Re: Topband: Inverted L improvement question - Part 2

[Brian Miller]

Hi Grant and Todd

I suggest there is also potential for a 4th problem - mutual coupling
between the vertical wire and supporting tree.  Any such coupling would be
smaller for the 43 ft vertical if it was located further away from the tree.

It would be interesting to see if there is any noticeable change in the SWR
curve and performance by increasing the distance between the vertical wire
and tree trunk. But I also appreciate that space and other factors may
preclude Todd from doing this. 

73, Brian VK3MI

Message: 11
Date: Sat, 29 Dec 2018 09:00:03 -0800
From: Grant Saviers 
To: Todd Goins , TopBand List

Subject: Re: Topband: Inverted L improvement question - Part 2
Message-ID: 
Content-Type: text/plain; charset=utf-8; format=flowed

Problem #1. The swr indicates about a 140Khz plus < 2:1 bandwidth (2 * 
1880-1810) which implies a high radial resistance.  Are the elevated 
radials fully insulated from trees, not contacting foliage, etc?  Add 
three more.
Problem #2.  Your coiled coax choke may be making things worse.  Check 
out the just released designs from K9YC and build one.  17 turns RG400 
on one FT240-31.
Problem #3.  The increased gain of the T may be causing BCB desense of 
the 7300.  You need a BCB filter. Also the poor choke may be letting a 
lot of common mode noise into the antenna.

Grant KZ1W


_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Topband Digest, Vol 192, Issue 33

[Chuck Dietz]

Unfortunately, most are just deleting the conversation without reading it
like I usually do, because of the title...

Chuck W5PR

On Sat, Dec 29, 2018 at 5:31 PM Mike Waters  wrote:

> On Sat, Dec 29, 2018, 8:58 AM  wrote:
>
> > ... to bring this discussion to the high level technical discussion this
> > group is used to
>
>
> YE! :-)
>
> 73, Mike
> www.w0btu.com
> _
> Searchable Archives: http://www.contesting.com/_topband - Topband
> Reflector
>
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Topband Digest, Vol 192, Issue 33

[Mike Waters]

On Sat, Dec 29, 2018, 8:58 AM  wrote:

> ... to bring this discussion to the high level technical discussion this
> group is used to


YE! :-)

73, Mike
www.w0btu.com
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Inverted L improvement question - Part 2

[Mike Waters]

Exactly! You have a lot of loss in your ground (or something), Todd.

Perhaps it's the lack of a proper feedline choke.

73, Mike
www.w0btu.com

On Sat, Dec 29, 2018, 11:00 AM Grant Saviers  wrote:

