[TowerTalk] Lunar Dipole

[Dan Maguire]

On 1/3/2020 10:21 AM, Jim Lux wrote:
>>> FWIW, this is calculating the input impedance of a 900 m dipole 1mm in diameter near the surface of the moon, 3+0.00503j [edit: minus, not plus?] is the complex permittivity of Lunar regolith

>>> GN 3 0 0 0 3.000000 -0.005030

>>> https://www.colorado.edu/project/lunar-farside/

Well golly, doing the calculations for a low dipole on the surface of
the moon sounds like it's just too much fun to pass up.  Here's an
animation of the elevation patterns from 0.011 to 0.015 MHz with the
complex dielectric constant (permittivity) held constant at
3.00-j5.03E-3.  In the lower-right corner of each frame, variable "S"
is the ground conductivity in nS/m required to get the desired
permittivity and variable "G" is the gain in dBi at 90° elevation (0°
theta).  The outer ring of the polar plot is fixed at -14.24 dBi, the
gain at 0.015 MHz.

https://i.postimg.cc/tC1p4Dbk/Lunar-Dipole-Pattern.gif

And here are the feedpoint impedances at each frequency.

https://i.postimg.cc/13Gx8jjG/Lunar-Dipole-Rand-X.gif

So if you ever want to set up a remote station on the moon for some
nice DX in the 20000m band this should get you started.  :)

Dan, AC6LA