I am planning to build a triangular 3-element 80-meter vertical phased
array this spring and have been doing a lot of reading on the subject
(primarily the TT archives and ON4UN's book). The elements will be on a 4/5
acre lot adjacent to our residence (I just could not fit a four-square in
the lot and honor setbacks from the road required by our county).
One remaining question is how to do the radials. I am planning 60
1/4-wavelength radials for each element (this will not be done perfectly in
all directions because of lot lines, but I see that as ignorable). I intend
to just tack the radials to the ground or to use the K1VR "sewing method"
that I found in the achieves to get under some of the brush that was not
there 20 years ago.
I have been looking at figure 11-99 of ON4UN's book, where he shows bus
wires emanating from a point at the center of the element locations, with
the radial spokes terminating at the bus wire. It is not clear if this
method is designed to save wire or to provide some kind of optimum radial
system.
For two reasons, I would prefer to use insulated wire and cut all of the
radials to 1/4 wavelength, and let them cross.
1. It is easier and less time consuming
2. I am worried about the long-term reliability of the bonds to the bus
wire (which also makes me wonder if the DC connection is important, if the
radials are wrapped around the bus wire sufficiently to have a good
mechanical connection).
There was some discussion of crossing radials in the achieves, but nothing
conclusive. Someone, at that time, suggested crossing radials could cause
problems because of interactions in currents flowing in the radials and
that it might be modeled, but that type of modeling is beyond my current
abilities.
One other thing is that there are a substantial number of radials from my
existing HF2V vertical (in a different part of the field) that would lead
to some crossing radials. It would be difficult, but not impossible to get
them all up, but is there any reason to do so (as I would prefer to leave
the HF2V operational, if for no other reason, than to provide a
comparison)? Most of the old radials came from insulated scrap wire,
accumulated over they years.
73, Bill
K0KT
William Q. Meeker
Department of Statistics
304C Snedecor Hall
Iowa State University
Ames, Iowa 50011
Phone: 515-294-5336
Fax: 515-294-4040
Home Fax: 515-232-1323
www.public.iastate.edu/~wqmeeker
_______________________________________________
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Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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