Middle frequency-frequency convertor  中频变频器

audio frequency and video frequency processing  生物燃料电池; 音频和视频处理

Belgium OSB double frequency(work-intermediate frequency) Queching machine  比利时OSB双频(工中频)感应淬火机

correlation in frequency domain and frequency domain  时频相关性

cyclic frequency-spectrum frequency domain  循环频率-谱频率域

deteeting the ground point with low frequency electric current signal changing its frequency  低频信号变频探测

double frequency(low intermediate frequency) Queching machine  共昌双频(低中频)感应淬火机

flashing frequency， critical flicker frequency  临界闪变频率; 停闪频率

FMVFT Frequency Modulated Voice Frequency Telegraph  调频音频电报

Frequency Conversion to Working Frequency  变频转工频

frequency error Frequency  循环频率差

frequency pushing and frequency pulling  频率推挽

frequency-rising and frequency-falling  升降频

FSVFT Frequency Shift Voice Frequency Telegraph  移频音频电报

High frequency and low frequency  高频与低频信息

high-frequency and modulation frequency signal generator  高频调频信号发生器

high-frequency group and low-frequency group equalizer  高低群均衡器

losing lock frequency， unlocked frequency  失锁频率

Low Frequency and Acoustic Frequency  低频与声频