Telephone music-on-hold device
作者： Robin K. L. Tang , Donald C. L. Tang
DOI:
关键词: Telephone exchange 、 Dual-tone multi-frequency signaling 、 Handset 、 Telephone switchboard 、 Two-wire circuit 、 Electrical engineering 、 Telephone line 、 Computer science 、 Class 4 telephone switch 、 Class 5 telephone switch 、 Telecommunications
摘要: A telephone music device adapted to be inserted within the hollow portion of a handset. The draws power directly from line and requires no external supply. When handset is in upright position, as normally utilized for conversation, electrically disconnected circuit. However, when laid down such on table, becomes interconnected with It therefrom generates musical melody which coupled line. Alternate embodiments can clipped or base modular telephone.
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