Reg Edwards wrote:
"Tim Wescott" wrote in message
...
Reg Edwards wrote:
Why use a balanced tuner when a less expensive, easier to operate,
unbalanced tuner, in conjunction with a simple choke-balun, will
do
just as well?
Insert the 2-wire choke-balun between the unbalanced tuner and the
balanced transmission line.
----
Reg.
Because a balun particularly lossy at high SWR -- with a balanced
tuner
followed by a balun you present the balun with the correct
impedance, so
it's at its best.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
========================================
Tim!
I don't know what design services you offer but you are WRONG.
You must have been reading the wrong comical magazines.
A choke balun is amongst the most power-efficient devices.
It consists only of a pair of wires wound around a ferrite ring. It is
just a very short transmission line of the same length as the wire and
has the same very low loss.
It has a phase shift of the same length of line. Which is immaterial
insofar as the tuner is concerned. It merely changes the tuner L and
C settings.
----
Reg.
Sorry. I thought you were asking for help. My mistake.
Odd that you should answer the question when you already know the
answer, though.
To answer you unasked question: No, I do not have any test results, so
you are correct that I am just repeating the absorbed wisdom of others.
I'll be sure to qualify any similar answers I give in the future.
Until I get an HF system up again I won't be doing any measurements, so
don't hold your breath.
To ask you the same question: would you please post _your_ test results?
Pontificating from first principals is what you do if you are engaged in
preliminary design or the unpaid answering of questions.
Sticking to your guns in such cases is tilting over to philosophy,
religion, incompetence or internet trolling.
But you are sure enough of yourself to use capital letters when telling
me I was mistaken, so you cannot possibly be incompetent or a spinner of
trolls.
So I am confident that you are working from real, measured data, not
just derived results based on calculations or reasoning from first
principals. At most you are once removed from some reliable individual
or group who has done the measurements. It is very ungenerous of you
not to share a properly detailed report on your experiments, or a
reference to the report of the folks who did do the work -- a link to a
page will do, or even a reference to a periodical or book should the
information not be available on the web.
I'm ready to change my thinking just as soon as I see something
credible, and quite interested in the results because I don't see the
point in building a balanced tuner if my existing unbalanced one will do.
Thanks.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com