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Here is the FCC rule:

Section 15.219 Operation in the band 510 - 1705 kHz.

(a) The total input power to the final radio frequency stage (exclusive of filament or heater power) shall not exceed 100 milliwatts.

(b) The total length of the transmission line, antenna and ground lead (if used) shall not exceed 3 meters.

(c) All emissions below 510 kHz or above 1705 kHz shall be attenuated at least 20 dB below the level of the unmodulated carrier. Determination of compliance with the 20 dB attenuation specification may be based on measurements at the intentional radiator's antenna output terminal unless the intentional radiator uses a permanently attached antenna, in which case compliance shall be demonstrated by measuring the radiated emissions.

The following statement from the FCC DC enforcement office is intended to clear up any confusion about 15.219(b):

The 3-meter combined length specified in Section 15.219(b) refers to the length of all radiating elements. Attaching the ground lead to an unshielded radiating object, or the addition of a ground screen, will cause the effective length of radiating elements to exceed 3 meters, in violation of Section 15.219(b).

 

The idea seems to be that radiating elements have a limit of 3 meters. The total length of the transmission line, antenna and ground lead (if used) shall not exceed 3 meters. The typical definition for "Ground lead" in engineering is, or similar to " A Wire connecting a device to a local ground or GROUND. So following this standard engineering principle the ground lead could be the wire connecting the transmitter ground binding post to the local ground or "Direct Earth Ground".

During the certification process we worked closely with the FCC engineer on how this transmitter was to be installed. We carefully went over how and where the unit was to be installed and grounded, suggested installation configurations, who would be doing the installation, ect.   This information was to be in the manual as a condition of approval. It is very important for lightning protection that the AM1000 unit be properly grounded (safety ground). Also be sure to follow NEC codes for grounding and any local codes. So generally if our installation manual is followed, the RangeMaster should pass an FCC inspection since it was approved based on installation information in the manual. However it is up to any local FCC agent to make a final determination.

Please do not disconnect  a safety ground from any device including ours, no matter what you read on the internet. (Varied claims about grounding, or "certain" heights at which transmitters "have" to be located.

See how the typical indoor AM Part 15 is grounded, there are probably a million of these in use.


We have found with customers that install elevated grounds or ground wires that are obviously intended to radiate most of the time an FCC agent will ask that they be removed. If the transmitter is installed over an existing metal object like a metal roof there usually isn’t a problem.  There is typically no problem with adding radial wires in the dirt ground to improve the electrical connection with the earth. The inspecting agent has the authority to approve or disapprove a particular system. As always follow FCC law and fully cooperate with the FCC.
 

 Keep in mind that for the lightning protection in the transmitter to be effective the DC resistance to ground should be low.

We recommend following FCC law and fully cooperating with the FCC. If you have any issues with an FCC inspection we will help sort things out and work with the inspecting agent to get you into compliance.

To solve a radiating ground system problem you can use shielding or a filter. We offer filters that will limit radiation into the ground. A properly designed shield can be used also, however it is important the the shield be of proper design. A shield that is hot with RF is not a shield.

Please call if you would like to purchase a filter for your system.
See the Ground hints page for information on Ground filters.