single line switching system 中文意思是什麼
single line switching system
解釋
單線轉換制-
The test methods for the technical specifications of inband pulsing single frequency line signalling system for automatic telephone switching network
電話自動交換網帶內單頻脈沖線路信號技術指標測試方法 -
Inband pulsing single frequency line signaling system for telephone automatic switching network
電話自動交換網帶內單頻脈沖線路信號方式
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