| 摘要 |
<p>With a cover (2) closed so that resistors (R1,R2) are added to a conductor (L1), the resistance between a contact (C1) and the microphone terminal connected to the conductor increases in a stepwise manner when the distance between the speaker (7) and the microphone (10) is increased. With the cover partially opened, the resistance of the slider equals that of resistor (R1) and, with the cover fully open, the resistance of the slider equals the sum of the resistances of the two resistors. An independent claim is included for a telephone handset.</p> |
