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Dave:

I may be mistaken, but I believe Jasik, Balanis and Krause are all available (in various additions) from internet sources.

Ed McCann
AG6CX

Thank you! That is good to know. Forgive me, but as old school and 73
years 'wise', I much prefer a hard copy.

Dave - W?LEV

--
*Dave - W?LEV*
*Just Let Darwin Work*

Dave states:

1) Design the antenna by whatever means one chooses
2) Address the resulting matching as a circuit problem *
Good hard engineering and true to the physics of the problem like Krauss
and Balinas approach the problem as such, two separate solutions.

That is preferred when building an antenna for a fixed frequency with a specific radiation pattern.
If building a 4 element yagi for 14.1 mhz, that is exactly what I would do.
And a 50kw broadcast station cannot just put up a random wire and use an antenna tuner.

But most amateurs do not operate at a fixed frequency, and can tolerate the often
unnoticeable losses of reflections bouncing between the antenna feedpoint and antenna tuner.
Way more convenient than having a yard full of antennas for each favorite operating frequency.
The radiation pattern is pot luck and varies with frequency, but that can be part of the fun.

As Dave states in this post:
/g/nanovna-users/topic/76222973#16961
an antenna with a perfect match driven through 100 feet of RG8x
at 30 mhz loses 100%-63% = 37% of the power to attenuation in the coax.
As I show in posts 16960 and 16956 of that thread, if you then change frequency to where
the antenna has a 4:1 SWR, an antenna tuner at the rig (instead of at the antenna feedpoint)
will lose an extra 16% of the transmitter power due to the reflections in the lossy coax, on top of
Dave's perfect 37% loss. That 16% is pretty much unnoticeable to the operator at the far end.
If using ladder line instead of coax, these losses in the transmission line can be close to zero
even with very high SWR's. This is Walter Maxwell's primary argument throughout the book,
go ahead and use an antenna tuner at the rig to give the transmitter a proper match.

If you are concerned about antenna patterns, best to design the antenna
for a specific frequency. But if all you have is a 40 meter dipole (or a rain gutter),
it's worth using your antenna tuner to see if you can get a match on some of the other bands.

Jerry, KE7ER


On Thu, Sep 17, 2020 at 02:23 PM, David Eckhardt wrote:

Section 13.3 of the Maxwell tertise states (NOT Clerk Maxwell of the famous
'4-equations' which tied EM theory together in the late 19th Century!!):

" The antenna tuner really does tune the antenna to resonance, in
spite of opinions to the contrary of those who are unaware of the
principles of conju-gate matching. The tuner obtains a match, by which
all reactances throughout the entire antenna system are
canceled, including that of the non-res-onant antenna, thereby tuning it to
resonance."

*He addresses the antenna plus 'tuner' as a system. In that respect, yes,
the matching network or transmatch 'tunes' the system such that all the
impedances 'agree' without loss or reflections. HOWEVER, most antenna
engineers would not approach the problem differently, as such. *

*1) Design the antenna by whatever means one chooses
2) Address the resulting matching as a circuit problem *

*Good hard engineering and true to the physics of the problem like Krauss
and Balinas approach the problem as such, two separate solutions. The
"Maxwell" treatise seems to me a bit removed from good hard antenna theory
(with calculus et. al. the stuff that gives us headaches)! It's more of a
technician's 'cookbook' rather than a solid treatment of the subject.
Neither the Krauss nor Balinas or Jasik (which I do not have and wish I
did!) treatments address the circuitry to establish a match. All rigorous
antenna references (those two are my personal favorites) derive the feed
impedance and leave it there. All antenna engineers I've ever worked with,
including the Dr. Allen Love who designed some of the first Arecibo feeds,
approach the problem as the two-step solution, not including any adjustable
reactive components. These texts treat various methods of establishing a
match at the antenna and as a part of the antenna like the gamma, T, and
transmission line matches, but not the traditional concept of the
'transmatch'. Once the antenna array / radiating structure is designed and
the feed impedance is established, it's turned over to the circuit
designers. The 'Transmatch' belongs in the purview of the RF engineers /
RF circuit designers.*

*All rigorous RF design engineering texts DEFINE RESONANCE as +jX = -jX,
leaving nothing but pure resistance of the radiating structure (antennas)
or lumped system (resonant and tuned circuits circuits). Personally, I
will ALWAYS side on the side of rigorous treatment of the subject as taught
in the hard, rigorous engineering and physics texts. *

*Adjustment of various reactive components in NO WAY can alter the physical
structure of what is considered 'the antenna'!!! ! ! ..... *

*Dave - W?LEV *

I have been following this discussion.

