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Generally the Spirit of the Part 15 law seems to be not to cause interference to a licensed station. We here at RangeMaster follow FCC law. Of course you should follow FCC law and fully cooperate with the FCC. Here is subpart 15.219:
”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 heaterpower) shall not exceed 100 milliwatts.
(b) The total length of the transmission line, antenna and ground lead (if used) shall not exceed 3meters.
(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.”
See the Ground hints page for an discussion of grounding.
See the Ground rules page for an discussion of grounding rules including what the FCC may look for in a compliant ground.
A legal issue that comes up is the “What is the ground lead” issue. The part 15.219 (b) antenna 3 meter limit states “The total length of the transmission line, antenna and ground lead (if used) shall not exceed 3 meters.” We can't interpret FCC law, only the the FCC can do that. An important thing to remember with the AM1000 unit is that the unit needs to be properly grounded for the lightning protection circuitry to function properly. We recommend a good ground from the transmitter box to a suitable ground for
lightning protection. See the
Ground hints page for more information.
Another legal issue is station identification. Here is the rule on that issue : (Title47 Sec. 73.3550) Users of non licensed, low-power devices operating under part 15 of this chapter may use whatever identification is currently desired, so long as propriety is observed and no confusion results with a station for which the FCC issues a license.
One other area to be careful of is playing copyrighted music.
Operating on 1710, the transmitter is certified to operate on 1710 so you can use 1710, but the rules are different for that frequency. Instead of rule 15.219 you would be operating under rule 15.223 which is more restrictive:
Section 15.223 Operation in the band 1.705 - 10 MHz.
(a) The field strength of any emission within the band 1.705-10.0 MHz shall not exceed 100microvolts/meter at a distance of 30 meters. However, if the bandwidth of the emission is less than 10%of the center frequency, the field strength shall not exceed 15 microvolts/meter or (the bandwidth of the device in kHz) divided by (the center frequency of the device in MHz) microvolts/meter at a distance of30 meters, whichever is the higher level. For the purposes of this Section, bandwidth is determined at the points 6 dB down from the modulated carrier. The emission limits in this paragraph are based on measurement instrumentation employing an average detector. The provisions in Section 15.35(b) for limiting peak emissions apply.
(b) The field strength of emissions outside of the band 1.705-10.0 MHz shall not exceed the general radiated emission limits in Section 15.209
The AM1000 unit has been certified by the FCC and is legal to use as long as it is
installed properly. The FCC agent is the final authority though. However there are questions that come up on a regular basis.
The 500 foot /(a few blocks) , range limit statement.
Another legal question that comes up is the kit issue. Here is how Part 15 defines a kit in Sec 15.3(p)
"Kit. Any number of electronic parts, usually provided with a schematic diagram or printed circuit board, which, when assembled in accordance with instructions, results in a device subject to the regulations in this Part, even if additional parts of any type are required to complete assembly"
Here is Section 15.23(a)
"Equipment authorization is not required for devices that are not marketed, are not constructed from a kit, and are built in quantities of five or less for personal use."
Equipment authorization means certification.
Often kits or antennas will use the term "Part 15 compliant". Be very cautious here. When someone calls their product that there is no one regulating them and they have no apparent responsibility to live up to that claim. If you operate a "Part 15 compliant" product and it causes interference to an ambulance service for example, then YOU are responsible, not the person or company that claimed the compliance.
Section 15.203 generally prohibits using any antenna except the antenna certified with the transmitter
Be cautious with companies that sell a certified transmitter and (Oh, by the way) sell an accessory antenna that appears to violate FCC rules.
Section 15.204 prohibits selling amplifiers intended for Part 15 devices.
A typical encounter with the FCC would entail just a phone call from them asking for your certification number. Most of the time (as long as you are using a certified transmitter) they won’t even come by to inspect your installation. You don’t want to be using an uncertified transmitter (especially a kit) if you get a call from the FCC. It is a good idea to broadcast your contact information at least hourly so that in case the FCC wants to contact you they can easily. Also you can leave a package at the transmitter site where it can easily be seen containing the certification information, in case the FCC should visit when no one is present.
When you go on the air with a part 15 do not contact the FCC to let them know of your operation, they don’t want you to. They have no way to deal with the information. They will find you if they need to. We have had many contacts through the years with the FCC, if you get a visit just be honest and open, I have found they are easy to get along with and pleasant unless they feel that you are trying to pull some sort of trick on them. Like we said before most of the time a site visit shouldn’t be necessary, but if it is be open and honest, if there is problem honestly present your side. If they want you to change something to bring you into compliance they will give you a paper describing what needs to be done and then return in 30 – 60 days to check to see if the change has been done. We have never heard of one of our transmitters being shut down because of improper installation, the agent has always given the customer time to fix any issue and has allowed them to continue to operate.
Please be aware that even if your equipment is properly installed and passes an FCC inspection, you might still be the subject of a complaint from a nearby broadcast station or member of the general public. Inappropriate or frivolous complaints are filed with the FCC regularly.
The FCC is an independent governmental agency, answerable only to congress, we cannot guarantee and/or we cannot be held responsible for what the FCC may do or decide in any particular situation.