{"data":{"id":"us/47-cfr-18.309","jurisdiction":"us","citation":"47 CFR 18.309","heading":"Frequency range of measurements.","body":"(a) For field strength measurements:\nFrequency band in which device operates (MHz) Range of frequency measurements\nLowest frequency Highest frequency\nBelow 1.705 Lowest frequency generated in the device, but not lower than 9 kHz 30 MHz.\n1.705 to 30 Lowest frequency generated in the device, but not lower than 9 kHz 400 MHz.\n30 to 500 Lowest frequency generated in the device or 25 MHz, whichever is lower Tenth harmonic or 1,000 MHz, whichever is higher.\n500 to 1,000 Lowest frequency generated in the device or 100 MHz, whichever is lower Tenth harmonic.\nAbove 1,000 ......do Tenth harmonic or highest detectable emission.\n(b) For conducted powerline measurements, the frequency range over which the limits are specified will be scanned.","path":["Title 47—Telecommunication","CHAPTER I—FEDERAL COMMUNICATIONS COMMISSION","SUBCHAPTER A—GENERAL","PART 18—INDUSTRIAL, SCIENTIFIC, AND MEDICAL EQUIPMENT","Subpart C—Technical Standards"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-47.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:28Z","sha256":"7522e9f708221cc59d3fc819c101029b46ddd59ae7985290e11e578cb8da0950","source_id":"us-cfr","stale":true,"prev":"us/47-cfr-18.307","next":"us/47-cfr-18.311"},"notice":"GroundRules: Original legal text. Not legal advice."}