I sure mist a 4
square for TX ,. because since 2006 I've heard 316 countries on 160m from my
acre city lot in Fort Lauderdale on the last 10 years. 

Noise is very high here on the city

The best way you can destroy the station for RX on low bands is to use
elevated radials and NOT DETUNE IT during RX. 

The concept is  simple! All your wires makes only one receiving system. It
is necessity to keep all of them clean.

Performance is subjective, if you have nothing to compare you never know
what you are missing.

If you listen only vertical you are missing 50% of the band.

Regards
JC
N4IS

-----Original Message-----
From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of GaryK9GS
Sent: Sunday, August 27, 2017 5:51 PM
To: Greg <n4cc at windstream.net>; 'topband' <topband at contesting.com>
Subject: Re: Topband: 160 4 square

Take a look at the K3LR website.  This is essentially what Tim does, only
instead of a 4-square, his array is a 5 element parasitic array with three
active elements.  K3LR just gave a presentation on his station this weekend
for the Society of Midwest Contesters and this was mentioned.

73,
Gary K9GS
-------- Original message --------From: Greg <n4cc at windstream.net> Date:
8/27/17  1:56 PM  (GMT-06:00) To: 'topband' <topband at contesting.com>
Subject: Topband: 160 4 square Question for the group...

>From a 140 foot freestanding tower, I will suspend 4 pieces of phillystran
90 degrees apart from the top of the tower.  Antenna wire will be attached
to the phillystran such that verticals will be dropped to create a 4 square.
I will have as much vertical length as practical and still obtain the 4
square spacing required -- but the vertical length certainly will not be
close to a quarter wave.  The intent is to use the verticals as a 4 square.
In thinking of ways to increase the electrical length, should I run wire
back toward the tower from the top of the vertical section to get the full
1/4 or use a T with wire going back toward the tower and down the
phillystran to create a "top hat" effect -- or does it matter?  Obviously
this is a compromise but hopefully still an effective antenna with
directional gain.  Thanks in advance for your thoughts.  73, Greg-N4CC
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