I would assemble it and check where the "dip" is in SWR. This is the only
real world measurement any antenna tech can make. Be sure to raise the
assembled array as high as you can and measure where the dip is. Ground
measurements should be made at least 2 wavelengths away from other
obstacles.
73
Doug
WB1E
On Fri, Jan 27, 2023 at 5:42 AM Art Greenberg <art@artg.tv> wrote:
> The antenna is a 6 element 6m yagi, VB-66DX. The instructions are a
> photocopy of a photocopy, I think. The drawing is too small to see
> sufficient detail.
>
> I have an earlier version of this antenna, the 6m "Long John", and for
> that the elements were indeed pre-cut. There was only a little room for
> adjustment, that being the depth into the element bracket that the
> element was inserted.
>
> This antenna has a short section of 7/16 dia. tubing at the boom end of
> each element, and the 7/16 dia. tubing telescopes into that. That change
> provides much more room for adjustment. I presume the change also
> lengthens the life of the elements.
>
>
> On 1/26/23 23:00, Jim W7RY wrote:
> > Most hygain antennas use a predetermined length of tubing at each
> > element. The measurements are usually just for the joints after the
> > first piece of aluminum that is hooked to the boom.
> >
> > But, this TH-6 diagram shows the lengths of the pieces against the boom.
> >
> > What do the instructions show?
> >
> >
> > 73, Jim W7RY
> >
> >
> >
> > On 1/26/2023 4:26 PM, Art Greenberg wrote:
> >> I should proof read before posting. The DE is insulated from the boom.
> >> Fed with a beta match. Its a Hy-Gain antenna.
> >>
> >>
> >> On 1/26/23 17:24, Art Greenberg wrote:
> >>> I think I left out an important detail. Elements are all connected to
> >>> the boom. Even the DE, fed with a "beta" match.
> >>>
> >>>
> >>> On 1/26/23 17:22, Doug Christensen wrote:
> >>>> From center of where the electrical connection starts near the
> >>>> boom, to
> >>>> where the element terminates at the outside of the array.
> >>>>
> >>>> doug
> >>>> wb1e
> >>>> 73
> >>>>
> >>>> On Thu, Jan 26, 2023, 12:34 PM Art Greenberg <art@artg.tv> wrote:
> >>>>
> >>>>> The instructions for setting element length aren't clear. Do I
> measure
> >>>>> from element tip to the side of the boom, or to the center of the
> >>>>> boom?
> >>>>>
> >>>>> I think its the later ...
> >>>>>
> >>>>> TNX
> >>>>>
> >>>>> --
> >>>>> Art Greenberg
> >>>>> WA2LLN
> >>>>> art@artg.tv
> >>>>> _______________________________________________
> >>>>>
> >>>>>
> >>>>>
> >>>>> _______________________________________________
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> >>>>>
> >>>> _______________________________________________
> >>>>
> >>>>
> >>>>
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> >>>
> >>
> >
>
> --
> Art Greenberg
> art@artg.tv
> _______________________________________________
>
>
>
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