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Federal Communications Commission Record DA 87-1327

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Federal Communications Commission Record DA 87-1327 2 FCC Red Jol. 20 Federal Communications Commission Record DA 87-1327 - With certain exceptions, field strength limits and con- Before the ducted emission limits below 1000 MHz would be Federal Communications Commission specified using a CISPR quasi-peak detector, and emission Washington, D.C. 20554 limits above 1000 MI-h would be specified in peak values - All kits are proposed to be subject to the regulations, including the equipment authorization procedures - Verification of compliance or a grant of equipment NEWS RELEASE authorization would be required for all Part 15 devices except: incidental radiators, home built devices that are Released: October 2, 1987 not marketed (excluding kits), power line carrier systems. subassemblies, and certain exempted digital devices - Labelling would be required for all verified or au- SUMMARY OF PROPOSED CHANGES TO thorized Part 15 devices PART 15 OF THE REGULATIONS - Special accessories that are not readily obtainable from multiple sources and that are needed to enable equipment On September 17, 1987, in Gen. Docket No. 87-389, to comply with the regulations would be required to be FCC 87-300 the Commission adopted a Notice of Pro- included with the equipment when it is marketed (this posed Rule Making to amend Part 15 of its regulations. formerly applied only to computing devices) Due to the extent of the revisions to the regulations proposed in this item, the attached appendices are issued - Devices that are operated with a peripheral(s) to allow manufacturers and consumers to rapidly deter- (external or internal accessories) would be tested for com- mine specific areas of this proposal that may affect them. pliance using the type of peripheral with which the equip- Appendix A contains a brief summary of the proposed ment will be marketed or operated. changes. Appendix B shows the existing transmitter regu- lations and compares those regulations to the proposed Digital Devices: changes, based on the frequency of the transmitter. Ap- - Devices with a power consumption of less than 6 nW, pendix C provides the same comparison for receivers. quartz watches and clocks, modules of quartz watches and Appendix D contains a list of the proposed restricted clocks, musical greeting cards, and battery powered hand- frequency bands and the allocated radio service that is held calculators and electronic games not requiring con- being protected. nection to the AC power lines would no longer be subject to the technical regulations Any questions regarding the proposals in this rule mak- - Portable personal computers with a low power con- ing action should be directed to Mr. John Reed, Room sumption and a low clock rate and their peripherals would 7122, Technical Standards Branch, FCC, Washington, be considered to be calculators D. C. 20554, (202) 653-6288. - The distinction between personal computer peripheral This is an unofficial announcement of the Commission's equipment requiring certification and subassemblies which action. Release of the full text of the Commission's order require no testing for compliance would be defined in the constitutes official action. See MC! .'. FCC, 515 F. 2d 385 regulations (D. C. Circ. 1975). - The permissive change regulations would be clarified - Emission limits above 1000 MHz are proposed to be APPENDIX A applied in the event that digital device clock rates exceed 108 MHz. Summary of Proposed Changes Other Unintentional Radiators: General: - A power line conducted limit of 250 microvolts in the - Marketing regulations for verified equipment and com- frequency range of 450 kHz to 30 MHz is proposed for all puting devices are proposed to be clarified devices except carrier current systems operating in that - All of the equipment authorization procedures would frequency band be contained in Part 2 (currently, some of the certification - Emission limits for receivers would be established procedures are in Part 15) above 1000 MHz - Only one FCC identifier number would be required - The radiated emission limit for CB receivers would be for equipment containing multiple devices relaxed - FCC Form 740 (importation) would no longer be - The emission limit within the frequency range of 30 to required for devices with a power consumption of less 960 MHz is proposed to be tightened to the Class B digital than 6 nW, musical greeting cards, quartz watches and device limits and the limit above 1000 MHz is proposed to clocks, modules of quartz watches and clocks, and battery be 500 uVIm at 3 meters; however, this requirement operated hand-held calculators (including some low clock would be gradually phased-in rate personal computers and peripherals) and electronic games not requiring connection to the AC power lines - Radiated limits for receivers would be measured with the antenna terminals shielded and an antenna conduction - A special temporary authorization or experimental limit is proposed (unless the receiver uses a permanently license would no