頻段I的 ELF
頻率範圍：5 - 2 000 Hz
帶寬：-3dB
濾波器衰減：-80 dB/dec 低於5 Hz；-40 db/dec 2 kHz以上
HI-3638低頻率電磁波測試儀頻段II的VLF
頻率範圍：2 - 400 kHz
帶寬：-3dB
濾波器衰減：-80 dB/dec 低於2 kHz；-40 db/dec 400 kHz以上

The ELF of band I
Frequency range: 5 - 2 000 Hz
Bandwidth: -3dB
Filter attenuation: -80 dB / dec less than 5 Hz; -40 db / dec 2 kHz or more
HI-3638 VLF for Low Frequency Electromagnetic Wave Tester Band II
Frequency range: 2 - 400 kHz
Bandwidth: -3dB
Filter attenuation: -80 dB / dec below 2 kHz; -40 db / dec 400 kHz or more