| 摘要 |
PURPOSE:To display the telephone number of a opponent station only by fitting an attachment simply to a general telephone set by detecting the telephone number of the opponent station based upon the dial signal sound. CONSTITUTION:An attachment 80, which can be stuck on the surface of the telephone set main body, is equipped with a mike 10 to collect the dial signal sound, a telephone number detecting means 20 to convert the signal sound to the telephone number and a telephone number displaying means 30, and displays the telephone number of the calling opponent to whom the caller dials, by the telephone set number displaying means 30. After the dial signal is sent and the constant time passes, by deciding with a time detecting means 40 that the opponent responds, or executing the manual operation when the opponent responds, a call charge calculation 50 is executed and a call charge displaying 60 is executed based upon the telephone office number by the telephone number detecting means 20. |