> Problem #1. The swr indicates about a 140Khz plus < 2:1 bandwidth (2 *
> 1880-1810) which implies a high radial resistance.  Are the elevated
> radials fully insulated from trees, not contacting foliage, etc?  Add
> three more.
> Problem #2.  Your coiled coax choke may be making things worse.  Check
> out the just released designs from K9YC and build one.  17 turns RG400
> on one FT240-31.
> Problem #3.  The increased gain of the T may be causing BCB desense of
> the 7300.  You need a BCB filter. Also the poor choke may be letting a
> lot of common mode noise into the antenna.
>
> Grant KZ1W
>
>
>
> On 12/28/2018 19:39 PM, Todd Goins wrote:
> > A person emailed me to ask if I could take SWR readings at the rig
> without
> > a tuner. Since my antenna analyzer is non-op due to the AM station
> nearby.
> > The feedline is about 140' of LMR-240.
> >
> > Here is the indicated SWR at the 7300:
> > 1.810 1.2:1
> > 1.830 1.3:1
> > 1.850 1.5:1
> > 1.870 1.8:1
> > 1.900 2.3:1
> > 1.940 3.0:1
> >
> > Todd - NR7RR
> >
> > On Fri, Dec 28, 2018 at 7:30 PM Todd Goins  wrote:
> >
> >> Charlie,
> >>
> >> Yeah, I know the 100w is not ideal. This is night #2 with the elevated
> >> radials on the 100' vertical. I spent every day last week trying to use
> the
> >> 100' vertical against my buried radial field. It was horrible on
> transmit
> >> and mostly deaf (high noise) on receive. The attenuator didn't help, it
> >> just isn't hearing stations. My 43' vertical top loaded with 90' of
> >> horizontal wire is way, way more effective.
> >>
> >> I'm using a 230' BOG as my primary receive antenna right now but I can
> >> switch in the transmit antenna to listen just by throwing a switch.
> >>
> >> I'll stick with this 100' antenna for a while and try to use it this
> >> weekend on the Stew Perry but I have a feeling I'll be back with the 43'
> >> before it is over.
> >>
> >> Thanks,
> >> 73
> >> Todd - NR7RR
> >>
> >> On Fri, Dec 28, 2018 at 7:19 PM charlie carroll  wrote:
> >>
> >>> Todd:
> >>> So, I might shorten the antenna up a bit to get the lowest SWR point a
> >>> bit higher in the band.  But, as it sits right now, your SWR is not
> >>> indicating a problem.  You're talking only a 100 watts which gives you
> at
> >>> least 1 strike.  I would play with it as is for a few days and get some
> >>> idea as to how well you are hearing and how well you are transmitting.
> >>>
> >>> Without detailing you, 160 is a place where you need patience and/or a
> >>> low-noise receiving antenna.  Plus, you also need to know whether you
> are
> >>> being affected by local noise sources.  Another reason why I encourage
> you
> >>> to spend more time evaluating the antenna.
> >>>
> >>> 73 charlie, k1xx
> >>>
> >>> On 12/28/2018 10:07 PM, Todd Goins wrote:
> >>>
> >>> Hi Charlie,
> >>>
> >>> I can measure SWR at the rig. Feedline is about 140' of LMR240 coax.
> >>>
> >>> SWR at:
> >>> 1.810 1.2:1
> >>> 1.830 1.3:1
> >>> 1.850 1.5:1
> >>> 1.870 1.8:1
> >>> 1.900 2.3:1
> >>> 1.940 3.0:1
> >>>
> >>> I wasn't too worried about the choke situation but I connected in-line
> >>> what I had on hand, figured it wouldn't hurt. Mike had just asked what
> I
> >>> was using so I let him know. I'm not having any symptoms of RF in the
> shack
> >>> but I'm only running 100 watts.
> >>>
> >>> 73,
> >>> Todd - NR7RR
> >>>
> >>>
> >>> On Fri, Dec 28, 2018 at 6:56 PM charlie carroll  wrote:
> >>>
>  Todd:
>  So, what do you expect the air-wound choke to do for you?  Many, many,
>  many antennas operate fine without a choke.  Don't get yourself
> wrapped
>  around the axle that the antenna won't work without a "correct" choke.
> 
>  What's SWR are you measuring at the transmitter?  How long is the
>  feedline?  Sure, it would be better to know what the Resistance and
>  reactance are.  But, SWR will give you some idea as to where you are
> at.  I
>  think right now, you don't really know what your ground truth is.
> Tell me
>  the SWR at 1.8, 1.85, 1.9, etc.
> 
>  73 charlie, k1xx
> 
> 
> 
>  On 12/28/2018 9:30 PM, Todd Goins wrote:
> 
>  Hi Mike,
> 
>  Oh, I would totally believe that the air-wound choke is ineffective at
>  160m. It just happens to be what I had available to use when I rigged
> up
>  the elevated radials in the cold rain yesterday. I figured I'd put it
> in
>  line just in case.
> 
>  Thanks for the choke links, I will read the info on those sites.
> 
>  The air-wound choke is what I'm using when I'm feeding the antenna
> using
>  the elevated radials. When I was testing using my buried radial field
> it is
>  a different setup. There I have a DX Engineering radial plate that
> neatly
>  ties everything (remote tuner, and DX 

Re: Topband: Fwd: Topband Digest -- RX Antenna Performance

[Clive GM3POI]

George your last point is a good one. Take any vertical array such an 8 or 9
circle array and point it at a resonant electrical 1/4 wave vertical. The
pattern will be destroyed at 200 or 500ft. The TX antenna has to be isolated
above ground for the RX antenna to perform properly. So I also suggest that
the placing of the RX array should also be a consideration.   HNY Clive
GM3POI

-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of GEORGE
WALLNER
Sent: 29 December 2018 19:44
To: Mike Waters; Wes Stewart; topband
Subject: Re: Topband: Fwd: Topband Digest -- RX Antenna Performance

