# AC 170-6C: Use of Radionavigation Land Test Station and Signal Generators - Type: Advisory circular (guidance, not mandatory unless a rule or AD requires it) - Status: Current - Approved: February 13, 1981 - Last reviewed: November 18, 2002 - Family: AC 170-6 - 14 CFR parts: Unknown Part - Pages: 10 - PDF: https://openairdocs.org/files/sha256/80/5a/805a4a30444523879973572e67058961395512eab5954f461f7c3bf5fa8ea547 - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/91C0C81391CBE8CE86256C750060F3EE.0001 - DRS record last changed: November 18, 2002 - Page: https://openairdocs.org/ac/170-6 ## Versions - [AC 170-6C](https://openairdocs.org/ac/170-6) (Current), approved Feb 13, 1981, 10 pages ## Text Each page's text from the PDF; open the PDF at a page with #page=N. This is OCR from the scanned FAA advisory circular. OCR can misread letters and numbers. ### Page 1 (OCR) considered practical. few techniques for avoiding interference are sufficiently fail-safe to be are used to preclude interference. With signal generators, however, only a means possible. With authorized transmitter stations, a number of techniques It is a basic FAA objective to prevent interference from occurring by every sufficient to depend on correcting interference problems after they occur. air traffic control environment. With a safety service, it is not Administration (FAA) goes to great length to provide an interference-free INTERFERENCE WITH AERONAUTICAL SERVICES. The Federal Aviation 3. CANCELLATION. Advisory Circular 170-68 dated 3/14/78 is canceled. modify those which could interfere with aeronautical services. We hope that users of signal generators will examine their operations and presented by signal generators and how this interference can be alleviated. circular also discusses the potentiai source of electromagnetic interference license these stations within the scope of its regulations. This advisory circular gives information as to the frequencies on which the FCC will Commission's (FCC) Rules and Regulations (47 CFR, Sections 2 and 87). This stations is now incorporated in Parts 2 and 87 of the Federal Communications PURPOSE. Information vital to all users of radionavigation land test CHAPTER I. GENERAL USE OF RADIONAVIGATION LAND TEST STATIONS AND SIGNAL CENERATORS Subject: ADVISORY CIRCULAR Initiated by: ARD-450 Washlagion, D.C. Podoral Aviation Administration DEPARTMENT OF TRANSPORTATION DATE 2/13/81 170-6C ### Page 2 (OCR) Par 4 Chap 2 be 235 pulses per second (pps) +5 pps. - The pulse repetition rate (PRR) for the 1030 MHz AIC beacon test set will 600 uv/m Peak @ 100 feet DME 60 uv/m RMS @ 100 feet Glide Path 20 uv/• RMS @ 100 feet VOR/Localizer Maximum Field Intensity Band attached directly to the generators, are as follows: field limits at a distance of 100 feet using omnidirectional antennas The suggested generator outputs, to produce the specified maximum 87.521(c); FCC Rules, Part 87, paragraph 87.521(c)). testing and nonhazardous to operational facilities (47 CFR, Section The levels listed below have been determined to be adequate for ramp these frequencies will be restricted to a maximum field intensity level. licenses will be issued for operation on other frequencies. Radiation on circumstances, Federal Communications Commission Under certain THAN THE PROTECTED FREQUENCIES. OPERATION OF RADIONAVIGATION LAND TEST STATIONS ON FREQUENCIES OTHER 6 - 1104 MHZ DME (Y Channe1) 1030 MHz Beacon 979.0 MHz 978.0 MHz DME 334.7 Miz Glide Slope 108.1 MHz Localizer 108.05 MHz VOR (Y Channel) 108.0 MHz VOR (X Channel) 75.0 MHz Marker Section 87.521(d); FCC Rules, Part 87, paragraph 87.521(d)). following frequencies with up to 1 watt pover output authorization (4) CFR, licensed by the Federal Communications Commission to operate on the PROTECTED FREQUENCIES. Radionavigation test generators will be to operating facilities. frequencies and power limits which are selected to avoid such interference facilities. Authorized receiver test facilities are assigned specific it may cause errors in aircraft receivers tuned to operating navigational Uncontrolled radiation of such test signals creates a potential hazard since localizer, glide slope, DME, etc., without removing then from the aircraft. signal is sometines useful for checking navigation receivers; í.e., VOR, BACKGROUND - RADIONAVIGATION LAND TEST STATIONS. A radiated test CHAPTER 2. RADIONAVIGATION LAND TEST STATIONS 2/13/81 Page 2 (.01 milliwatts Peak) 23 millivolts Peak 12 millivolts RMS 4 millivolts RMS 50 ohm Generator Output AC 170-6C ### Page 3 (OCR) Page 3 Washington, D.C. 20554 Aviation and Marine Division Safety and Special Radio Service Bureau Federal Communications Commission Washington, D.C. 20590 400 Seventh Street, S.W. Washington, D.C. 20590 Spectrum Management Branch, ARD-450 800 Independence Ave., S.W. Frequency Engineering Branch, AAF-730 Service Systems Research and Development Airway Facilities Service Federal Aviation Administration Federal Aviation Administration and Development Service. should be directed to the Spectrum Management Branch of the Systems Research offices. Questions concerning FAA review of FCC Type Acceptance Applications Facilities Service in Washington or to the regional frequency management should be directed to either the Frequency Engineering Branch of the Airway offices (See Appendix 1). Questions concerning specific assignments following Washington offices or from the FAA regional frequency management Additional information may be obtained from the FAA or the FCC at the REQUESTS FOR INFORMATION ABOUT RADIONAVIGATION LAND TEST STATIONS. paragraph 87.63(a)). The FAA supports this requirement. satisfy requirements (47 CFR, Section 87.63(a); FCC Rules, Part 87, Test Stations be designed and operated with the minimum power necessary to However, FCC Rules require that Radionavigation Land are maximum levels. POWER LIMITATIONS, The power levels indicated in paragrapha 5 and 6 AC 170-6C Chap, 2 2/13/81 ### Page 4 (OCR) 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 (OCR) 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 ### Page 7 (OCR) 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 8 (OCR) 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 ### Page 9 (OCR) 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 --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.