Antennas requiring ground planes are called ground plane dependent and having an appropriate ground plane can greatly affect performance.
Ham station sheet metal ground plane.
Sometimes we set ourselves up for problems without knowing it.
A ground plane is a reflective metal surface that the signal from an antenna bounces off of to better meet the antenna s design goals.
What are the ground counterpoise alternatives to driving an 8 foot metal pole into the ground.
A cookie or pizza sheet works fine as a ground plane for a 70cm or even 2m vertical but it s a very small ground plane on 10m or lower bands.
I live in an apartment and i highly doubt i can do this.
3 the problem is not rf at all but is a dc power supply ground loop back into the audio system.
As the name indicates the antenna ground plane acts as a simulated ground.
4 equipment has a design defect.
The ground stake near the house provides a place for the common mode noise current to go far from the antenna where it cannot couple significantly.
That s only 05 wavelengths at 30 mhz which is a tiny ground plane.
I guess what i m simply not clear on is how a mag mount antenna s ground plane is connected electrically.
Connection to other conductors just under the surface like a metal water pipe is next.
Both of these should result in some level of electrical isolation between the antenna feed shield and the sheet metal.
Consider also that most cars have a coat of paint between the mag mount and the sheet metal.
It is possible to simulate this function by replacing the real earth.
A dependent antenna can become effectively useless without one.
Shallow buried radial wires are the best.
The ground stake at the base of my inverted l antenna provides a place for the antenna current to flow at a true ground potential relative to the antenna potential.
The individual station equipments already have their own ground reference but when they are interconnected grounding each equipment to the main ground bus as shown in fig 1 creates ground loops.
These are for the rf ground described above.
Each time a ground loop is created a small inductive coil is formed the ground wire completes the loop.
It is found that for a monopole antenna like a quarter wavelength vertical the ground acts as a plane to reflect the radio waves so that an image of the top half of the antenna is seen in the earth.
A very large pizza sheet might be around a meter in diameter or iow 50cm in radius.
Dx engineering radio rf ground plane kits provide an effective method of reducing stray rf pickup by equipment and interconnecting cables.
