carrier telephone repeater
载波电话增音机
基频带增音基
载波电话中继器
基频带中继器
high frequency telephone
multichannel carrier-frequency telephone terminal
negative impedance telephone repeater
single-channel carrier frequency telephone terminal
submerged telephone repeater
Voice-frequency telephone channel
carrier frequency repeater
carrier frequency repeater equipment
high-frequency repeater distribution frame
Middle frequency-frequency convertor
VFREP Voice Frequency REPeater
voice-frequency repeater
video-telephone, viewphone, visual telephone
audio frequency and video frequency processing
Belgium OSB double frequency(work-intermediate frequency) Queching machine