We are using the term "ground plane" inappropriately in our TMCC/Legacy discussions. A ground plane is a large conductive area at zero volts reference potential. In our case, the earth-ground leg of our signal transmission signal is neither one of these.
Our ground plane is not "large" in relation to the wavelength of our radio signals, which have wavelengths that are .4 miles long.
Our ground plane is not at zero volts reference potential. In fact, the earth-ground leg of our signal transmission system is the PRIMARY RADIATOR of the airborne radio waves received by our locomotives. If you had to choose a "zero volts reference", you would be much more accurate to pick the outer rails of the track. This is the conductive surface that is connected to the frame of the locomotive and the ground side of the radio receiver inside the locomotive (and the negative side of the regulated power supply inside the locomotive.)
Here are some suggestions for a new more descriptive term:
Supplementary radiator
Added or additional radiator
Extra radiator
Ground signal radiator
I think the term should include "radiator" to help people understand that there is a signal coming off of this conductor.
How do you vote? Any other suggestions?
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