| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a communication apparatus for reducing a possible rapid change of current and voltage in a communication line when an externally installed telephone capable of transmitting a selective signal in a relatively short period from off-hook is connected to the communication line, and a method of controlling the communication apparatus. <P>SOLUTION: When an externally installed telephone in a disconnection state with respect to a communication line is connected to the communication line, the communication apparatus sets an SDAA at a lower impedance than that on the telephone side upon detection of off-hook of the telephone, and starts line capture via the SDAA. Thereafter, the communication apparatus connects the telephone to the communication line by switching an H relay before a selective signal transmission from the telephone is started, and terminates the line capture via the SDAA. <P>COPYRIGHT: (C)2012,JPO&INPIT |
