One important detail, if I am not wrong:You need more than a quarter wave
parasitic elements. Otherwise, you'll be doing a parasitic element for around
3,6 MHz.It must be half wavelength minus 4% - 5% lenght for a director element.
Or: You install a near quarter wave element with radials or just one radial in
the direction you want to enhance your antenna system.Resonate it at a higher
frequency (4 - 5 %), while having your existing vertical open to detune it so
it does not affect the parasitic tuning.Then retune your vertical if needed,
with the parasitic installed and closed (radial(s) and vertical or sloping
element connected).
73
David
HK1A
EC5KXA
ex-HK1KXA
> Date: Mon, 2 Aug 2010 22:16:07 -0700
> From: tree@kkn.net
> To: ljdoyle@suscom-maine.net
> CC: Topband@contesting.com
> Subject: Re: Topband: parasitic element
>
> On Mon, Aug 02, 2010 at 12:11:17PM -0400, John wrote:
>
> > tq all the antenna guru's, been thinking of adding a parasitic element to
> > my existing 135 quarter wave vertical to give me a little more gain to the
> > NW my question would it work?the the quarter wave wire would be insulated
> > from the top of the tower and sloping toward the NW and another insulator
> > at the far sloping end and anchored to a tree...appreciate anyone's
> > opinion..John K1GUN
>
> Well - yes - it can help. You can probably get a bit of gain - but maybe
> more importantly - get some front/back.
>
> One limitation is that you will only get it over a pretty narrow frequency
> range (30 kHz or so).
>
> Tree N6TR
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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