| 摘要 |
PROBLEM TO BE SOLVED: To allow a portable telephone set to make recalling automatically or to inform a user that the telephone set is at the outside of a communication zone in the case that a speech is interrupted because of poor electric field strength of a received radio wave. SOLUTION: The telephone set is provided with a speech interrupt discrimination circuit 9 that discriminates whether the speech is terminated normally or abnormally when the speech is interrupted, a calling/call reception discrimination circuit 10 that discriminates whether the speech is started by calling or call reception before the speech is interrupted, and a memory 13 that stores information including message output data, calling history and call reception history. When it is is discriminated that the speech is terminated abnormally, the electric field level is detected, and when the electric field level is a speech- available level, newest call data are read from the calling history or the call reception history stored in the memory 13 and the telephone set makes recalling automatically to the opposite party whose speech is interrupted. When the electric field level is discriminated to be a speech-disable level, the telephone set output a voice message denoting that the portable telephone set is outside of the communication zone. |
