I concur, suggesting various options and/or links to how things work is not
a bad thing! The original post stated that he was unable to install 60 33ft
radial and it was pointed out by several (including me) that this is not
necessary for the vertical to work reasonably well. On 80m this antenna uses
a base coil which is the least efficient loading method, even a perfect
radial field wont help that. AF7WH is probably using a SteppIR BigIR to
satisfy his HOA. All antenna systems are compromises and we do the best
that we can with whatever space, financial and legal restrictions we may
have.
John KK9A
Mike Fatchett W0MU wrote:
We simply pointed out that he did not have to use raised radials. That
is all. The OP is free to do what he wants. The value of the list is
to propose alternatives that might be easier for the OP.
W0MU
On 10/27/2025 7:08 AM, Mike Smith VE9AA wrote:
> Dale,
>
> Short answer: I have almost the exact same setup. It'll work.
>
> How nearly half the readership got onto ground radials and arguing I am
not
> certain. It does kinda seem that a number of threads on Towertalk and
> CQ-Contest fly off the rails fairly quickly often involving adjacent
> discussions for reasons that I cannot fathom. You asked a pretty
> straightforward question and I hope the answer below will help you.
>
> My example is an HF9V multiband vertical mounted on the back of my shed
(on
> a side where a gutter would normally be, not on the peak) around the 6.5'
> mark AGL.
>
> I then made 2 RESONANT (raised) radials for each band I intended to
operate
> from. 80, 40,30, 20, 15*, 17, 12 and 10m.
> I skipped 6m radials as I use yagis on 6m and I skipped the *15m radials
as
> I figured the 40m radials would perform double duty at 3 wavelengths on
15m
> (seems to work).
>
> In my case the RAISED (resonant) radials were first made as a kind of
dipole
> then I got my analyzer out, got them in the ballpark after trimming and
then
> removed the temp. center insulator and attached the pair to the baseplate
of
> the RAISED HF9V.
>
> I have 2 raised resonant radials extending out roughly 180* apart from one
> attachment point for each band, running in the air and over branches in
fir
> trees and ultimately tied off to the tops of 50yr old cedar fence posts
> around the 4' mark in most cases (so sloped down slightly from the
multiband
> verticals base which is at 6-7' AGL).
>
> The RAISED (resonant) radials start out together and then I fan them
out
> as well as could be expected but most of them are 6"-12" apart from one
> another using air or in some cases super small PVC spacers.(spacing varies
a
> lot)
>
> I was able to obtain a near perfect SWR on most bands and operation of the
> HF9V mounted 6-7' AGL is as to be expected. (some would say radiates
poorly
> in all directions, hi)
>
> Over the years some of the radials have sagged or fallen (tree branches!)
> and I have caught the odd one or two with a tractor or a ladder or some
deer
> (buck) caught his antlers or whatever and some of them have become
slightly
> tangled (storms) and I do some half hearted repairs but have never noticed
> much degradation in Signal strengths or SWR measurements. It's only a
> backup to a backup antenna, so almost never gets used these days. My wire
> 4-squares are always better (and quieter) so the HF9V, while solid, plays
> 3rd fiddle now.
>
> Once you do your first "dipole" or two of some of the RAISED (resonant)
> radials you can do the math and make subsequent radial pairs with little
or
> no antenna analyzer measurements needed imo. Bend them, it matters very
> little.
>
> GL with it!
>
> Mike - VE9Antenna Antenna
>
> AF7WH asks:
>
>
> I have a SteppIR BigIR vertical that I am refurbishing. It will be
> installed
> in a small backyard that does not allow for the normal ground radial
system
> (such as 60 ea at 33'). I will need to go to 2 ea tuned elevated radials
> for
> each band (80 thru 10 - 8 bands). My solution (I think the only one I
have
> due
> to lot restrictions) is to run the radials along the vinyl fence. The
> vertical
> is mounted on a 4x4 post at 5 feet above the ground. One direction has
> about
> 70' of length (straight) but the other direction has a 90-degree turn
about
> 20
> feet down from the antenna and then a straight shot the rest of the
lengths
> so
> the radials for 80, 40, and 30 will have a 90-degree bend at that point
and
> then continue on straight. All the radials will follow the fence line so
> they
> will not be spaced out is a circular distribution from the antenna. There
> will
> be about 1 to 2 feet of horizonal spacing in the plane for 4 bands (80,
40,
> 30
> and 20). I will do a similar install for the 17, 15, 12
> and 10m bands but will have them be 1 to 2 feet down vertically from
the
> 1st
> set of radials. Hopefully, this is clear and not confusing - I do not
think
> I
> am able to post a diagram of what I want to try.
>
> Couple of questions:
>
> Will this work?
>
> What is the minimum spacing horizontally and vertically for the radials as
> proposed?
>
> Any other suggestions?
>
> Thanks,
> Dale
> AF7WH
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