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What about common mode currents through the power supply? Is the power lead to the transmitter considered part of the radiating system if it is not RF supressed? Wouldn’t the power supply leads also possibly radiate? Would they be included as part of the transmitting system? And what about tuned ground systems that don’t radiate? You know, a counterpoise RF ground system. Why is it that RF ground radial systems are buried when they work better on the surface of the earth? Buried, ground radials computer modeled appear more lossy. Where does the entire ground system design begin and end in the entire scope of Part 15 rules or do we have to consider other parts of CFR 47 as well? Where does the FCC term “good engineering practice” play into the grounding issues? And since the FCC doesn’t necessarily regulate safety issues anymore, what section of Part 15 deals with the definitive acceptable design of radio station ground systems? In other words, how can an operator of a Part 15 AM radio station, without question, know his installation is “legal” under all circumstances? And will pass inspection “no matter what’? And at what point does the owner of one these stations have the same treatment as shopping centers, car lots and real estate agents from the FCC? Frankly it sounds way too much like NAB/NPR politics to me. But I digress.
We agree that elevated radial ground systems are beyond Part 15 design parameters. We agree the shortest path to ground is the most acceptable. We don’t agree about radiating ground systems.
Some RF ground systems DO NOT radiate. Current must flow in a ground system for it to radiate. In checking ground systems for licensed AM broadcast stations, we measure the inductive current flow in each radial to determine if it is “healthy”. Low or no current flow means it is operating properly. It also means the impedance in the circuit is extremely high in relationship to the radiating portion (antenna) of the system. That is essentially controlled by Ohm’s Law. It is true the antenna system current return is the ground system, however even in AC circuits the neutral side carries no potential until connected to the hot side through the resistive load. Kapish? How does radiation resistance and ground loss play into all of this?
Maybe you could explain to the readers of this thread why no measureable current flows in a properly designed and constructed RF ground radial system and at the same time radiates?