John,
Yes, that's very nice. A pair of trifilar windings on a single core.
That's a variation of a 1:1 transmission line balun that I found in a
textbook. I've put the schematic and photo in a PDF file on my web page at:

http://www.home.earthlink.net/~chris...M1to1Balun.PDF

I'm qite certain that the two dots connecting the outer conductors to the
shield box are in error as in the photo the outer insulating jacket is not
broken. And those connections do not make sense, at least not immediately,
as the voltages and currents at that point are dissimilar. Also, there
should only be the one ground connection at the near end of the second
cable.

Seems to me that you could use this approach to make a nice, inexpensive
and lightwieght balun with just two 4-foot pieces of coax. I would
certainly like someone to try that and let us know how well it works.

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
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Graphics by Loek Frederiks

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

Well, your design certainly started me thinking. So, I began winding...
on a single core--of course...

I am NOT claiming this is unique, but it works better than the design
you presented, at least, ON my sw receiver...

... take a look at it he
http://blake.prohosting.com/mailguy2/balun2.JPG

Warmest regards,
John


"Chris Trask" wrote in message
link.net...
Tom is absolutely desparate to prove to the world that you cannot
under
any circumstances make a 4:1 current balun on a single core. So, he
tests
the single core Guanella balun with the usual test for a current balun
(short the outputs to gound one at a time and see if the input return
loss
changes) knowing fully well that the Guanella 4:1 current balun on a
single
core will only work with floating loads.

He is now equally desparate to prove that since nobody but he
understands transmission line transformers it is impossible for anyone
else
to understand or apply them. He also fails completely in
understanding that
the ferrite used in transmission line transformers is to improve the
low
frequency end by making the transmission line appear longer.

He's truly amazing, and he is mad as hell. He claims that it is
absolutely impossible to make a 4:1 current balun on a single core
with a
pair of 1:1 transformers (of any kind whatsoever), while the Guanelle
4:1
current balun has a pair of 1:1 transformers on a single core right in
front
of him. He also makes numerous other outrageous claims that defy all
manner
of electronics theory.

Here are some of his more memorable quotes along with the URLs for
the
QRP-L archives so you can see that he is not taken out of context,
contrary
to what he says:

"...it is impossible to build a 4:1 ratio current balun that
uses two 1:1 baluns on a single core."

which in the archives at:

http://mailman.qth.net/pipermail/qrp...12/020884.html

This is a good one:

"It's well established any balun made up of series / parallel
transmission lines requires different voltages from the start
to finish of each transmission line. "

which in the archives at:

http://mailman.qth.net/pipermail/qrp...21/021331.html

and the following:

"It is physically impossible to build a transmission line
current balun other than 1:1 on a single core when the
windings have mutual coupling through the core."

which is in the archives at:

http://mailman.qth.net/pipermail/qrp...22/021442.html

as well as:

"It's well established any balun made up of series / parallel
transmission lines requires different voltages from the
start to finish of each transmission line. You can find it
in voltage maps of the balun."

which is the archives at:

http://mailman.qth.net/pipermail/qrp...21/021331.html

and additionally:

"It is quite possible to build any reasonable ratio of
conventional transformer (as long as it is the square of
turns ratio) on a single core. It is quite impossible to
build a current balun of any ratio other than 1:1 using
multiple transmission line transformers on a single core
unless flux leakage between transmission lines is terrible."

which is in the archives at:

http://mailman.qth.net/pipermail/qrp...22/021408.html

as well as:

"It impossible to build anything but a 1:1 ratio current
balun when multiple transmission line transformers are
placed on a single core. The voltage map shows that, as does
the basic electrical rule of current baluns that all
currents in all windings must sum to zero under all load
balance conditions."

which is in the archives at:

http://mailman.qth.net/pipermail/qrp...22/021416.html

There is no room for ambiguity here. As you can see, he is making
unsubstantiated claims of "it is impossible" and "it is well
established"
that have no basis in fact. The problem here is really that I solved
the
problem of the single-core 4:1 current balun and he is mad as hell
because
in his world such a thing cannot possibly exist. So, he makes up
additional
new electronics theories to prove that everything you 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

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

You do not agree with any of his analysis?

You do not think this is more of an isolation transformer than a
balun?
If not, how do you claim a "transmission line" quality/effect to it?

And, you did notice an insertion loss from this "device", didn't you?

John

"Chris Trask" wrote in message
ink.net...
Be sure to print it out as it changes almost daily. Very
strange,
indeed.

--
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
...
A very interesting analysis of this design can be found at:
http://www.w8ji.com/balun_single_core_41_analysis.htm

... for those who have not yet seen it.

John

"Chris Trask" wrote in message
ink.net...
In recent days on the QRP-L mailing list, the following
remarks
were
made by Tom Rauch, W8JI regarding the design of 4:1 current
baluns:

"...it is impossible to build a 4:1 ratio current balun that
uses two 1:1 baluns on a single core."

and:

"It's well established any balun made up of series / parallel
transmission lines requires different voltages from the start
to finish of each transmission line. "

I have devised and modeled a 4:1 current balun using two 1:1
baluns
on
a
single core, and have tested a fully functional prototype. The
design
can
be built without any core, if so desired. The full disclosure
of
this
design with all theory, references, and test results can be
obtained
from my
web page at:

http://www.home.earthlink.net/~chris...k4to1Balun.pdf

The design proves beyond all reasonable doubt that the above
statements to
the contrary are, to put it mildly, gravely in error.

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