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Old June 27th 05, 05:24 PM
John Smith
 
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Chris:

Well, I certainly can see that your claim it is two 1:1 baluns on a
single core is technically accurate--the primaries are in parallel and
their secondaries are in series... that seems clear enough that it
cannot be argued. I can't imagine all NOT to be in agreement on this
point.

However, with no electrical connection (transmission line) existing
between primary/secondary, and the voltage and current only conducted
between these windings by a magnetic flux--I CAN'T see how a "true"
balun can be argued, clearly--as opposed to "rf transformer."

But, I am giving this thought--as I am sure are others... I never
thought about the humble "balun"/"rf transformer" in some of these ways
before--possibly I am not alone... either and anyway, I enjoy the
thinking you have established here...

John

"Chris Trask" wrote in message
link.net...

1. That it is simply a 2:1 transformer with an isolated primary and
secondary?


No. It is a pair of 1:1 transformers on a single core. I can make
it
work equally well by making the two transformers on separate cores. I
can
also make it with a pair of equal length coaxial cables. Both of
these
realisations defeat his claim that it is a 2:1 transformer. But at
the same
time, neither of them answer his claim that it is impossible to make a
4:1
current balun on a single core with a pair of 1:1 transformers.


2. That it is not a true transmission line transformer, because your
transmission-line windings are not being fed with opposite polarities
across the *same* end?


This isn't even a gray area. We're making a BALUN, in other words
a
transformer that has an UNbalanced port and a BALanced port, and in
this
case fully meeting the definition of a current balun. If we were to
accept
the above statement, then we would have no choice except to conclude
that in
no circumstances could we make a BALUN with transmission line
transformers
because in all cases of BALUNs one port is fed unbalanced.

Making transmission line transformers is not difficult, although
Tom is
making it appear as though it's some sort of great mustery. For a
length of
transmission line that is sufficiently short with respect to
wavelength,
meaning less than an eighth of a wavelength in practice, the following
rules
are observed:

1. The voltage across the one conductor is equal to the
voltage of the other conductor, both in magnitude and
in phase.

2. The current in the one conductor is equal in magnitude
but oppostite in phase to the current in the other
conductor.

These basic understandings of transmission line transformers are well
established and understood. Gary Breed brought the concept down to
the
essentials in:

Breed, Gary, "Transmission Line Transformer Basics," Applied
Microwave & Wireless, Vol. 10, No. 4, May 1998, p. 60.

It all comes down to a difference between what is known by way of
established theory and practice versus trying to convince people that
everything we know is wrong.

Chris

,----------------------. High Performance Mixers and
/ What's all this \ Amplifiers for RF Communications
/ extinct stuff, anyhow? /
\ _______,--------------' Chris Trask / N7ZWY
_ |/ Principal Engineer
oo\ Sonoran Radio Research
(__)\ _ P.O. Box 25240
\ \ .' `. Tempe, Arizona 85285-5240
\ \ / \
\ '" \ IEEE Senior Member #40274515
. ( ) \
'-| )__| :. \ Email:
| | | | \ '.
http://www.home.earthlink.net/~christrask
c__; c__; '-..'.__

Graphics by Loek Frederiks

"Ian White GM3SEK" wrote in message
...
Chris Trask wrote:

It's not a matter of whether I disagree with him or not. It's a

matter
of him standing on a cybersoapbox and declaring to the world in
numerous
ways that such a thing cannot work and that only his analysis of how
it

can
and cannot work is valid. He can't deny that he claimed that it was
impossible, so now he has to prove that the solution cannot possibly
work
the way that he knows that it cannot work. Whatever.


Please skip the personal rhetoric, and tell us how you respond to his
two main technical points about your transformer:

1. That it is simply a 2:1 transformer with an isolated primary and
secondary?

2. That it is not a true transmission line transformer, because your
transmission-line windings are not being fed with opposite polarities
across the *same* end?


--
73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek




  #2   Report Post  
Old June 27th 05, 09:22 PM
Chris Trask
 
Posts: n/a
Default


However, with no electrical connection (transmission line) existing
between primary/secondary, and the voltage and current only conducted
between these windings by a magnetic flux--I CAN'T see how a "true"
balun can be argued, clearly--as opposed to "rf transformer."


I left out the word "current". My balun is a proper current balun as it
meets the formal definition, which is that it maintains currents at the
output terminals that are equal in magnitude and opposite in phase
regardless of potentials at the output terminals with respect to the ground
connection on the unbalanced side. You can find this definition in less
strict form in the ARRL handbook, such as 1991 pages 16.8-16.9.

The single core Guanella 4:1 current balun meets this definition but
only for floating loads. Anything other than that and the two transformers
need to be on separate cores.

