Go to yahoo.com, do a search on '10m wonder bar antenna' and see what you
Maybe between the number of the 17m and the 10m wonder bars, you can
extrapolate numbers for other bands.
> -----Original Message-----
> From: firstname.lastname@example.org
> [mailto:email@example.com] On Behalf Of Doug
> Sent: Wednesday, December 20, 2006 10:01 AM
> To: firstname.lastname@example.org
> Subject: [TowerTalk] 17M Wonder Bar Antenna
> In reading the Jan 2007 issue of 'QST' I came across the
> article, "17 Meter Wonder Bar Antenna". This antenna appeals
> to me due to the fact of low wind resistance, the ability to
> use a TV rotor to turn it, and I have all the materials for
> construction. However, the article left me with a number of
> 1. No formulae were given to scale the antenna up or down to
> suit other bands. I have built a number of yagi antennas and
> I generally understand how to formulate changes for given
> bands. However, this antenna has shortened elements, in a
> bow-tie configuration, and therefore I do not have a clue how
> to figure the boom spacing of the elements, size of the
> elements, or the coil size required. I would like to
> understand how to compute dimensions for shortened element antennas.
> 2. This particular antenna uses coils wound on 1" ID PVC.
> Would an air wound coil be more efficient or have an
> advantage over this design?
> 3. The author capacitive couples the feed line to the coil
> of the driven element. Is there a more efficient or solid
> means of connection? Would anyone have a guess as to the
> power handling capability of such a setup?
> 4. Tuning the coils to make the elements resonant left me a
> little fuzzy. If I construct the coil / element assembly how
> do I properly attach my MFJ-259 (Pre B Version with only the
> PL-259 connection) to the coil? Does a reading of the lowest
> SWR actually indicate resonance? I also have a grid dip
> meter if this would provide a more useful measurement of resonance.
> I fully understand that this antenna is not the most
> efficient design that I could use. However, for the reasons
> stated above, it definitely would work well in my location.
> This will all become a moot point when my 80' tower is
> erected, but until such time, this should provide me with a
> decent antenna at little or no cost.
> Thanks for your assistance,
> Doug Coffman - N9XTF
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