Par 9 Chap 3 distance is 47,853.6 divided by the frequency in kHz.) Although the FCC is 157,000 divided by the frequency in kHz. Expressed in meters, this shall not exceed 15 microvolts per meter. (Expressed in feet, this distance away from the apparatus a distance equal to the wavelength divided by 2 pi, paragraph 15.7(c)). The total electromagnetic field, produced at any point such equipment shall not exceed certain power limitations (see FCC Part 15, Rules, Part 15, paragraph 15.7). FCC Rules and Regulations require that the Federal Communications Commission (FCC) (47 CFR, Section 15.7; FCC radiation of a signal, it is considered a restricted radiation device by to airports. is particularly appropriate for signal generator operations on or adjacent and using the lowest power necessary. A careful consideration of this matter avoiding local aeronautical frequencies to the maximum extent possible, areas. Even then, users should minimize the duration of radiating tests, the selected bands given in Appendix 2, should be confined to shielded users should take all practical steps to avoid radiation. Radiation, in electromagnetic interference and the accompanying hazard to safety services, (directly or indirectly) by a signal generator. In the interest of avoiding should scrutinize any operation which results in the radiation of a signal the shielding provided by a typical building may be sufficient. Users enclosure. This need not be a copper plated, anechoic chamber. Sometimes, radiation be unavoidable, is to confine this radiation to a shielded them to antennas or other radiating devices. A second method, should that signal generator users can avoid interference is simply not to connect 10. interference. Due to these and other differences, different methods are used to preclude authorization has been obtained from the FCC, a signal generator is not. test station is an authorized transmitter. Unless special temporary navigation land test stations and signal generators. A radionavigation land aeronautical services. Users should note the difference between radio- to insure that their operations do not cause disruption or interference to Part 2, paragraph 2.905). Users should therefore take adequate precautions generator is not an authorized station (47 CFR, Section 2.905; FCC Rules, ference is possible from both modulated and unmodulated signals. A signal watt) can cause interference out to a distance of several miles. Inter- stances, for instance, a signal generator with an output of -30 dBW (1 milli- aeronautical services out to a substantial distance. Under some circum- very low-level radiated signal can cause disruption and interference to ference. Aviation receivers are highly sensitive. Consequently, even a maintenance and other activities can be a source of electronagnetic inter- of the National Airspace Systen. However, the use of signal generators for avionics, and aircraft antennas. Maintenance is essential to the operation variety of purposes including the maintenance of aviation ground systens, 9.
SHIELLING ADEQUACY. If the use of a signal generator results in the TECHNIQUES TO AVOID INTERFERENCE WITH AERONAUTICAL SERVICES. One way GENERATORS• BACKGROUND - SIGNAL CHAPTER 3. SIGNAL GENERATORS 2/13/81 Page 4 Signal generators are used for a AC 170-6C
Page 5 and Development Service Director, Systems Research ROBERT W. WEDAN Research and Development Service at the address given in paragraph 8. information, please contact the Spertrum Management Branch of the Systems REQUESTS FOR INFORMATION ABOUT SIGNAL CANERATORS. For additional nautical bands shown in appendix 2. information to those signal generators that can tune the selected aero- equipment manuals. Manfacturers could limit the distribution of this AC at the time of sale and/or to include its cautionary remarks in their generator manufacturers may wish to provide their customers a copy of this SIGNAL, GENERATOR MANUFACTURERS. 