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Title 47

Displaying title 47, up to date as of 9/03/2026. Title 47 was last amended 9/03/2026.
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§ 18.309 Frequency range of measurements.

(a) For field strength measurements:

Frequency band in which device operates (MHz) Range of frequency measurements
Lowest frequency Highest frequency
Below 1.705 Lowest frequency generated in the device, but not lower than 9 kHz 30 MHz.
1.705 to 30 Lowest frequency generated in the device, but not lower than 9 kHz 400 MHz.
30 to 500 Lowest frequency generated in the device or 25 MHz, whichever is lower Tenth harmonic or 1,000 MHz, whichever is higher.
500 to 1,000 Lowest frequency generated in the device or 100 MHz, whichever is lower Tenth harmonic.
Above 1,000 ......do Tenth harmonic or highest detectable emission.

(b) For conducted powerline measurements, the frequency range over which the limits are specified will be scanned.

[50 FR 36070, Sept. 5, 1985, as amended at 51 FR 17971, May 16, 1986]