Mike,
N4IS (JC) does know what he is talking about.
His Waller Flag, however, can be vertical or horizontal. The Horizontal WF 
(HWF) is certainly a class above all other loops, provided it is more than 
100' up. But you can have a Vertical WF at any height -- in fact lower is 
better. Not as good as HWF, but still a very good RX antenna.
JC makes a very crucial point: the WF does have a much narrower front lobe 
and has minimal side lobes, because it has two elements. You can not get 
this narrow pattern with a single loop. Any single element loop will have a 
more-or-less cardioid radiation pattern, which translates to a RDF  of 7 to 
8 dB. To get a higher RDF, you need two elements.
On JC's recommendation, I built a phased array of two delta loops on a small

island and tested its "radiation" pattern. The video at 
https://www.youtube.com/watch?v=JMujut_5FdY=71s was shot from a drone that

carried a small 1.8 MHz transmitter. The audio is from the receiver 
connected to the antenna (the two vertical poles hold the apexes of the two 
delta loops). The video starts in front of the antenna (maximum signal). At 
90 degrees (the side of the antenna) the signal is almost zero. As the drone

moves towards the rear, there are two weak side lobes, and then almost no 
signal from the rear. This pattern is consistent with the NEC model of the 
same antenna. This antenna has a 150' foot-print, which is much smaller than

a Beverage with similar performance.
Another crucial point: I have built many RX antennas of various designs. I 
have found that their performance varied a great deal based on the 
environment. The same antenna would work great in one place and would be 
terrible somewhere else. Local conditions (the ground, wires in the ground, 
nearby antennas, etc.) can change the radiation pattern and can induce 
noise, rendering an antenna that models great useless. If you build a well 
established design, like a K9AY or SAL, and it does not perform according to

its specifications, see what is around it. These antennas have very low gain

and even a very small amount of noise can swamp the weak signals they 
produce.
73,
George
AA7JV/C6AGU




On Fri, 28 Dec 2018 19:50:52 -0600
  Mike Waters  wrote:
> Hi Wes,
>
> I'm 95% certain that N4IS knows what he's talking about here. I've been
> reading the posts on this reflector for years, and there's a few experts
> that stand above and beyond the rest of us. ;-)
>
> He invented the Waller flag, IIRC; you might want to look into that. He
has
> written much about it, both here and on his website. If I were a young man
> again, I would put one on a tower and rotor in a heartbeat. It's like
> having a one-wavelength Beverage that's rotatable.
>
> Now, the Waller is more critical than many other good RX antennas, but
with
> your years of hands-on electronics experience I have no doubt that
wouldn't
> be an issue for you.
>
> You might want to start with Dr. Gary Breed's (K9AY) improved design
first.
> I forget the URL of his website.
>
> Just my $0.02 worth. ;-)
>
> 73, Mike
> www.w0btu.com  
>
> -- Forwarded message -
>From: 
> Date: Fri, Dec 28, 2018 at 2:44 PM
> Subject: Re: Topband: Topband Digest, Vol 192, Issue 33
> To: Jay Terleski , 
>
>
> Jay
>
> The SAL is only one electrical equivalent loop with 9 db RDF, the Waller
>Flag  has 2 flags in phase with 11.5 db RDF.
>
> It is not on the same class.  Sorry but I am been honest here, both
antennas
> need the tower to be detuned to work.
>
> The invention of a BALUN just transfer the impedance replacing a resistor
> 1000 ohms to load the loop as any FLAG, the other BALUN you call a special
> name to patent, it is just a simple BALUN, it is just the feed line , the
> SAL does have one resistor and one feed point,  the two vertical wires
works
> like a very  short transmission line. And it removed does not affect
> anything, You own engineer admitted that.
>
> To prove that it is no the same class,  check the side null, two flags can
> provide a deep null on each side , 30 db , and 20 db F/B.
>
> Does your SAL provide side null, 82 degree front lob,. 11.5 db RDF and it
is
> ground independent?  NO.
>
> Can you elevate it and turn.it? NO
>
> The SAL is grounded dependent and can not be elevated and turned..  Sorry
> the SAL is identical a K9AY, build them side by 

