| 摘要 |
PURPOSE:To dispense with a sound echo canceler so as to simplify and miniaturize constitution of the circuit, make hard to receive the influence of surrounding noise, and make the content of talking over telephone hardly to be heard by a fellow passenger so as to keep the talking a secret. CONSTITUTION:Speakers 20R, 20L as receivers for hand-free are provided in the condition which they are received in the head rest 31 of a seat 30, and the directivity of the speakers 20R, 20L is set in the direction of the ears of a seated person. |
