U.S. Code of Federal Regulations
Regulations most recently checked for updates: Aug 28, 2025
(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.