Re: Topband: Inverted L improvement question - Part 2

[Todd Goins]

On Sat, Dec 29, 2018 at 8:59 AM Grant Saviers  wrote:

> Problem #1. The swr indicates about a 140Khz plus < 2:1 bandwidth (2 *
> 1880-1810) which implies a high radial resistance.  Are the elevated
> radials fully insulated from trees, not contacting foliage, etc?  Add
> three more.
> Problem #2.  Your coiled coax choke may be making things worse.  Check
> out the just released designs from K9YC and build one.  17 turns RG400
> on one FT240-31.
> Problem #3.  The increased gain of the T may be causing BCB desense of
> the 7300.  You need a BCB filter. Also the poor choke may be letting a
> lot of common mode noise into the antenna.
>
> Grant KZ1W
>

Hello Grant,

Thanks for the input.  I've made a couple of modifications this morning. I
can't make that choke today because I don't have the FT240-31 but I'll
check out that design and look into ordering the parts. Sounds easy enough
to build though.

Yes, the BCB signal on the large wire is intense. When attempting to use it
as a receiving antenna I have to run the attenuator and often dial out some
RF Gain as well. Nasty stuff. I'll see about getting a BCB filter if for
nothing else but to be able to use the antenna analyzer. I've looked at
many designs I could build but they almost all have a cutoff freq above the
160m band. Not what I need...

I raised the feedpoint to about 12' above ground surface and the radials
are similarly elevated for their 130' length. The radial wire is insulated
but it does use some (leafless) tree branches as supports. I have no way to
add three more elevated 130' radials at this time. Good idea though.

Raising the feedpoint did change the SWR readings at the rig. The 2:1 range
is quite a bit narrower, which is an improvement, I guess.  Here are the
new readings.

Indicated SWR at the 7300:
1.810 1.3:1
1.830 1.6:1
1.850 1.8:1
1.870 2.3:1
1.900 2.8:1
1.940 greater than 5:1

I'm looking forward to trying it out tonight in the Stew Perry. I still
have the 43' L to fall back on if the performance has not improved.

Thanks for the help.
73,
Todd - NR7RR

>
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Fwd: Topband Digest -- RX Antenna Performance

[GEORGE WALLNER]

Mike,
N4IS (JC) does know what he is talking about.
His Waller Flag, however, can be vertical or horizontal. The Horizontal WF 
(HWF) is certainly a class above all other loops, provided it is more than 
100' up. But you can have a Vertical WF at any height -- in fact lower is 
better. Not as good as HWF, but still a very good RX antenna.
JC makes a very crucial point: the WF does have a much narrower front lobe 
and has minimal side lobes, because it has two elements. You can not get 
this narrow pattern with a single loop. Any single element loop will have a 
more-or-less cardioid radiation pattern, which translates to a RDF  of 7 to 
8 dB. To get a higher RDF, you need two elements.
On JC's recommendation, I built a phased array of two delta loops on a small 
island and tested its "radiation" pattern. The video at 
https://www.youtube.com/watch?v=JMujut_5FdY=71s was shot from a drone that 
carried a small 1.8 MHz transmitter. The audio is from the receiver 
connected to the antenna (the two vertical poles hold the apexes of the two 
delta loops). The video starts in front of the antenna (maximum signal). At 
90 degrees (the side of the antenna) the signal is almost zero. As the drone 
moves towards the rear, there are two weak side lobes, and then almost no 
signal from the rear. This pattern is consistent with the NEC model of the 
same antenna. This antenna has a 150' foot-print, which is much smaller than 
a Beverage with similar performance.
Another crucial point: I have built many RX antennas of various designs. I 
have found that their performance varied a great deal based on the 
environment. The same antenna would work great in one place and would be 
terrible somewhere else. Local conditions (the ground, wires in the ground, 
nearby antennas, etc.) can change the radiation pattern and can induce 
noise, rendering an antenna that models great useless. If you build a well 
established design, like a K9AY or SAL, and it does not perform according to 
its specifications, see what is around it. These antennas have very low gain 
and even a very small amount of noise can swamp the weak signals they 
produce.