Chris

,----------------------. High Performance Mixers and
/ What's all this \ Amplifiers for RF Communications
/ extinct stuff, anyhow? /
\ _______,--------------' Chris Trask / N7ZWY
_ |/ Principal Engineer
oo\ Sonoran Radio Research
(__)\ _ P.O. Box 25240
\ \ .' `. Tempe, Arizona 85285-5240
\ \ / \
\ '" \ IEEE Senior Member #40274515
. ( ) \
'-| )__| :. \ Email:
| | | | \ '.
http://www.home.earthlink.net/~christrask
c__; c__; '-..'.__

Graphics by Loek Frederiks

"John Smith" wrote in message
...
Chris:

Well, I certainly can see that your claim it is two 1:1 baluns on a
single core is technically accurate--the primaries are in parallel and
their secondaries are in series... that seems clear enough that it
cannot be argued. I can't imagine all NOT to be in agreement on this
point.

However, with no electrical connection (transmission line) existing
between primary/secondary, and the voltage and current only conducted
between these windings by a magnetic flux--I CAN'T see how a "true"
balun can be argued, clearly--as opposed to "rf transformer."

But, I am giving this thought--as I am sure are others... I never
thought about the humble "balun"/"rf transformer" in some of these ways
before--possibly I am not alone... either and anyway, I enjoy the
thinking you have established here...

John

"Chris Trask" wrote in message
link.net...

1. That it is simply a 2:1 transformer with an isolated primary and
secondary?


No. It is a pair of 1:1 transformers on a single core. I can make
it
work equally well by making the two transformers on separate cores. I
can
also make it with a pair of equal length coaxial cables. Both of
these
realisations defeat his claim that it is a 2:1 transformer. But at
the same
time, neither of them answer his claim that it is impossible to make a
4:1
current balun on a single core with a pair of 1:1 transformers.


2. That it is not a true transmission line transformer, because your
transmission-line windings are not being fed with opposite polarities
across the *same* end?


This isn't even a gray area. We're making a BALUN, in other words
a
transformer that has an UNbalanced port and a BALanced port, and in
this
case fully meeting the definition of a current balun. If we were to
accept
the above statement, then we would have no choice except to conclude
that in
no circumstances could we make a BALUN with transmission line
transformers
because in all cases of BALUNs one port is fed unbalanced.

Making transmission line transformers is not difficult, although
Tom is
making it appear as though it's some sort of great mustery. For a
length of
transmission line that is sufficiently short with respect to
wavelength,
meaning less than an eighth of a wavelength in practice, the following
rules
are observed:

1. The voltage across the one conductor is equal to the
voltage of the other conductor, both in magnitude and
in phase.

2. The current in the one conductor is equal in magnitude
but oppostite in phase to the current in the other
conductor.

These basic understandings of transmission line transformers are well
established and understood. Gary Breed brought the concept down to
the
essentials in:

Breed, Gary, "Transmission Line Transformer Basics," Applied
Microwave & Wireless, Vol. 10, No. 4, May 1998, p. 60.

It all comes down to a difference between what is known by way of
established theory and practice versus trying to convince people that
everything we know is wrong.

Chris

,----------------------. High Performance Mixers and
/ What's all this \ Amplifiers for RF Communications
/ extinct stuff, anyhow? /
\ _______,--------------' Chris Trask / N7ZWY
_ |/ Principal Engineer
oo\ Sonoran Radio Research
(__)\ _ P.O. Box 25240
\ \ .' `. Tempe, Arizona 85285-5240
\ \ / \
\ '" \ IEEE Senior Member #40274515
. ( ) \
'-| )__| :. \ Email:
| | | | \ '.
http://www.home.earthlink.net/~christrask
c__; c__; '-..'.__

Graphics by Loek Frederiks

"Ian White GM3SEK" wrote in message
...
Chris Trask wrote:

It's not a matter of whether I disagree with him or not. It's a

matter
of him standing on a cybersoapbox and declaring to the world in
numerous
ways that such a thing cannot work and that only his analysis of how
it

can
and cannot work is valid. He can't deny that he claimed that it was
impossible, so now he has to prove that the solution cannot possibly
work
the way that he knows that it cannot work. Whatever.


Please skip the personal rhetoric, and tell us how you respond to his
two main technical points about your transformer:

1. That it is simply a 2:1 transformer with an isolated primary and
secondary?

2. That it is not a true transmission line transformer, because your
transmission-line windings are not being fed with opposite polarities
across the *same* end?


--
73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek






  #3   Report Post  
Old June 27th 05, 09:34 PM
W8JI
 
Posts: n/a
Default

I left out the word "current". My balun is a proper current balun as
it
meets the formal definition, which is that it maintains currents at the

output terminals that are equal in magnitude and opposite in phase
regardless of potentials at the output terminals with respect to the
ground
connection on the unbalanced side. You can find this definition in
less
strict form in the ARRL handbook, such as 1991 pages 16.8-16.9.

I agree.It just isn't a transmission line balun, nor an optimum design
for most applications.

