[TowerTalk] passive "autotuner"?????

doc kd4e at verizon.net
Thu Jun 8 14:42:40 EDT 2006

 > discom101 at sohostar.net wrote:
> my first thoughts on how to do the automatic "selection" is to use series
> resonant circuits in series with the parallel resonant circuits. the
> simplest way to test it is to use 1/4w stubs. a shorted stub behaves like a
> parallel resonant circuit, and an open stub like a series resonant circuit.
> the advantage of using stubs is that they behave that way at more than one
> freq, and will lessen the "parts count". at least if it doesn't work, i'll
> find out why. i'll also be able to share my results with the group. who
> knows, somebody might come up with a better way to do it?

Is this what you are proposing?

It would present a mostly horizontal component with the stubs
serving as a small vertical component.

The stubs might just hang and be flexibly tensioned to prevent
tangling in the wind, or perhaps attached to the sides of a
non-conductive vertical center support like thick-wall PVC.

I have no idea if this would work!  :-)

                           |              |
Left side of folded dipole ------  ------ right side of folded dipole
                                 *  *
                             )!|${  {$|!)  These represent pairs of stubs
                             )!|${  {$|!)  for each of 5 bands in series
                             )!|${  {$|!)  with each side of the folded
                             )!|${  {$|!)  dipole inserted between each
                             )!|${  {$|!)  side of the lower half of the
                             )!|${  {$|!)  dipole and the feedline.  The
                             )!|$    $|!)  theory being that the signal
                             )!|      |!)  selects the most resonant path
                             )!        !)  and ignores the rest.
                             )          )

Thanks! & 73, doc kd4e  http://bibleseven.com
Florida Home w/Rohn 45 in concrete base & 10 acres for sale:

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