73,
George
AA7JV/C6AGU




On Fri, 28 Dec 2018 19:50:52 -0600
 Mike Waters  wrote:

Hi Wes,

I'm 95% certain that N4IS knows what he's talking about here. I've been
reading the posts on this reflector for years, and there's a few experts
that stand above and beyond the rest of us. ;-)

He invented the Waller flag, IIRC; you might want to look into that. He has
written much about it, both here and on his website. If I were a young man
again, I would put one on a tower and rotor in a heartbeat. It's like
having a one-wavelength Beverage that's rotatable.

Now, the Waller is more critical than many other good RX antennas, but with
your years of hands-on electronics experience I have no doubt that wouldn't
be an issue for you.

You might want to start with Dr. Gary Breed's (K9AY) improved design first.
I forget the URL of his website.

Just my $0.02 worth. ;-)

73, Mike
www.w0btu.com  


-- Forwarded message -
From: 
Date: Fri, Dec 28, 2018 at 2:44 PM
Subject: Re: Topband: Topband Digest, Vol 192, Issue 33
To: Jay Terleski , 


Jay

The SAL is only one electrical equivalent loop with 9 db RDF, the Waller
Flag  has 2 flags in phase with 11.5 db RDF.

It is not on the same class.  Sorry but I am been honest here, both antennas
need the tower to be detuned to work.

The invention of a BALUN just transfer the impedance replacing a resistor
1000 ohms to load the loop as any FLAG, the other BALUN you call a special
name to patent, it is just a simple BALUN, it is just the feed line , the
SAL does have one resistor and one feed point,  the two vertical wires works
like a very  short transmission line. And it removed does not affect
anything, You own engineer admitted that.

To prove that it is no the same class,  check the side null, two flags can
provide a deep null on each side , 30 db , and 20 db F/B.

Does your SAL provide side null, 82 degree front lob,. 11.5 db RDF and it is
ground independent?  NO.

Can you elevate it and turn.it? NO

The SAL is grounded dependent and can not be elevated and turned..  Sorry
the SAL is identical a K9AY, build them side by side and you will see it.

The HWF is at another level because cancel manmade noise and the increase on
signal to noise ratio improvement is 20 db or better.

You get what you pay for. I can tell you that the SAL is really a Snake Oil.
Work 300 countries with a SAL and I will give you some credit.

73.
JC


-Original Message-
From: Topband  On Behalf Of Jay Terleski
Sent: Friday, December 28, 2018 12:20 PM
To: topband@contesting.com
Subject: Re: Topband: Topband Digest, Vol 192, Issue 33

JC said,
The SAL is a good antenna, any directivity increases signal to noise ratio.
The RDF is 2 to 3 bd better than the vertical antenna, it means the
improvement on signal to noise ratio is about 6db.  You can dig 

Re: Topband: Inverted L improvement question - Part 2

[Grant Saviers]

Problem #1. The swr indicates about a 140Khz plus < 2:1 bandwidth (2 * 
1880-1810) which implies a high radial resistance.  Are the elevated 
radials fully insulated from trees, not contacting foliage, etc?  Add 
three more.
Problem #2.  Your coiled coax choke may be making things worse.  Check 
out the just released designs from K9YC and build one.  17 turns RG400 
on one FT240-31.
Problem #3.  The increased gain of the T may be causing BCB desense of 
the 7300.  You need a BCB filter. Also the poor choke may be letting a 
lot of common mode noise into the antenna.


Grant KZ1W



On 12/28/2018 19:39 PM, Todd Goins wrote:

A person emailed me to ask if I could take SWR readings at the rig without
a tuner. Since my antenna analyzer is non-op due to the AM station nearby.
The feedline is about 140' of LMR-240.

Here is the indicated SWR at the 7300:
1.810 1.2:1
1.830 1.3:1
1.850 1.5:1
1.870 1.8:1
1.900 2.3:1
1.940 3.0:1

Todd - NR7RR

On Fri, Dec 28, 2018 at 7:30 PM Todd Goins  wrote:


Charlie,

Yeah, I know the 100w is not ideal. This is night #2 with the elevated
radials on the 100' vertical. I spent every day last week trying to use the
100' vertical against my buried radial field. It was horrible on transmit
and mostly deaf (high noise) on receive. The attenuator didn't help, it
just isn't hearing stations. My 43' vertical top loaded with 90' of
horizontal wire is way, way more effective.

