Some of you have asked for more of the details on the phased verticals
so here it is.
I have a four in line vertical array for 80 meters that have been
constructed but not matched and phased yet. The verticals are .25
wavelength long and the seperation is .25 wavelength. Each has 50 .25
wavelength radials.
The self impedances measured (which are the impedance of each vertical
with the other ones open) are: Bridge is the General Radio 1606A.
Figures below are corrected to be right at the base of each insulated
vertical
Vertical 1 28.2 + j2.5
Vertical 2 28.1 + j1.2
Vertical 3 30.6 + j 4.8
Vertical 4 29.8 + j 2.5
Currents and Phase angle designed for:
Vertical 1 1 amp @ 0 degrees
Vertical 2 3 amps @ -116 degrees
Vertical 3 3 amps @ -232 degrees
Vertical 4 1 amps @ -348 degrees.
Coupled Impedance measured between verticals. ie on Z 1-2 measurement
is taken at vertical 1 with vertical 2 shorted and the others open.
Impedance are right at the base of the insulated vertical.
Z12 38.2 + j7.2
Z21 37.7 +j8.0
Z13 23.6 -j0
Z31 24.6 +j2.5
Z14 31.8 +j3.9
Z41 33.7 +j1.8
Z23 37.2 +j8.8
Z32 39.0 +j11.3
Z24 23.6 +j0.8
Z42 25.2 -j4.6
Z34 40.2 +j9.6
Z43 42.7 +j4.8
Calculated Mutual Impedance are:( ie this is the average of Z12 and Z21)
Z12 4 -j17
Z13 -13 -j4
Z14 -2 +j10
Z23 6 -j17
Z24 -12 -j4
Z34 4-j17
The Driving point Z was calculated using the above currents and phases,
the Mutual impedances, and the self Z which was taken as 28.5 +j 2.5
Vertical 1 6.5 - j0.0
Vertical 2 17.5 + j5.7
Vertical 3 36.6 + j21.8
Vertical 4 80.4 + 81.5
I have seen numbers for a 3 in line array but no field values for a 4 in
line array. I was wondering if any one has built and
measured/calculated the Driving point Z so I could see if I am in the
ball park.
Denis Ve6AQ / VE6FI
|