longer be required for testing devices to attached antenna) determine compliance with the regulations - The technical standards pertaining to measurements to determine compliance would be contained in the regula- tions instead of in the measurement procedure bulletins 6167 FCC 87-300 Federal Communications Commission Record 2 FCC Red Vol. 20 Section 15.249 Operation within the bands 902 - 928 ' The dividing line between the 1000 uV and 3000 uV con- MHz, 2400 - 2483.5 MHz 5725 - 5875 MHz, and 24.0 ducted limits is proposed to be changed from 1.6 MHz to 1.705 6Hz. -24.25 MHz to reflect the projected expansion of the AM broadcasting (a) The field strength of emissions from intentional service. radiators operated within these frequency bands shall com- 12 The proposals contained in the paragraphs concerning the ply with the following: "Detector Functions of Measuring Instruments" as well as the proposed regulations concerning "Measurement procedures" and Fundamental Field Strength Field Strength "Emission limits" will affect these proposed field strength limits. Frequency of Fundamental of Harmonics 13 (mililvoltslmeter) (microvolts/meter) See "Technical Subcommittee (TSC) Review of The Federal Communications Commission's Draft Notice of Proposed Rule 902 - 928 MHz 50 500 Making in the matter of Revision of Parts 2 and 15 of the Rules 2400 - 2483.5 MHz 50 500 Regarding the Operation of Non-Licensed Radio Frequency De- 5725 - 5875 MHz 50 500 24.0 - 24.25 0Hz 250 2500 vices", National Telecommunications and Information Ad minis- tration, U. S. Department of Commerce. November 5, 1986. It (b) Field strength limits are specified at a distance of should be noted that this report recommends lower emission meters. limits in the frequency bands below 960 MHz than the limits proposed in this Notice. A copy of this report will be placed in (c) Emissions radiated outside of the specified frequency the docket file for this proceeding. bands, except for harmonics, shall be attenuated by at 14 least 50 dB below the level of the fundamental or to the Under the current regulations, restricted bands apply to general radiated emission limits in Section 15.209, which- control and security alarm devices operating under the provisions ever is the lesser attenuation. of Sections 15.181-15.187 and 15.201-15.215 of the regulations, 47 CFR 15.181-15.187, 15.201-15.215. As these regulations are the only ones that permit large numbers of consumer devices within FOOTNOTES the frequency bands allocated to the U.S. Government without control as to the exact frequency location, it was necessary to See RM-5l93 on video transmittersin the 902-928 MHz band, restrict the operating frequencies in order to avoid interference to RM-5250 regarding improvement in the AM broadcasting service, certain sensitive Operations. and RM-5575 concerning TV interface devices. See the reference in footnote 13. The NTIA report recom- 2 The limit applied to these early devices was 15 mends lower emission limits in the restricted bands than those microvolts/meter (uV/m) at a distance equivalent to the proposed in this Notice. wavelength of the operating frequency divided by 2 Pi. This limit is currently shown in Section 15.7. Under Sections 302 and 303 of thc Communications Act of 1934, as amended, the Commission is tasked to establish regula- The Commission is tasked under Sections 302 and 303 of the tions necessary to prevent harmful interference to the authorized CommunicationsAct of 1934, as amended, to establish regulations radio services. In order to carry out this obligation, the Commis- necessary to prevent harmful interference to the authorized radio sion has attempted to keep emissions from all Part 15 devices to services. the minimum level practicable or necessary for operation. The Commission has traditionaltyattempted to keep emissions 17 These limits are identical to the field strength limits proposed from all Part 15 devices to the minimum level necessary for for intentional radiators above 30 MHz. We see no justification as operation. Furthermore, the Commission has expressed its desire to why unintentional radiators, primarily receivers, should be to minimize the level of interference received by the authorized allowed to continue to operate at a higher field strength limit radio services. See , for example, "Report on the Status of the than what is proposed for intentional radiators, especially since AM Broadcast Rules". Federal Communications Commission, unintentional radiators tend to be left on, and emitting radio April 3, 1986. frequency signals, for longer periods of time than intentional in most instances, we propose a period of ten years for devices radiators. to come into compliance with the new 5tandards. We believe that 18 CB receivers employing antenna terminals this should provide sufficient time to redesign equipment within See 47 CFR. 15.59. are required to meet a conducted limit at those terminals of 0.2 manufacturers' normal redesign nW. 6 Another category of devices addressed under Part 15 is in- 19 Presently, Subpart C of Part 15 specifies emission limits only cidental radiators.
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