If the tuner is attached directly at the antenna I refer to it as an antenna tuner.

If the tuner is connected to the transmission line feeding the antenna I refer to it as an antenna system tuner or transmatch.

I measured the resonant impedance of my 160 meter Inverted L this morning with my NanoVNA-F and it agrees with the readings taken with my N2PKVNA. The handheld NanoVNA-F is easier to use in the field since I don't have to bring a laptop.

Mike N2MS

I cut my teeth using coax and still do for my radio astronomy interests.
However, I use a 450 foot long doublet on 630 through 6 meters with a home
brew L-Network matching network. The feedline is parallel wire /
windowline transmission line. I don't worry much at all about losses in
the feedline or the matching network due to something other than 50 ±jX at
the input to the matching network. However, it's not a system for the
newbie to amateur radio HF operation.

Dave - W?LEV

On Fri, Sep 18, 2020 at 1:42 PM Jerry Gaffke via groups.io <jgaffke=
[email protected]> wrote:

Dave states:

1) Design the antenna by whatever means one chooses
2) Address the resulting matching as a circuit problem *
Good hard engineering and true to the physics of the problem like

Krauss

and Balinas approach the problem as such, two separate solutions.

That is preferred when building an antenna for a fixed frequency with a
specific radiation pattern.
If building a 4 element yagi for 14.1 mhz, that is exactly what I would do.
And a 50kw broadcast station cannot just put up a random wire and use an
antenna tuner.

But most amateurs do not operate at a fixed frequency, and can tolerate
the often
unnoticeable losses of reflections bouncing between the antenna feedpoint
and antenna tuner.
Way more convenient than having a yard full of antennas for each favorite
operating frequency.
The radiation pattern is pot luck and varies with frequency, but that can
be part of the fun.

As Dave states in this post:
/g/nanovna-users/topic/76222973#16961
an antenna with a perfect match driven through 100 feet of RG8x
at 30 mhz loses 100%-63% = 37% of the power to attenuation in the coax.
As I show in posts 16960 and 16956 of that thread, if you then change
frequency to where
the antenna has a 4:1 SWR, an antenna tuner at the rig (instead of at the
antenna feedpoint)
will lose an extra 16% of the transmitter power due to the reflections in
the lossy coax, on top of
Dave's perfect 37% loss. That 16% is pretty much unnoticeable to the
operator at the far end.
If using ladder line instead of coax, these losses in the transmission
line can be close to zero
even with very high SWR's. This is Walter Maxwell's primary argument
throughout the book,
go ahead and use an antenna tuner at the rig to give the transmitter a
proper match.

If you are concerned about antenna patterns, best to design the antenna
for a specific frequency. But if all you have is a 40 meter dipole (or a
rain gutter),
it's worth using your antenna tuner to see if you can get a match on some
of the other bands.

Jerry, KE7ER


On Thu, Sep 17, 2020 at 02:23 PM, David Eckhardt wrote:

Section 13.3 of the Maxwell tertise states (NOT Clerk Maxwell of the

famous

'4-equations' which tied EM theory together in the late 19th Century!!):

" The antenna tuner really does tune the antenna to resonance, in
spite of opinions to the contrary of those who are unaware of the
principles of conju-gate matching. The tuner obtains a match, by which
all reactances throughout the entire antenna system are
canceled, including that of the non-res-onant antenna, thereby tuning it

to

resonance."

*He addresses the antenna plus 'tuner' as a system. In that respect, yes,
the matching network or transmatch 'tunes' the system such that all the
impedances 'agree' without loss or reflections. HOWEVER, most antenna
engineers would not approach the problem differently, as such. *

*1) Design the antenna by whatever means one chooses
2) Address the resulting matching as a circuit problem *

