Thread: Homebrew tuners
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Old July 30th 03, 02:09 PM
Art Unwin KB9MZ
 
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Yes George, I mispoke, you are correct
It says in very large letters on it " TRANSFORMER"
Since transformers are touted as being efficient
I was wondering how it would compare with
the normal tuner. Half of the challenge for me
was to come up with an inexpensive switching
system where the input was stationary while the rest
were switched thru and then repeated for the next
input e.t.c. With that being solved I look forward
to finishing and then playing with it
Regards
Art



"George, W5YR" wrote in message ...
Art, are you sure you have a balun? Your description sounds like a tapped
r-f transformer.

A balun, of course, is completely different from a transformer in that it is
a "transmission line transformer" which is made of short transmission line
sections instead of "windings."

If a balun is made with line sections of Zo, then the load must be an
appropriate multiple of Zo and purely resistive for the balun to function
properly.

Usually it is best to let a balun do the current steering and keep the outer
braid of the coax "clean" and do the impedance matching elsewhere, as in a
tuner.

Just a thought . . .

--
73/72, George
Amateur Radio W5YR - the Yellow Rose of Texas
Fairview, TX 30 mi NE of Dallas in Collin county EM13QE
"In the 57th year and it just keeps getting better!"






"Art Unwin KB9MZ" wrote in message
m...
Seems like a lot of hams with limited resources are still compelled
to operate on many bands with just a long wire and a tuner.
The wire is inexpensive but the tuners are not. Thus my present
project.
I was given a Palomar enginnering balun with 5 female connenection
which by selection can match a antenna in steps from 5 ohms to over
450 ohms
in a series of steps. I am presently rigging it up so that all
steps can be switched thru remotely by a single motor. The switching
arrangement
is the main challenge since inexpensive means simple.
Now I have not measured losses of the balun before hand because the
switching
challenge is what is driving me.
Anybody have any thoughts about what I should expect from this
balun other than knowing that it is not a tuner as is generally known
since
it does not have the ability to obtain the priceless 1:1 condition
that so many desire?
Regards
Art