TELEPHONE EXCHANGER

PURPOSE:To obtain suitable mounting construction to the extension or reduction of a system, by providing buffers for a mother board connecting a printed board mounting subscriber circuits and outgoing registers of a telephone exchanger and a printed board mounting a central processing means. CONSTITUTION:Mother boards 27 and 29 for subscriber circuits and outgoing registers are connected with a board connector 32, and as required, many mother boards are connected with connectors. The mother boards 27 and 29 are connected to a terminal 31, printed boards 21 and 22 are connected with a pattern 25, buffers 26 are provided between the board 27 and the terminal 31 and the printed boards 21 and 22 mounted with the subscriber circuit or outgoing registers are connected to the mother boards with the connectors 23 and 24. The total number of the subscriber circuits and the outgoing registers can be increased or decreased depending on the number of subscribers and the frequency of usage and the printed boards and the mother boards can be removed or added accordingly.