*Good hard engineering and true to the physics of the problem like Krauss
and Balinas approach the problem as such, two separate solutions. The
"Maxwell" treatise seems to me a bit removed from good hard antenna

theory

(with calculus et. al. the stuff that gives us headaches)! It's more of a
technician's 'cookbook' rather than a solid treatment of the subject.
Neither the Krauss nor Balinas or Jasik (which I do not have and wish I
did!) treatments address the circuitry to establish a match. All rigorous
antenna references (those two are my personal favorites) derive the feed
impedance and leave it there. All antenna engineers I've ever worked

with,

including the Dr. Allen Love who designed some of the first Arecibo

feeds,

approach the problem as the two-step solution, not including any

adjustable

reactive components. These texts treat various methods of establishing a
match at the antenna and as a part of the antenna like the gamma, T, and
transmission line matches, but not the traditional concept of the
'transmatch'. Once the antenna array / radiating structure is designed

and

the feed impedance is established, it's turned over to the circuit
designers. The 'Transmatch' belongs in the purview of the RF engineers /
RF circuit designers.*

*All rigorous RF design engineering texts DEFINE RESONANCE as +jX = -jX,
leaving nothing but pure resistance of the radiating structure (antennas)
or lumped system (resonant and tuned circuits circuits). Personally, I
will ALWAYS side on the side of rigorous treatment of the subject as

taught

in the hard, rigorous engineering and physics texts. *

*Adjustment of various reactive components in NO WAY can alter the

physical

structure of what is considered 'the antenna'!!! ! ! ..... *

*Dave - W?LEV *

--
*Dave - W?LEV*
*Just Let Darwin Work*

On Tue, 8 Sep 2020 at 18:17, Anne Ranch <anneranch2442@...> wrote:

Can someone please shed some light on the definition of resonance in
conjunction with an antenna.



Let's agree that "resonance occurs when +/- jX is zero".

It does not take knowledge of x-degree differential equation , modelling ,
size of wire , moon phase etc.

It is applicable to ANY AC circuit, antenna included.

So is the circuit I published on another thread, with an inductor, a
capacitor and two resistors resonant at all frequencies? The reactance is
zero at all frequencies.

IF these parameters are SAME and EQUAL on harmonics , resonance @

harmonics will be observed.

Bur what about the case where zero reactance is seen not only on harmonics,
but at any frequency?

Dave.


--
Dr. David Kirkby,
Kirkby Microwave Ltd,
drkirkby@...

Telephone 01621-680100./ +44 1621 680100

Registered in England & Wales, company number 08914892.
Registered office:
Stokes Hall Lodge, Burnham Rd, Althorne, Chelmsford, Essex, CM3 6DT, United
Kingdom

Hi Dave-

It doesn't seem logical to differentiate between various Gamma, T-match, etc devices that are added solely to achieve an impedance match, and the use of lumped reactances like capacitors and inductors that are devices included for the exact same purpose. In either case, there is an "antenna system".

I think Walt Maxwell has taken a good view of the same situation from a different angle. His method works just fine and makes sense. That's not to say that looking at the "wires and rods" of the antenna separately from the matching network is "wrong", it's just different. And since both methods work just fine, neither would appear to be better or worse than the other. You prefer the approach taken by Krauss, Balinas and Jasik while I (and apparently some others) prefer Walt Maxwell's approach. We both achieve success, so there doesn't seem to be a problem! :-) It all just makes for a good discussion!

Very 73!

Tom AE5I

Dave - W0LEV wrote:

......Neither the Krauss nor Balinas or Jasik (which I do not have and wish I
did!) treatments address the circuitry to establish a match. All rigorous
antenna references (those two are my personal favorites) derive the feed
impedance and leave it there......

Correct, Tom. I just prefer to address each step of the way individually
as the rigorous texts do. You are correct in that either approach ends
in success.

Part of my bias stems from adjusting element lengths on a large Yagi to
establish a match. The element lengths and spacings were optimized for the
desired outcome, usually gain. So, don't go adjusting that for a match as
you are spoiling the design of the antenna. Address the matching problem
individually as a circuit problem, not "adjusting" the optimum antenna
design, itself, after it has been optimized in the design stage.

Dave - W?LEV

--
*Dave - W?LEV*
*Just Let Darwin Work*

Dave, I totally agree with you on the case you just presented of the yagi that has been optimized for a particular parameter (gain, for example)! If you've got the performance where you want it and you don't mind matching it with a network, then leave the antenna's performance alone and match it externally. On the other hand, if there is some reason that tinkering with the antenna first to improve the match is of high importance, then do it that way.... :-)

My thought is to use whichever approach gets you where you want to be with the best path to success.

Tom AE5I