47 CFR 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.