I'm using a 230' BOG as my primary receive antenna right now but I can
switch in the transmit antenna to listen just by throwing a switch.

I'll stick with this 100' antenna for a while and try to use it this
weekend on the Stew Perry but I have a feeling I'll be back with the 43'
before it is over.

Thanks,
73
Todd - NR7RR

On Fri, Dec 28, 2018 at 7:19 PM charlie carroll  wrote:


Todd:
So, I might shorten the antenna up a bit to get the lowest SWR point a
bit higher in the band.  But, as it sits right now, your SWR is not
indicating a problem.  You're talking only a 100 watts which gives you at
least 1 strike.  I would play with it as is for a few days and get some
idea as to how well you are hearing and how well you are transmitting.

Without detailing you, 160 is a place where you need patience and/or a
low-noise receiving antenna.  Plus, you also need to know whether you are
being affected by local noise sources.  Another reason why I encourage you
to spend more time evaluating the antenna.

73 charlie, k1xx

On 12/28/2018 10:07 PM, Todd Goins wrote:

Hi Charlie,

I can measure SWR at the rig. Feedline is about 140' of LMR240 coax.

SWR at:
1.810 1.2:1
1.830 1.3:1
1.850 1.5:1
1.870 1.8:1
1.900 2.3:1
1.940 3.0:1

I wasn't too worried about the choke situation but I connected in-line
what I had on hand, figured it wouldn't hurt. Mike had just asked what I
was using so I let him know. I'm not having any symptoms of RF in the shack
but I'm only running 100 watts.

73,
Todd - NR7RR


On Fri, Dec 28, 2018 at 6:56 PM charlie carroll  wrote:


Todd:
So, what do you expect the air-wound choke to do for you?  Many, many,
many antennas operate fine without a choke.  Don't get yourself wrapped
around the axle that the antenna won't work without a "correct" choke.

What's SWR are you measuring at the transmitter?  How long is the
feedline?  Sure, it would be better to know what the Resistance and
reactance are.  But, SWR will give you some idea as to where you are at.  I
think right now, you don't really know what your ground truth is.  Tell me
the SWR at 1.8, 1.85, 1.9, etc.

73 charlie, k1xx



On 12/28/2018 9:30 PM, Todd Goins wrote:

Hi Mike,

Oh, I would totally believe that the air-wound choke is ineffective at
160m. It just happens to be what I had available to use when I rigged up
the elevated radials in the cold rain yesterday. I figured I'd put it in
line just in case.

Thanks for the choke links, I will read the info on those sites.

The air-wound choke is what I'm using when I'm feeding the antenna using
the elevated radials. When I was testing using my buried radial field it is
a different setup. There I have a DX Engineering radial plate that neatly
ties everything (remote tuner, and DX Engineering Maxi-core Feedline
Current Choke) together at the feed point.

Thanks for the comments and info.
73,
Todd - NR7RR


On Fri, Dec 28, 2018 at 5:57 PM Mike Waters  
 wrote:


Hi Todd,

I'll bet the farm (if I had one) that your air-core choke is ineffective.
Take at look athttp://www.karinya.net/g3txq/chokes to see what I mean.

A very, very good common mode choke is the one I have on mine, 
fromhttp://audiosystemsgroup.com/RFI-Ham.pdf. There is no better material
written on this subject, either in print or on the Internet.

73, Mikewww.w0btu.com

On Fri, Dec 28, 2018 at 7:34 PM Todd Goins  
 wrote:


... I do have a common mode choke at (near) the feed point. It may or may
not
be effective at 160m. It does work on 10-80m. It is about 25' of RG-8 coax
wrapped around a 4" PVC pipe as a form. Perhaps not ideal... No RF 

Re: Topband: Topband Digest, Vol 192, Issue 33

[n4is]

Hi Dave , Bob and Jay

Fist of all thanks Dave and Bob to bring this discussion to the high level
technical discussion this group is used to, and my public sincere apologize
my friend  Jay for my emotional behavior that I regrets.

160m is a unique band that has only one noise component on sky wave, and it
is atmospheric noise, HF on the other hands has several other component's of
noise including cosmic rays. Going up in frequency atmospheric noise
decrease and cosmic rays increases.

