Telephone exchange for wire telephone and radio telephone

Claim 1

A telephone exchange comprising: a wire extension interface having a plurality of first extension ports for wire telephones; a radio extension interface having a plurality of second extension ports for radiotelephones; a main line interface for connecting main lines; channel means for connecting or releasing channels between extensions or between extensions and main lines; extension ports status storage means having a first table for storing dial numbers in association with physical numbers of said first extension ports and said second extension ports and a second table for juxtaposing and registering the physical numbers of said first extension ports in association with the physical numbers of said second extension ports; and control means for performing a control operation in which (a) a talking channel is connected when one of said first extension ports or one of said second extension ports that is juxtaposed and registered in said extension ports status storage means in association with said one of said first extension ports is put in an off-hook state and said talking channel can be maintained even if another one of said first extension ports or of said second extension ports is put in the off-hook state, and (b) when said one of said first extension ports or said one of said second extension ports is put in an on-hook state, said talking channel is transferred to said another one of said first extension ports or of said second extension ports which has been put in the off-hook state, without supplying the one of said dial numbers which is associated with said another one of said first extension ports or said second extension ports.