12. at numerous points is recommended. be conducted at this distance from the outside of the enclosure. Testing enclosure itself may be larger than the distance given above, testing should recommended as a test for determining shielding adequacy. Since the adequate shielding is available. This 15 microvolts per meter limitation is microvolts per meter practically precludes such an operating practice unless radiate signal generator test signals, the field strength limitation of 15 Rules and Regulations do not explicitly prohibit the use of antennas to AC 170-6C Par 12 Chap 3 32303 2/13/81
Honolulu, Hawaii 96813 P.O. Box 4009 Federal A Mation A Distret: APC-430.3 Seattle, Washington FAA Building, Boeing Field Federal Aviation Administration Frequency Management Officer, ANW-426 Burlington, Massachusetts 12 New England Executive Park Federal Aviation Administration Frequency Management Officer, ANE-464 Des Plaines, Illinois 60018 2300 East Devon Avenue O'Hare Lake Office Center Federal Aviation Administration Frequency Management Officer, AGL-437 Jamaica, New York 11430 Federal Building JFK International Airport Federal Aviation An officer AA-426 Kansas City, Missouri 64106 Federal Building 001 E. 12th Street Federal Aviation Administration Frequency Management Officer, ACE-432 Anchorage, Alaska 99501 632 Sixth Avenue Federal Aviation Administration Frequency Management Officer, AAL-430B Office 2/13/81 98108 APPENDIX 1. REGIONAL FREQUENCY MANAGEMENT OFFICERS' ADDRESSES 01803 Page 1 Hawaii; Guam; Samoa Idaho; Oregon; Washington Rhode Island; Vermont Massachusetts; New Hampshire; Connecticut; Maine; Ohio; Wisconsin Michigan; Minnescta; Illinois; Indiana; West Virginia Pennsylvania; Virginia; New Jersey; New York; Columbia; Maryland; Delaware; District of Nebraska Iowa; Kansas; Missouri; Alaska Area of Responsibility Appendix 1 AC 170-6C
Page 2 Los Angeles, California 90009 Worldway Postal Center P.O. Box 92007 Federal Aviation Administration Frequency Management Officer, AWE-406 Fort Worth, Texas 76101 P.O. Box 1689 Federal Aviation Administration Frequency Management Officer, ASW-406 Atlanta, Georgia 30344 P.O. Box 20636 Federal Aviation Administration Frequency Management Officer, ASO-434 Aurora, Colorado 80010 10455 East 25th Avenue Federal Aviation Administration Frequency Management Officer, ARM-406 Office (cont) Appendix 1 AC 170-6C islands); NevaJa (including offshore Arizona; California Texas New Mexico; Oklahoma; Arkansas; Louisiana; Carolina; Tennessee North Carolina; South Kentucky; Mississippi; Alabama; Florida; Georgia; Utah; Wyoming North Dakota; South Dakota; Colorado; Montana; Area of Responsibility 2/13/81
24.25-25.25 15.7-16.2 14.4-15.35 9300-9500 9000-9200 8025-8400 7300-7975 7115-7250 5350-5470 5000-5250 2700-2900 1250-1350 960-1215 225-400 118-137 108-119 74.6-75.4 1605-1800 510-535 190-415 2/13/81 GHz GHz GHz MHz MHz MH z MHz Miz Miz MHz MHz MHz MHz MHz Miz MHz kHz kHz kHz
• U. 8. COVERNMENT PRINTDIO OPPICS: 1981 261-122/1072 Page 1 (and 2) Airport Surface Detection Equipment (ASDE II) Airport Surface Detection Equipment (ASDE III) Television Microwave Link (BRITE) Airborne Weather Radar Precision Approach Radar (PAR) Radar Microwave Link (RM) Radar Microwave Link (RML) Radar Microwave Link (RL) Airborne Weather Radar Microwave Landing System (MLS) Airport Surveillance Radar (ASR) Air Route Surveillance Radar (ARSR) Avoidance System (BCAS: 1030/1090 MHz) Beacon (DABS: 1030/1090 MHz), Beacon Collision DME, TACAN, ATCRBS (1030/1090 MHz), Discrete Access (328.6-335.4 Miz) Transmitters (243 MHz), and ILS Glide Slope UHF Air/Ground Communications, Emergency Locator Transmitters (121.5 MHz) VHF Air/Ground Communications and Emergency Locator VOR and ILS Localizer Marker Beacons Aeronautical Radio Beacons Aeronautical Radio Beacons Aeronautical Radio Beacons SELECTED AERONAUTICAL BANDS APPENDIX 2. Apperdix 2 AC. 170-6C