We are in the low part of the solar cycle, propagation on most HF bands are
very poor, but not dead!. The Signal to noise ration is very important. I
was talking with my old friend PY5EG , Atilano Oms, about propagation , He
mentioned that he can hear 15m weak signals on his 72 FT boom 8 elements 15m
Yagi and  can not hear on his 5 element Yagi. The reason is the high
directivity g the large Yagi over the short Yagi. More directivity means you
can hear the signal above the noise on the higher RFD Yagi. Experiments on
VHF , 2m , 6m ant also EME systems, has the same results. 

On 160m when you don't have atmospheric noise and no ground wave (manmade
noise), the noise temperature can drop to 70 degree Kelvin, that is lower
than 144 Mhz. In this situation the signal to noise ratio is the Noise
figure of the RX system. However that situation is only present on few days
during the winter nights. Some atmospheric noise is known  by QRN at
distance., or normal propagation noise.

Bob is right about quiet locations, noise near -125 db is rare. Manmade
noise on ground wave is becoming a real problem.

The DRF or directivity improves signal to noise ratio at the antenna feed
point,  all electronic beyond this point deteriorate signal to noise ratio.
If the NF is the same equivalent temperature of the noise the deterioration
is 2.3 db S/N, on 160m  at 70 K the NF of 2 db deteriorates the signal to
noise ratio by 2.3 db. If he noise is above the NF of the system there is no
deterioration because the propagation noise dominates.

When noise is present li my city lot -85dbm average during the day, and my
best ever measured noise -100dBm. RDF plays a lot. 9 db RDF improves the S/N
ratio over 6 db from the vertical TX antenna that has 6 db RDF. Going to the
WF vertical or horizontal  with the same 11.5 db RDF, my 10 years measure
shows 10 db improvement. The HWF rejects mand made noise due a -90db gain on
the main direction, the ground waive is not amplified because it sits below
the MDS of the receiver.  Again, my measures show 20 or more db improve on
signal to noise ratio over my vertical. 

Places with different local noise has different results, if the noise is
s9+10 on -63 dBm, you can hear it on the HWF because it's above the MDS of
the receiver. This not considering common mode leak into the RX system, big
issue for all of us.

A good 4 square TX antenna, 4 vertical in phase has 11db to 12 db RDF, the
front lobe is 90 degree. One FLAG, EWE or K9AY, all loaded loops has a
cardioid patter similar 2 vertical ins phase, good front back  and a 120
degree front lobe. Two EWE or Flag or K9AY  phased has the same pattern or
RDF the 4 square, depending on the way it is build the RDF is 11 to 12 db, 4
verticals in phase like the TX array. It is simple like that. * verticals
has better RDF than 4 verticals, over 13 db RDF, and 60 degree front lobe.

It is easy to understand why a loaded loop self-phased by the resistor and
the transformer  has a cardioid pattern over  a large bandwidth , with a
small dimensions loop 1/10 of wave length the loaded loop can maintain the
patter from1 to 10 MHz ,  a smaller loaded loop 3 to 30 MHz, and a very
larger small loop to 300KHz  to 3 MHz .

A delta flag  has one horizontal wire and two wires inclined, let's say 45
degree. The current on the horizontal wire generates a current on the ground
180 degree out of phase and there is a cancelation between them , it is
really a transmit]ion  line, that is why a K9AY can mover the resistor and
transformer to the center, and switch directions using a relay.

The inclined wire current , let's say with a vector module 1, can be
decomposed by one vertical vector .707 module and another horizontal vector
also .707 module, sounds familiar in vectoral algebra. The horizontal
component cancel against the reflected waive from the ground, the vertical
component adds to the reflected wave from the ground like a real vertical.
The EWE, both horizontal wires are really a transition line   phasing the
two verticals.

The Delta Flag or FO0AAA, same thing, can be phased, two phased flag or WF,
is equivalent to 4 verticals. 4 Delta Flags are equivalent to 8 verticals,
you can get 13 db RDF , 60 degree front lobe. Very clean and at low angles.


In general a good phased vertical array outperform and beverage array
because the patter is cleaner and low angle radiation..

In the case of a SAL the vectoral description above apply, the two inclined
wire are really two verticals, the