Back تردد متطرف الانخفاض Arabic ELF Catalan Extremely Low Frequency Danish Extremely Low Frequency German Extremely low frequency English Frecuencia extremadamente baja Spanish بسامد بسپایین Persian ELF (taajuusalue) Finnish Extrêmement basse fréquence French अत्यधिक निम्न आवृत्ति (ELF) Hindi
| Radiospectrum | |
|---|---|
| 3 Hz 100.000 km | |
| ELF | |
| 30 Hz 10.000 km | |
| SLF | |
| 300 Hz 1.000 km | |
| ULF | |
| 3 kHz 100 km | |
| VLF | |
| 30 kHz 10 km | |
| LF (LW) | |
| 300 kHz 1 km | |
| MF (MW) | |
| 3 MHz 100 m | |
| HF (SW) | |
| 30 MHz 10 m | |
| VHF | |
| 300 MHz 1 m | |
| UHF | |
| 3 GHz 100 mm | |
| SHF | |
| 30 GHz 10 mm | |
| EHF | |
| 300 GHz 1 mm | |
Met extremely low frequency of ELF worden frequenties in het radiospectrum aangeduid tussen 3 en 30 Hz. De radiogolven hebben een golflengte van 10.000 tot 100.000 kilometer.