| 摘要 |
PROBLEM TO BE SOLVED: To provide a voice communication terminal device without damaging the sound quality of a voice signal input from a voice communication terminal device and transmitted from a communication terminal, even if the voice communication terminal device and the communication terminal are connected to a common power supply.SOLUTION: The voice communication terminal device includes a first capacitor C1 connected between an input voice signal amplifier 50 and an input voice signal out terminal 22a, and a second capacitor C1 connected between a ground potential portion G10 and a ground potential terminal 22d of the voice communication terminal device 10. Thus, a loop-shaped ground line is intercepted. A noise removal resistor Rn is connected between the input voice signal amplifier 50 and the input voice signal out terminal 22a, in series with the first capacitor C1. By this, noise is removed from a voice signal extracted as a potential difference between the ground potential terminal 22d and the voice signal out terminal 22a, so that the sound quality of the voice signal transmitted from a mobile phone 26 is not damaged. |
