On Sep 14, 12:22*pm, "Frank" wrote:
These were shore based installations probably in Hawaii or some
island.
With respect to resonance, moving away from such as well as changing
from 15 degrees
(Frank's 30 degrees divided by two)
would provide a pattern of distinct advantage which the navy is
constantly looking for
For a whip tipped at an angle of 15 degrees can provide a forward
pattern of gain which can be a big deal
I anticipate that the navy will gyrate towards helical design where
the addition of a magnetic field will give a pattern of choice
together with resonance the size of a shoebox to reduce the number of
antennas on board.
Thanks for the info, it certainly was not silly As an aside the 15
degrees is the same as found empirically by Kraus
in the pitch angle of a helical, another example of the inclusion of
the weak force in a system in equilibrium !

My original model was for a dipole tilted 45 degrees. *The following
analysis is for a 35 ft ground mounted monopole with thirty-six 40 ft
radials buried 1" below an average ground of: conductivity 5 mS/m,
and relative permittivity 13. *It is noted that the tilted monopole has
a slight gain opposite to the direction of tilt. *The following comparison
is made in the direction of maximum gain. *The F/B ratio is nominally
0.2 db, and the gain 0.2 db at lower angles. *The measurement was
made on 7.2 MHz, and the input impedance 45 + j 47 ohms.

Take off Angle * * * *Vertical * * * * * *15 deg tilt
(degrees) * * * * * * * Gain (dbi) * * * * * Gain (dbi)
10 * * * * * * * * * * * * * *-2.5 * * * * * * * * * *-2.3
20 * * * * * * * * * * * * * *-0.2 * * * * * * * * * *0
30 * * * * * * * * * * * * * * *0 * * * * * * * * * * * +0.3
40 * * * * * * * * * * * * * * -0.8 * * * * * * * * *-0.3
50 * * * * * * * * * * * * * *-2.3 * * * * * * * * * -1.5
60 * * * * * * * * * * * * * *-4.6 * * * * * * * * * -3.3
70 * * * * * * * * * * * * * *-8.0 * * * * * * * * * -5.9
80 * * * * * * * * * * * * * -14.0 * * * * * * * * *-9.3
90 * * * * * * * * * *Deep null * * * * * * * * * -13.4

CM Monopole with buried radial system.
CE
GW 1 1 0 0 0 0 1 -0.083 0.0026708
GW 37 39 0 1 -0.083 0 40 -0.083 0.0026708
GR 1 36
GS 0 0 0.304800
GE -1 -1 0
GN 2 0 0 0 13.0000 0.0050
FR 0 1 0 0 7.2 0.01
LD 5 0 0 0 5.8001E7
WG monopole_36.NGF
EN

CM 36 Radial Read NGF
CE
GF 0 monopole_36.NGF
GW 73 35 0 9.0587 33.807 0 0 0 0.002671
GS 0 0 0.304800
GE 0 0 0
EX 0 73 35 0 6349.474358 0.00000
LD 5 0 0 0 5.8001E7
RP 0 181 1 1000 -90 270 1.00000 1.00000
EN

73, *Frank

Frank I am not familiar with your programming but the weak force is
just that....weak
It is for that reason the Yagi coupling of elements provides a good
estimate with easy structure.
For long distance accurracy is not a big deal but for measuring and
for medical applications it is.
Art