| 摘要 |
PURPOSE:To increase machine interface, by automatically changing the sound volume of callout tone of a telephone set. CONSTITUTION:When an incoming signal enters terminals 1 and 2, the signal is detected at an incoming signal detection section 3. One of these detected outputs 4 is given to a callout tone generating section 5 as it is, and the other enters a callout time (or number of times) detection section 6. When the section 6 receives the output 4 for a sprescribed time (or number of times), a sound volume controlling output 7 is transmitted to the callout tone generating section 5. The section 5 generates a callout tone when it inputs the output 4, and when the output 7 is inputted, the callout tone is increased. |
