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Old August 23rd 05, 09:35 PM
Fred W4JLE
 
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At some point a resonance will occur Reg. And while some particular
combination may work - i.e. 7,427 ferrite beads along 841 feet of coax. I
have found no practical balun that does the deed from 1.8 to 30.

Those that work well at 1.8 seem to end up with a resonance somewhere over
20 Mhz..

One solution may be ferrites to cover the low end in series with a solenoid
coil for the high end.

Again, what I am looking for is a simple chart that says for a 10, 15, and
20 meter beam a solenoid of 8 turns on a 4 1/2" pvc coil form will provide
the following impedances ...

Also most people will tell you that just looping the coils together will
cause problems because of capacitance. I don't see that as a bad thing.
Again I need to see data to confirm or discount my assumptions.

If nothing else it will be a fun learning exercise.

I ran into some problems with an all band no tuner antenna and started to
try various combinations of beads recommended by the Gurus. While it worked
OK on 160, 75 and 40, at 15 and10 meters the beads has insufficient
impedance.

Ergo, I have mounted my steed and wooden lance in hand am off to fight the
evil forces of unbalance.

"Reg Edwards" wrote in message
...
The only things I know for sure is that no balun covers from DC to

daylight,
or even 1.8 to 30 Mhz.

==============================
Fred, I'm afraid you're wrong.

Slide a sufficient number of ferrite beads over the coax line and it
will easily cover 1.8 to 30 MHz. Alternatively, wind sufficient turns
around a largish ferrite ring of the correct grade of material.
----
Reg.