I am considering constructing an array for 40m made of two quarter-wave
verticals spaced an eighth wavelength apart using a Christman feed
method. The details of this array are discussed in ON4UN's Low Band
DXing pages 11-34 and 11-35 (third edition). The picture of the array,
however, (page 11-35, figure 11-39) shows the two verticals without
radials. In the same chapter, John shows several other vertical array
diagrams, some of which include radials in the drawing, but I can't tell
if this array requires radials as well. I have read the text, but no
mention of radials their either. I would imagine that this array would
require at least 2 quarter-wave verticals on each vertical, correct? And
if not, what would I do with the shield of the coax?
Also, on a related topic, is it possible to make arrays such as this
using different types of wire? In other words, I have a G5RV as well as
an Alpha Delta 80m dipole that I am not using that I could cut up to
make the verticals. If the array requires radials, however, I would need
to use wire from both antennas and the wire types used in the G5RV and
dipole are not the same. Would this affect the performance of the
antenna in any way, or is it just the measurements of the wire and not
the type of wire used that matters?
73, Nat, WZ3AR
<nat@ajheatwole.com>
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