busy signal
短語詞組
- busy back signal 忙回信號;占線信號
- busy flash signal 占線信號;占線閃光信號
- busy tone signal 占線信號;忙音信號
- subscriber -busy signal 用戶忙信號;用戶占線信號
- busy -flash signal 占線閃光信號
- busy signal system 明顯損失制
- busy signal generator 忙音發(fā)生器
- group busy signal 群占線信號
- audible busy signal 音響占線信號;可聞忙音訊號;忙音信號 返回 busy signal