Near broken guys - No problem
My 80M 4-SQ have been around two different tower , each with varied guying.
One even had no insulators on the bottom guy.
On Tue, Nov 17, 2020 at 8:50 PM <kq2m@kq2m.com> wrote:
> Hi,
>
> I want to thank K0PJ/9, W9PL, AC0C, W6RMK, W7VJ and VE9AA for your
> willingness to help and all the valuable information and insight!
> Sorry for the delay in my response but I have been working day and night
> professionally and in clearing woods, building antennas, etc. The limited
> daylight now is another large factor. ;-)
>
> I have some new questions and would appreciate your insight and help:
>
> 1) In the past I have used 1/4 wavelength ELEVATED radials for my 80 meter
> wire 4-square but AC0C mentioned that it would be beneficial to use radials
> that were NOT 1/4 wavelength. Should the radials be longer? Shorter? By
> how much? I assume that all the ELEVATED radials be the same length
> regardless of what fraction of wavelength is used – is that correct?
>
> 2) An old 4-square has 1/4 wavelength wire elements that have grown into
> the trees. There is no way to get them down but I can cut a small length
> off of them so that they are non-resonant and not attached to anything.
> Will that be okay or is there going to be a problem with them causing
> interaction if these elements are within 1/2 wavelength of the new wire
> 4-square with ELEVATED radials?
>
> 3) The only place the feedpoint of my 160 Inv L can go on my property is
> about 120’ - 130’ from the nearest feedpoints of the wire elements of my 80
> meter 4-square and probably somewhat closer to the elevated radials. Is
> this going to cause a significant interaction problem? I can ensure that
> the elevated radials of the 160 Inv L do not cross those of the elevated
> radials of the 80 Inv L if that would help. Would that help?
>
> 4) The SW element of the 80 meter 4square will be within 5’-10’ feet of
> the guy wires of my 130’ tower from four ropes will support the elements of
> the wire 4-square. The guy wires are broken up into non-resonant lengths
> with insulators as follows starting from the tower 4’, 4’, 4’, 16’, 16’,
> 28’, 28’, 28’. The NW and NE elements will be about 15’ away from the guy
> wires.
>
> Will this be enough to prevent interaction with the tower guys or will the
> 4-square radiation pattern be adversely impacted?
>
> Thanks in advance for your insights and help!
>
> 73
>
> Bob KQ2M
>
>
> -----Original Message-----
> From: Jeff Blaine
> Sent: Saturday, October 31, 2020 4:51 PM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] 4 square question Part III
>
> Bob,
>
> My 2 cents here. There is a practical answer and an ideal answer to the
> "which direction do my radials point."
>
> My answer is that you space them so that they are not overlapping and
> share the maximum separation with respect to the feed & with each
> other. I also choked on both ends of the feed my verts to try to
> contain the elements and the radials as the only intentional radiators.
> Opinions vary as to this need but I'm personally a big believer in
> conductive elements participating in the antenna thing unless you do
> something to prevent that in advance.
>
> On the other hand, unless you specifically measure the actual radials
> and use a length somewhat off of 1/4 wl exactly, then the result is
> almost certainly that one of the radials will hog the current and that
> will bend your pattern on that one vertical.
>
> So one answer is that it does not matter, and the other answer is that
> it matters a lot if you want to peel the onion back another layer and go
> for a more optimized installation. The problem with that is the benefit
> of doing it in a more complicated way is probably lost on most guys
> anyway because the improvements are not determinable in advance. A 4SQ
> is a magical beast that will work "good enough" even with terrible
> compromises and construction - where an optimized one is not really
> appreciated because most hams don't have a way of doing a before/after
> sort of evaluation.
>
> Good luck!
>
> 73/jeff/ac0c
> alpha-charlie-zero-charlie
> www.ac0c.com
>
>
> On 10/31/20 3:31 PM, jimlux wrote:
> > On 10/31/20 12:11 PM, kq2m@kq2m.com wrote:
> >> I want to thank KK9A, NA6O, W4EF, SM2EKM, DCharing (callsign?) and
> >> W6RMK, for all of their guidance, comments and links to helpful
> >> sites. Greatly appreciated as always!
> >>
> >> Now for the final question... let’s say that the “positions” of the
> >> Gauge 12 or 14 THHN wire 4-square elements are N, E, S, and W,
> >> arranged in a box with the sides broadside to NE, SE, SW, and NW and
> >> all the elements will all have either 3 or 4 elevated radials. I
> >> will be using the Comtek ACB4 (80) phasing box fed with each element
> >> fed with 1/4 wavelengths of RG11 foam coax. (It’s the same phasing
> >> box I have been using for the past 25 years).
