Jeffrey Yeager wrote:
>
> Getting ready to stack 2 TH-6s.
> Am planning on have 2 identical lengths of RG-213 going from each TH6,
> to a stack match. What is the best way to connect the coax to the TH-6s???
> I have 1 hygain balun and a balun of unkown history. Have heard some use
> ferritte beads on the coax (values unknown) Any specific solutions that
> work?????
>
> 73 Jeff KQ4HC
> jnyeager@southern.edu
>
>
Jeff nice to know the Stack Match is becoming a houshold term. I
monitor this reflector and anyone with Stack Match, or Dunestar
questions is welcome to pop us a line for advice or Give Advice for that
matter.
You can also find us as http://www.dunestar.com
Now to your question. Don't spend all that money and use unknown
baluns.
You must know exactly what the polarity of the balun is. Other wise you
will have an out of phase situation or slightly out of phase situation.
Either way you lose. I would either get another matching Hygain Balun
or make your own.
I actuall preferre the make your own balun better. Do not use ferrite
beads. To work these bead must be of 2500 u permeability to keep the
stack of them short enouph to be under a foot long. But you sacrifice
efficiency into heat.
I have got them so hot that a balun made by a well know manufacturer
caught on fire at the first bead. Many others have had the same
experience.
Use a 125u Torroid 2.4 inches in diameter and get some RG142 coax. Wrap
the coax around it 7-10 times and terminate one end with a Pl259 and the
other with two wires to go to the beam.
I put them in a 2x2x4 inch Hubble grey box, sold at home depot. You can
then mount an SO 239 connector on one side of the box. It comes with a
rubber wx seal. drill two holes on either side and push the wires
through. Attatch these to the feed point. Voila a better balun than
you can buy at 5X the cost. And you know the polarityh of it. Just
hook them up the same on each yagi.
Good luck with the stack, it'll play real well. Lots of guys use them.
What will the stacking distance be BTW. 32 feet is good compromise for
all bands. But you should model it for your tower on all 3 bands to get
a feel for the pattern you want.
73 Jay WX0B
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