The single core Guanella 4:1 current balun meets this definition
but
only for floating loads. Anything other than that and the two
transformers
need to be on separate cores.

I agree again. That's what I've been saying all along.

There we have it. Problem solved except for calling transmission lines
transformers, and transformers transmission lines.

73 Tom

  #4   Report Post  
Old June 28th 05, 12:56 PM
W8JI
 
Posts: n/a
Default

However, with no electrical connection (transmission line) existing
between primary/secondary, and the voltage and current only conducted
between these windings by a magnetic flux--I CAN'T see how a "true"
balun can be argued, clearly--as opposed to "rf transformer."


But, I am giving this thought--as I am sure are others... I never
thought about the humble "balun"/"rf transformer" in some of these ways

before--possibly I am not alone... either and anyway, I enjoy the
thinking you have established here...

Aw comen on now John. Every single link coupled transformer from the
1900's to today works on the principle, as do link coupled tuners or
matching systems.

Many solid state amplifiers, as amatter of fact MOST HF solid state
amps use a primary/secondary transformer to couple unbalanced loads to
the PA transistors balanced source.

As a matter of fact many use a similar circuit as this "novel
invention". The ALM-500 for example used series secondarys for a period
of time, as did Henry amps.

I had a push-pull 810 amplifier that used the same system to drive the
grids of the triodes in 1964 or 65.

Using a transformer with interleaved or coaxial windings is about as
new as the first power transmission with AC power.

The only thing new or novel about Chris' "invention" is he has
redefined transmission line to include flux-coupled windings that do
not convey energy via TEM (transverse electiomagnetic) waves like the
normal transmission line we use.

Making up a new definition is not the same as producing a new or novel
invention. This is almost like the new invention call Fractal antennas
or E-H antennas that don't use "old" technology!

73 Tom

  #5   Report Post  
Old June 28th 05, 04:33 PM
Fred W4JLE
 
Posts: n/a
Default

John's big thing in life is to do an internet search on any current subject,
he then regurgitates it so he can appear to have something to add to the
discussion.

"W8JI" wrote in message
oups.com...
Aw comen on now John. Every single link coupled transformer from the
1900's to today works on the principle, as do link coupled tuners or
matching systems.





  #6   Report Post  
Old June 28th 05, 06:46 PM
Cecil Moore
 
Posts: n/a
Default

W8JI wrote:
Making up a new definition is not the same as producing a new or novel
invention. This is almost like the new invention call Fractal antennas
or E-H antennas that don't use "old" technology!


This thread has got me wondering if "Ruthroff" balun is the
same as "voltage" balun and if "Guanella" balun is the same as
"current" balun, as was explained to me once by a balun guru.
--
73, Cecil http://www.qsl.net/w5dxp


----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups
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  #7   Report Post  
Old June 29th 05, 05:59 AM
Larry Benko
 
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Default

I just happened upon an App. note written by Philips
Semiconductors (ECO6907) titled "Design of HF wideband power
transformers" which states for both 4:1 and 9:1 transmission
line transformers that they CAN be wound on a single core if
desired for certain conditions (see sections 6.3, 6.4 and 6.6).

http://www.semiconductors.philips.co...es/ECO6907.pdf

73,
Larry, W0QE
  #8   Report Post  
Old June 29th 05, 10:08 AM
Harold E. Johnson
 
Posts: n/a
Default


"Larry Benko" wrote in message
...
I just happened upon an App. note written by Philips
Semiconductors (ECO6907) titled "Design of HF wideband power
transformers" which states for both 4:1 and 9:1 transmission
line transformers that they CAN be wound on a single core if
desired for certain conditions (see sections 6.3, 6.4 and 6.6).


http://www.semiconductors.philips.co...es/ECO6907.pdf

73,
Larry, W0QE


And, that comes in TWO parts. ECO6907 and ECO 7213. BOTH wonderful
resources, and both apply to the discussion here. (They DO call them
"conventional transformers" and not Baluns.)

W4ZCB


  #9   Report Post  
Old July 1st 05, 10:09 PM
KD5NWA
 
Posts: n/a
Default

The article calls all of the devices transformers, not "conventional
transformers" including the phase inverter that is a TLT.

  #10   Report Post  
Old July 2nd 05, 02:18 AM
Harold E. Johnson
 
Posts: n/a
Default


"KD5NWA" wrote in message
oups.com...
The article calls all of the devices transformers, not "conventional
transformers" including the phase inverter that is a TLT.


Actually, if you'll take a read of part 2 of the application note ECO6907,
(ECO7213, which I referenced) It specifically states that part 1 was devoted
entirely to the design of *transmission line transformers*, which had the
advantage of the widest possible bandwidth, but several disadvantages as
well. Therefore, part 2 considers the possibility of applying a
*conventional transformer* if those constraints were undesireable.

Sheeeeeeeeesh!
W4ZCB




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