> >>
> >> Does it matter what directions the radials are pointing for each
> >> element?
> >
> >
> > Not really - what the radial(s) do is provide a return path for the
> > current that "intercepts" the ground - and reduce "ground loss"
> > (independent of the "counterpoise" function).
> >
> > The elements themselves are assumed omni directional. And it's only
> > some some sort of extreme cases (1 radial) that there's a more than
> > trivial effect on the directionality of the radiation pattern of a
> > single element. What changes is the efficiency (i.e. the loss
> > resistance gets lower as the number of radials increases).
> >
> > In the usual 4SQ "current forcing" array with 3/4 wavelength feed
> > lines, the current in the element (which is what radiates) is the
> > right ampliude and phase to form the beam.
> >
> >
> > So let’s say I am using the NE position on the ACB-4 controller, since
> > I am radiating on all 4 elements, does it matter what directions the
> > radials are pointing? Do I want to have the same radial directions
> > with all 4 elements or do I want to spread out the radial directions
> > differently on each element? Since NE is by far the most important
> > direction for me (Europe), do I want to have more radials pointing NE
> > or broadside NE or equally spread out so that the radiation and
> > current return is more uniform? I am not clear on any of this or if
> > it is even important so I would appreciate any guidance that you can
> > provide!
> >>
> >> My understanding is that I want to get the radials at least .05
> >> wavelength above ground so at least 13’ above ground. Is that correct?
> >>
> >> Tnx & 73
> >>
> >>
> >> Bob, KQ2M
> >>
> >>
> >>
> >> -----Original Message-----
> >> From: jimlux
> >> Sent: Friday, October 23, 2020 8:44 AM
> >> To: towertalk@contesting.com
> >> Subject: Re: [TowerTalk] 4 square question
> >>
> >> On 10/22/20 9:45 PM, Michael Tope wrote:
> >>> Bob,
> >>>
> >>> I found this by googling "4 square 8 directions":
> >>>
> >>> https://ncjweb.com/bonus-content/k3lc4squarea.pdf
> >>>
> >>> I think W8JI describes something similar on his website.
> >>>
> >>> 73, Mike W4EF....................
> >>>
> >>>
> >>
> >> and that 4 square handbook from the DF6QV.. He's got all possible boxes
> >> and phasing
> >> http://tm1o.free.fr/4SQ/80m/en_ver_final4-sq_03_04_15.pdf
> >>
> >>
> >>
> >>>
> >>> On 10/22/2020 7:39 PM, kq2m@kq2m.com wrote:
> >>>> I really want to thank Jim, Jeff, Les, Mike, John and Gary for all of
> >>>> their help, answers and ideas to which I have been giving a lot of
> >>>> thought this week. The information gleaned has made me confident of
> >>>> the new design. Unfortunately there is no way to avoid putting the
> >>>> 4-square elements around the tower so I know that interaction effects
> >>>> will likely be noticed. Vicious storms have taken down all the other
> >>>> tall trees that were previously in use to support my 80 meter
> >>>> 4-square.
> >>>>
> >>>> Note to Jim Lux – I am particularly intrigued by your idea of changing
> >>>> the feeding of the elements so that I can radiate broadside from the
> >>>> side of the array rather than on the diagonal since the only trees
> >>>> that I have to support elements happen to be roughly N, E, S and West,
> >>>> which, with the Comtek phasing box, would give me radiation N, E, S
> >>>> and West rather than the desired NE, SE, SW and NW.
> >>>>
> >>>> The Comtek ACB-4 outdoor box uses the NW element in Pos 1 on the
> >>>> outdoor , NE (2), SE (3) and SW in position 4 and arranged as shown in
> >>>> the .pdf:
> >>>>
> >>>> www.static.dxengineering.com/pdf/comtek_4_square_info.pdf
> >>>>
> >>>> Which elements (N, E, S, W) would you put in which positions on the
> >>>> box (so that the 4-square radiates toward the NE instead of East?
> >>>>
> >>>> How is the gain and F/B and F/S compared to the standard pattern that
> >>>> radiates diagonally?
> >>>>
> >>>>
> >>>> Tnx to all & 73!
> >>>>
> >>>> Bob KQ2MTowerTalk mailing list
> >> TowerTalk@contesting.com
> >> http://lists.contesting.com/mailman/listinfo/towertalk
> >> _______________________________________________
> >>
> >>
> >>
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> >
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